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Friends:

I've been pretty much a factory cartridge kinda guy for the last 50 plus years. In truth, I have been fairly easily satisfied with something from Wally world, especially if its on clearance (not too long ago, right?!!!) for most of my uses in standard rifles - with barrels from 22-26 inches. All good.

But times they are a changing, and I can see reloading as a realistic option, even if supplies are pretty durn lean.

My question is this: are there powders that burn more thoroughly in a short barrel than a long one? For example, A couple years ago I had JES rebore a .243W to .358 Winchester, and slice the barrel down to 18 1/2 inches. Absolutely love it. My nickname for it is "Steady Eddy" - big bullet moving about 23-2400FPS. Devastating..and checks the humane (DRT) box for me. But the factory Hornady's I bought are prolly designed for a 22" - 24" barrel.

But I have other rifles with short barrels as well. If we are going "custom made" by reloading, can we eliminate belchfire situations where powder is still being burned several feet out from the muzzle when a round is touched off, simply by going to a faster burning powder.

Years ago I read JOC observe that a certain load of IMR 4064 in .30-06 in a 165 grainer produces "no great muzzle flash" and a "farly light report". My thinking is, why not pursue this for short barreled rifles, by modulating the powder type?

And no, I'm not limp wristed about recoil etc, and use full throated factory rounds in medium and large caliber magnum rounds, without concern. Bottom line: the self-made loads dont have to be reduced. That said I'm also not all about wringing the last few FPS out of anything, and think Shaman with his 95% rule of max, is probably highly prescient. Think steady eddy. JB would probably call me a "medium medium" kinda guy.

Which powders to consider? Does caliber really matter? If yes, lets throw out the hypotheticals of .270, 30-06, .338WM and .375 (Ruger or H&H).

Gentlemen: Popcorn, anyone? Fire away!







I like my 16inch barrel 30/06 to flash so I use AR2209 (IMR4350 equivalent) - adds visual to the sound effects.
This interests me as well. I know the 300 blackout was designed for short barrel use, with the optimum barrel length being around 9 inches iirc. I also know some powders produce less flash in certain loads. Not an area pf expertise here, and interested in more knowledge on it.
TTT
I am interested in this as well. I've been shooting reloads only in some of my rifles for 30 years; 30-378 Weatherby, 338-378 Weatherby, 300 Baer, and lately a 338 Lapua Magnum. I shoot factory loads only in 308 Win and 223 & any handgun cartridges. I have a couple of SBRs in 223 that are obnoxiously loud and blinding in low light so I am considering handloading 223 for those.
Isn't this getting towards the realm of reduced loads? ie faster powders (with lighter loads) possibally heading towards fillers? The bare minimum powder charge (by weight) I think would be with Trailboss.
I'm not looking for reduced loads. I want to see if a little faster burning powder would increase the velocity lost from a radically shorter barrel...without being SO much faster that it turns the chamber into a hand grenade.
Originally Posted by Magnumdood
I'm not looking for reduced loads. I want to see if a little faster burning powder would increase the velocity lost from a radically shorter barrel...


This
Barrel length does not affect powder choice. The cartridge and bullet affect powder choice
Originally Posted by Blu_Cs
Originally Posted by Magnumdood
I'm not looking for reduced loads. I want to see if a little faster burning powder would increase the velocity lost from a radically shorter barrel...


This


No it will not

Shorter barrel=lower velocity. There ain't no way around it.
The issue is not lower velocity, its muzzle blast. The question is what powders to consider.
Well, maybe SSC powders are a natural fit for short barrels.
Originally Posted by Blu_Cs
The issue is not lower velocity, its muzzle blast. The question is what powders to consider.



I think the volume of the gas the exits the muzzle after the barrel is pretty much going to determine the noise level, and the volume of the powder (as determined by weight of charge) will pretty much determine the amount of gas---and therefore the noise level. I'd try lesser charges of faster burning powders to reduce muzzle blast.
Originally Posted by jwp475
Originally Posted by Blu_Cs
Originally Posted by Magnumdood
I'm not looking for reduced loads. I want to see if a little faster burning powder would increase the velocity lost from a radically shorter barrel...


This


No it will not


Blu Cs;
Good evening to you sir and hopefully it's still early enough that I'm able to get away with a Happy New Year as well.

As has been already posted, that hasn't been our experience - that is we'll load whatever powder gives peak performance in that cartridge and bullet combination and not pay too, too much attention to burn rate.

Perhaps a few quick examples are okay and I'll start with a 788 carbine in .308 which has an 18½" barrel. With bullet weight from 125gr to 165gr powders in the WW748, IMR 4064 burn rate gave better results for accuracy and velocity than say IMR3031.

In a 21" .30-06, again the best results for accuracy and speed with either WW760 or IMR4350 - better for sure than IMR3031, 4064 or H4895.

Lastly in a 20" 6.5x55 and a 21" 6.5x55, we've seen best results with RL19, VV560, IMR or H4831 have yielded best results.

Hopefully that was useful for you or someone out there tonight. All the very best to all in 2021.

Dwayne
It's been my (limited) experience that the powder that gives the highest velocity in a 22-24" length barrel will generally be the same powder that gives the highest velocity in a shorter 16-18" barrel.
It's my understanding that essentially all the powder that's going to burn will be burned within the first few inches in front of the chamber.
As the powder is burned it is converted to a gas. This gas then burns and expands until the available oxygen inside the barrel is consumed.
The fireball at the muzzle is the result of powder gasses reigniting as they come in contact with the atmosphere (oxygen), not powder continuing to burn and after exiting the barrel.
There may be a few granules of powder that didn't burn in the barrel but they're generally not a significant contributor to the fireball.
I think it might be limited territory - less powder means less blast but faster powder means earlier pressure peak and I think the pressure will limit any attempt to try and regain lost velocity from a shorter barrel.

A modulated burn rate powder doesn't exist yet.
Originally Posted by MickeyD
It's been my (limited) experience that the powder that gives the highest velocity in a 22-24" length barrel will generally be the same powder that gives the highest velocity in a shorter 16-18" barrel.
It's my understanding that essentially all the powder that's going to burn will be burned within the first few inches in front of the chamber.
As the powder is burned it is converted to a gas. This gas then burns and expands until the available oxygen inside the barrel is consumed.
The fireball at the muzzle is the result of powder gasses reigniting as they come in contact with the atmosphere (oxygen), not powder continuing to burn and after exiting the barrel.
There may be a few granules of powder that didn't burn in the barrel but they're generally not a significant contributor to the fireball.



Exactly
Please folks. For the purpose of this thread my interest is not best velocity or performance, or optimum anything, it is muzzle blast.

If, for example, that means a .270 W bullet is launched at a lower speed than normal....well OK (so long as it will humanely dispatch a deer).

If you are a reloader who has something to offer in that department, on a firsthand basis, I'm all ears.

Thanks in advance
Blu Cs;
Sorry I misunderstood the question then sir.

For me it'd be either IMR or H4895 that gave the best results with less than top end loads.

That's where I'd start if less blast was the goal.

Hope that helped and good luck.

Dwayne
Dwayne:

I have to say your responses to all questions posed on the fire are generally so well put that it matters little what the original question was.

That said, I thank you for this one which seems absolutely on point to my original question.

Do you have any insight on 4064 or other slightly faster burning powders than the 4895's?

Warm regards from Atlanta, as I sit before a flickering hearth (red oak and hickory mix) with dog at my feet, and I trust you and yours are staying warm and content in your corner of the world.


From folks who should know

https://www.hodgdonreloading.com/re...eled-rifle-require-different-reload-data

DOES MY SHORTER BARRELED RIFLE REQUIRE DIFFERENT RELOAD DATA?
We often get this question. In asking, the customer is unsure if the different barrel length will necessitate a loading data change in the powder chosen. Let’s preface the answer with a quick guide on testing data.

All our data is tested for Pressure and Velocity with instrumented equipment as established by the Sporting Arms and Ammunition Manufacturers Institute (SAAMI). The dimensions of the test equipment are established by SAAMI, both internal (such as chamber) and external such as barrel length. The barrel length is set based upon most popular usage. Rifle calibers are set at 24 inch barrels. Handgun calibers are set based upon the most common use at the time, i.e. a 45 Auto barrel is based upon the barrel length of a 1911, and a 38 Special barrel based upon a standard police issue revolver.

The first thing to remember is that the chamber dimension does not change based upon application. A 223 Remington chamber is the same whether the gun it is in is a handgun or a rifle. The chamber dimension determines the pressure. So, the pressure is the same when fired in that chamber in a rifle or a handgun. The barrel length has no impact on the chamber pressure and hence the reloading data (powder charge and pressure).

The length of the barrel will change the actual velocity you observe. In general as the barrel gets shorter than standard the velocity will lower, and as the barrel gets longer than standard the velocity will increase. This does not change the reload data (powder charge and pressure), just the velocity.

Please note that there is no magic number for how much velocity is lost or gained by changing barrel length. This is because cartridges go from big to small and use varying amounts of different burn speed propellants. The only way to know for sure what the effect is with your different barrel length is to shoot over a chronograph.

So, the quick answer to the question is that the different barrel length will not change the reload data but it will impact the velocity you get.
Originally Posted by windridge
From folks who should know

https://www.hodgdonreloading.com/re...eled-rifle-require-different-reload-data

DOES MY SHORTER BARRELED RIFLE REQUIRE DIFFERENT RELOAD DATA?
We often get this question. In asking, the customer is unsure if the different barrel length will necessitate a loading data change in the powder chosen. Let’s preface the answer with a quick guide on testing data.

All our data is tested for Pressure and Velocity with instrumented equipment as established by the Sporting Arms and Ammunition Manufacturers Institute (SAAMI). The dimensions of the test equipment are established by SAAMI, both internal (such as chamber) and external such as barrel length. The barrel length is set based upon most popular usage. Rifle calibers are set at 24 inch barrels. Handgun calibers are set based upon the most common use at the time, i.e. a 45 Auto barrel is based upon the barrel length of a 1911, and a 38 Special barrel based upon a standard police issue revolver.

The first thing to remember is that the chamber dimension does not change based upon application. A 223 Remington chamber is the same whether the gun it is in is a handgun or a rifle. The chamber dimension determines the pressure. So, the pressure is the same when fired in that chamber in a rifle or a handgun. The barrel length has no impact on the chamber pressure and hence the reloading data (powder charge and pressure).

The length of the barrel will change the actual velocity you observe. In general as the barrel gets shorter than standard the velocity will lower, and as the barrel gets longer than standard the velocity will increase. This does not change the reload data (powder charge and pressure), just the velocity.

Please note that there is no magic number for how much velocity is lost or gained by changing barrel length. This is because cartridges go from big to small and use varying amounts of different burn speed propellants. The only way to know for sure what the effect is with your different barrel length is to shoot over a chronograph.

So, the quick answer to the question is that the different barrel length will not change the reload data but it will impact the velocity you get.


All wonderful points if the issue is velocity, or chamber pressure, or the price of tea in China, none of which apply. The question asked is about muzzle blast.
Blu Cs;
Thanks for the reply and for the kind words again sir, I do appreciate them.

There is another powder that John Barsness has written about that will work like the H4895 and IMR4895 in that it's not upset burning at less than optimum pressure.

Most of the modern powders seem happiest when burning at peak pressure which will also give the most muzzle blast. The 4895s were okay burning at less than top end pressure so should and do give less blast.

I'll do some research in my library tomorrow and see what I can find and will drop you a line if or when I do.

We've shot IMR 4064 in the .308, the '06 and the 6.5Swede as well as the .30-30, but it was so long ago I can't comment intelligently on the muzzle blast. Though I don't recall it being any less than say IMR 3031.

I have fooled with reduced loads in a couple cartridges with the 4895s and there was less recoil and blast with them for sure. Interestingly, one was the .308 Norma Mag with 165gr bullets and it made a really nice shooting '06 with it.

Again, I'll take a look as there are more, I'm just not remembering where I put that bit of information right now. Sorry.

Dwayne

edit to add;
https://hodgdon.com/wp-content/uploads/2016/11/h4895-reduced-rifle-loads.pdf

Sorry. I, too, misunderstood your question.
Really can't offer anything.
Originally Posted by Blu_Cs
Friends:

I've been pretty much a factory cartridge kinda guy for the last 50 plus years. In truth, I have been fairly easily satisfied with something from Wally world, especially if its on clearance (not too long ago, right?!!!) for most of my uses in standard rifles - with barrels from 22-26 inches. All good.

But times they are a changing, and I can see reloading as a realistic option, even if supplies are pretty durn lean.

My question is this: are there powders that burn more thoroughly in a short barrel than a long one? For example, A couple years ago I had JES rebore a .243W to .358 Winchester, and slice the barrel down to 18 1/2 inches. Absolutely love it. My nickname for it is "Steady Eddy" - big bullet moving about 23-2400FPS. Devastating..and checks the humane (DRT) box for me. But the factory Hornady's I bought are prolly designed for a 22" - 24" barrel.

But I have other rifles with short barrels as well. If we are going "custom made" by reloading, can we eliminate belchfire situations where powder is still being burned several feet out from the muzzle when a round is touched off, simply by going to a faster burning powder.

Years ago I read JOC observe that a certain load of IMR 4064 in .30-06 in a 165 grainer produces "no great muzzle flash" and a "farly light report". My thinking is, why not pursue this for short barreled rifles, by modulating the powder type?

And no, I'm not limp wristed about recoil etc, and use full throated factory rounds in medium and large caliber magnum rounds, without concern. Bottom line: the self-made loads dont have to be reduced. That said I'm also not all about wringing the last few FPS out of anything, and think Shaman with his 95% rule of max, is probably highly prescient. Think steady eddy. JB would probably call me a "medium medium" kinda guy.

Which powders to consider? Does caliber really matter? If yes, lets throw out the hypotheticals of .270, 30-06, .338WM and .375 (Ruger or H&H).

Gentlemen: Popcorn, anyone? Fire away!

........................Regardless of cartridge, you load the same way for a shorter barrel as you would for the longer 22", 23" , 24" or 26" barrels. Book listings of slower burning powders that show higher velocities from longer tubes (as an example RL17 in a 300 WSM) also will give higher velocities from the shorter tubes as well. Where velocities are concerned on average, figure about a 15-20 up to maybe a 25-30 fps decrease for every inch of shorter barrel length. In other words from my chrony experience using 2 other buds 300 WSM rifles a few years back and hundreds of rounds for the experiment, my shorty 300 WSM chrony 'd 95.5% the velocities of the longer 24" barreIed 300 WSMs using the same identical handloads. A 4.5% average velocity loss. I own a shorty 16.5" tubed 300 WSM Ruger Frontier (nicknamed MIGHTY MOUSE) which ballistically is a 24-26" barreled 30-06.......As far as which powders burn more efficiently from the shorter tubes? I say do not worry about that at all. Instead, your concern and focus should be what powders offer the best accuracy without sacrificing much if any in the velocity dept from the shorter barrel.....At the range firing max loadings from my Frontier, I notice no noticeable muzzle flash during day light hours. Instead, there is NOISE, a very loud report which of course is muffled with excellent hearing protection. I also own a 375 Ruger Alaskan with a 20" barrel. Aside from powder differences, I do nothing different with my 375 Ruger than with my 300 WSM. The same principles apply......Look in your reloading books and choose your powders accordingly based on what you wish to do based on the velocities you are looking for and just let the noise, burn efficiency and any potential muzzle flash fall by the wayside. If you wish for the lower velocities then use the faster burning powders.
Originally Posted by jwp475
Originally Posted by Blu_Cs
Originally Posted by Magnumdood
I'm not looking for reduced loads. I want to see if a little faster burning powder would increase the velocity lost from a radically shorter barrel...


This


No it will not



Not always true. Depends on how much barrel you are lopping off.
Originally Posted by antelope_sniper
Originally Posted by jwp475
Originally Posted by Blu_Cs
Originally Posted by Magnumdood
I'm not looking for reduced loads. I want to see if a little faster burning powder would increase the velocity lost from a radically shorter barrel...


This


No it will not



Not always true. Depends on how much barrel you are lopping off.


Are you sure about that? That would imply that in some cases a longer barrel may actually be slowing a bullet down. Doesn't sound right.
Reading comprehension isn’t real strong here, most are answering a question that wasn’t even asked
A smaller charge of a faster powder is much less blasty, especially in shorter barrels
H4895 is where I would want to be considering your parameters
Originally Posted by Castle_Rock
Reading comprehension isn’t real strong here, most are answering a question that wasn’t even asked
A smaller charge of a faster powder is much less blasty, especially in shorter barrels
H4895 is where I would want to be considering your parameters


Nice and pithy! Thanks CR!
H4895 will be the powder of choice for cartridges with a bore ratio similar to 7.62 NATO and 30-06. It has been tested by the best. There is a hint in there.

W748, W760 and other ball powders with similar burn rates.


Another hint. Gas ports are about mid barrel length in military arms.


Mid to heavy bullets within the particular cartridge would help also.


Bore ratio of the .243 Winchester ? You might have to live with what you got.










Originally Posted by jwp475
Originally Posted by Blu_Cs
Originally Posted by Magnumdood
I'm not looking for reduced loads. I want to see if a little faster burning powder would increase the velocity lost from a radically shorter barrel...


This


No it will not


Correct, the powder that produces the highest velocity in a longer barrel will also produce the highest velocity in a shorter barrel.
Originally Posted by MickeyD
It's been my (limited) experience that the powder that gives the highest velocity in a 22-24" length barrel will generally be the same powder that gives the highest velocity in a shorter 16-18" barrel.
It's my understanding that essentially all the powder that's going to burn will be burned within the first few inches in front of the chamber.
As the powder is burned it is converted to a gas. This gas then burns and expands until the available oxygen inside the barrel is consumed.
The fireball at the muzzle is the result of powder gasses reigniting as they come in contact with the atmosphere (oxygen), not powder continuing to burn and after exiting the barrel.
There may be a few granules of powder that didn't burn in the barrel but they're generally not a significant contributor to the fireball.

Perfect, absolutely perfect explanation.
Thanks
To add to MickeyD's absolutely correct explanation, muzzle blast is not related to powder type. It is a function of remaining pressure at the muzzle. Peak pressure is achieved generally within a few inches of the chamber - although burn rate does affect this, it always happens quite soon after the bullet leaves the case mouth.

After that moment of peak pressure, the pressure decreases as the swept volume of the bore increases. An analogy being the volume change as a piston moves down a bore. As long as the pressure is high enough, the bullet will keep accelerating. However, in a long enough barrel, pressure would drop to a level that the bullet would begin to lose velocity and eventually come to a stop due to friction.

Muzzle blast, however, is mostly a function of barrel length. The shorter the barrel, the higher the remaining pressure when the bullet clears the muzzle, and thus the louder the blast. Less time and distance to accelerate is also why velocities are lower from a shorter barrel. But as this is about blast, the bottom line is that shorter means louder.
Originally Posted by Blu_Cs


My question is this: are there powders that burn more thoroughly in a short barrel than a long one?

can we eliminate belchfire situations where powder is still being burned several feet out from the muzzle when a round is touched off, simply by going to a faster burning powder.




The assumption you offered in these two separate questions are the main reason you are not getting the simple answer you seek.

Your first question assumes that Muzzle flash is caused by unburned powder. As MickeyD has so eloquently explained to you, this is simply not true.

Your second question incorrectly assumes the same, that unburned powder is the cause of muzzle flash. You also incorrectly assume that shorter barrels produce more muzzle flas because the powder has less time to burn.

Those here have tried answer your question by first pointing out that your assumption as to the cause of MF are incorrect.
To supply you with a simple explanation as to how to reduce muzzle flash you must first be educated on what causes it, it Ain’t Unburned Powder and it Ain’t the short barrel.

Now if you wish to find out which powders produce less muzzle flash, first forget the barrel length and second lose the myth that it is caused by unburned powder.
Originally Posted by jwp475
Barrel length does not affect powder choice. The cartridge and bullet affect powder choice


Correct.
Originally Posted by RockyRaab
To add to MickeyD's absolutely correct explanation, muzzle blast is not related to powder type. It is a function of remaining pressure at the muzzle. Peak pressure is achieved generally within a few inches of the chamber - although burn rate does affect this, it always happens quite soon after the bullet leaves the case mouth.

After that moment of peak pressure, the pressure decreases as the swept volume of the bore increases. An analogy being the volume change as a piston moves down a bore. As long as the pressure is high enough, the bullet will keep accelerating. However, in a long enough barrel, pressure would drop to a level that the bullet would begin to lose velocity and eventually come to a stop due to friction.

Muzzle blast, however, is mostly a function of barrel length. The shorter the barrel, the higher the remaining pressure when the bullet clears the muzzle, and thus the louder the blast. Less time and distance to accelerate is also why velocities are lower from a shorter barrel. But as this is about blast, the bottom line is that shorter means louder.


Correct.

No free lunch.
Originally Posted by Blu_Cs
The issue is not lower velocity, its muzzle blast. The question is what powders to consider.


Less powder less blast. Someone mentioned it IMR3031 or maybe even H335 or faster yet AA2015. But, chamber pressure may be an issue. You will definitely get less bullet speed but if less blast is your target then less powder.
kwg
I thought I said that. I guess maybe I didn't.
Why the concern with MF, unless one is shooting at night?
Originally Posted by steve4102
Why the concern with MF, unless one is shooting at night?



Not concern is blast. Noise, not flash.
There is some correlation between flash and blast. Flash is caused by flammable but unburned gasses in the cloud that forms after muzzle exit. When those gasses mix with new oxygen in the atmosphere, they can spontaneously ignite in a near-explosive way, producing an additional shock wave. Powders with a flash suppressant help control this.

But the major cause of high muzzle blast is simply the release of high pressure, like popping a cork. At 10,000 psi or more.
Originally Posted by Castle_Rock
Reading comprehension isn’t real strong here, most are answering a question that wasn’t even asked
A smaller charge of a faster powder is much less blasty, especially in shorter barrels
H4895 is where I would want to be considering your parameters

Thanks Castle_Rock. As many of the responses have reminded me, adding an inch or two to an already long barrel will increase my velocity without having to increase the powder charge (338 Lapua, 338-378, 30-378)...28" to 30" to 32" barrel will increase the velocity. I have tested this myself. I'll have to revise my query to how do I reduce muzzle blast in very short barreled 223 rifles such as one I have that is classified as an AR pistol. My AR pistol has a 7.5" barrel. Muzzle blast and the fireball in low light are obnoxious and blinding respectively. I have to agree with those that have observed that the velocity lost can only be recovered by a longer barrel.
In my limited experience with a 300 savage and LVR powder got more velocity than H 4895 . With shorter barrels.

But I never really did a complete expierienent comparing loss of velocity between standard and shorter barrels.
But I don't know 🤷‍♀️ If LVR can be used in your listed calibers.
Originally Posted by Blu_Cs
Originally Posted by Castle_Rock
Reading comprehension isn’t real strong here, most are answering a question that wasn’t even asked
A smaller charge of a faster powder is much less blasty, especially in shorter barrels
H4895 is where I would want to be considering your parameters


Nice and pithy! Thanks CR!


And an excellent recommendation for the circumstances. Stick powders tend to be less "blasty" than ball powders out off short barrels.
Lots of good explanations above - is any of this explicit stuff transferable to anatomy - that is - length of esophagus and resulting belch blast, length of lower intestine and - - -, etc.?

Or, do the ingredients rule? Please don't misunderstand the specificity of the inquiry.
Originally Posted by antelope_sniper
Originally Posted by Blu_Cs
Originally Posted by Castle_Rock
Reading comprehension isn’t real strong here, most are answering a question that wasn’t even asked
A smaller charge of a faster powder is much less blasty, especially in shorter barrels
H4895 is where I would want to be considering your parameters


Nice and pithy! Thanks CR!


And an excellent recommendation for the circumstances. Stick powders tend to be less "blasty" than ball powders out off short barrels.

antelope sniper;
Good morning to you sir, I hope that this first Sunday of the year finds you and yours well.

That's an interesting observation and if I think about it I'd have to agree with it, but that's based on the 4895s mostly, though as mentioned I've burned a fair bit of IMR3031 and IMR4064 and can't recall them being quite as well "mild mannered" for lack of a more scientific term.

There's likely some science in the basic makeup of the powders as well and if you or some educated individual cares to share, I'd be interested in reading it.

All the best to you all in 2021 sir.

Dwayne
Originally Posted by mauserand9mm
Originally Posted by antelope_sniper
Originally Posted by jwp475
Originally Posted by Blu_Cs
Originally Posted by Magnumdood
I'm not looking for reduced loads. I want to see if a little faster burning powder would increase the velocity lost from a radically shorter barrel...


This


No it will not



Not always true. Depends on how much barrel you are lopping off.


Are you sure about that? That would imply that in some cases a longer barrel may actually be slowing a bullet down. Doesn't sound right.


Rocky provided a good explanation of some of the physics, maybe that's because he's a rocket scientist, but let me expand a bit.

Changing the burn rate changes the shape of the pressure curve. If we load two different powders to the same maximum pressure, both curves will have the same maximum amplitude, but changing the burn rate change the shape of the curve. These curves are not nice sin curves, but something like this, with the red line representing pressure and the blue line representing velocity:

[img]https://www.shootersforum.com/threads/pressure-curves.70991/#lg=thread-70991&slide=0[/img]

Looking at the above graph, think of the area under the red line as the amount of work performed against the bullet over a given length of barrel. As we increase the powder burn rate, the area under the curve shifts to the left. In other words, more of the work that adds velocity to the bullet is performed in the front part of the barrel. With a slower burning powder, the height of the pressure curve doesn't tapper off as quickly, and longer barrels are able to take advantage of this relative pressure differential for a longer time than shorter barrels.

Additionally, certain cartridge geometries benefit more from a longer barrel/slower powder dynamic. In general, the more over bore a cartridge, the more additional you will notice the differences in the impact of barrel length in both velocity increase due to added barrel length and changes in optimum powder choice relative to barrel length, but again, these are generalities.

With all that said, we must recognize the practical truth behind the claim that barrel length makes no difference in relative velocity potential of different powders. In the context of hunting length barrels, say 20 to 26" inches in length, this is mostly true. At the theoretical level differences do exist, but for the average reloaded, these will be masked by margin of error inherent in the small sample sizes he chronographs.
Originally Posted by Magnumdood
I'm not looking for reduced loads. I want to see if a little faster burning powder would increase the velocity lost from a radically shorter barrel...without being SO much faster that it turns the chamber into a hand grenade.

It has repeatedly been shown that the same powder which produces maximum velocity in a 26 inch barrel will also produce the highest velocity in a carbine barrel. Albeit with excessive noise and muzzle blast.

As to the OP, I have had good luck using IMR 3031 in a carbine length 30-06 with 165 gr ballistic tips.

H4831 produced higher velocities in rifle and carbine barrel lengths. But IMR 3031 produced better accuracy in the carbine.
'taint the velocity that counts - it's the accuracy. My 17 inch barreled '06 does just fine with factory loads. I have no doubt it also will if I load up some 4350 reloads.

If you can't kill something at say 2250, 2300 ain't gonna help. I have personally never found the need (want yes, maybe) for a chronograph, and I have yet to ever use one.
Originally Posted by Magnumdood
I'm not looking for reduced loads. I want to see if a little faster burning powder would increase the velocity lost from a radically shorter barrel...without being SO much faster that it turns the chamber into a hand grenade.


You can't make a silk purse out of a sow's ear, & the amount that you can compensate for a short barrel with powder is pretty limited.....................

But have at & knock yourself out testing & re-testing if that's your gig.

MM
I think the Lever lotion marketing ploy was improved performance with carbines.

I have been told the flagship bullet the FTX has more bearing surface to increase pressure?

But I totally agree we are talking about a very small difference perhaps.
Originally Posted by BC30cal
Originally Posted by antelope_sniper
Originally Posted by Blu_Cs
Originally Posted by Castle_Rock
Reading comprehension isn’t real strong here, most are answering a question that wasn’t even asked
A smaller charge of a faster powder is much less blasty, especially in shorter barrels
H4895 is where I would want to be considering your parameters


Nice and pithy! Thanks CR!


And an excellent recommendation for the circumstances. Stick powders tend to be less "blasty" than ball powders out off short barrels.

antelope sniper;
Good morning to you sir, I hope that this first Sunday of the year finds you and yours well.

That's an interesting observation and if I think about it I'd have to agree with it, but that's based on the 4895s mostly, though as mentioned I've burned a fair bit of IMR3031 and IMR4064 and can't recall them being quite as well "mild mannered" for lack of a more scientific term.

There's likely some science in the basic makeup of the powders as well and if you or some educated individual cares to share, I'd be interested in reading it.

All the best to you all in 2021 sir.

Dwayne


Good Morning Dwayne. Happy New Years to you as well. I hope your 2021 is more prosperous than 2020.

I based my comments on "blastly" powders primarily on personal experience. My first hunting rifle was a Winchester Model 70a in .270, with a 22" barrel. Since we lived in the country and could shoot right out the back door, I poured a good number of powders through that rifle. The ball powders seemed to produce the most blast, especially as it relates to the size of the fireball. At dusk when I'd tough it off with a load of W760 or W785, all you could see through the scope was fire. They made for great 4th of July loads.

As for the actual chemistry behind this, I'm sure we have some real chemist here who can expand upon my crude understanding of the differences between the stick and double based ball powders. Both contain nitrocellulose, but double based powders also contain nitroglycerin, which tends to make them burn hotter, dirtier, and IMO blastyer.

Although this may be one relevant variable, Quickload has a function where it provides muzzle pressure when the bullet exits, which is a nice scientific measure of blastyness. When we take a look at the data, powder burn rate appears to be the more significant variable, with the faster powders being more mild to the ears in shorter barrels, which matches with your experience with the 4895's being more mild to the ears than the 4064's.

Since the OP referenced the 165gr bullets in a short barreled 30.06 I used that for my QL example.

Colum 8 below is pressure at the muzzle.

Code
Cartridge          : .30-06 Spring.  (SAAMI)
Bullet             : .308, 165, Nosler PART SP 16330
Useable Case Capaci: 61.996 grain H2O = 4.025 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 mm
Barrel Length      : 20.0 inch = 508.0 mm

Predicted Data for Indicated Charges of the Following Powders.
Matching Maximum Pressure: 59000 psi, or 406 MPa
or a maximum loading ratio or filling of 110 %
These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !

56 loads produced a Loading Ratio below user-defined minimum of 70%. These powders have been skipped.
Powder type          Filling/Loading Ratio  Charge    Charge   Vel. Prop.Burnt P max  P muzz  B_Time
                                      %     Grains    Gramm   fps     %       psi     psi    ms
---------------------------------  -----------------------------------------------------------------
Alliant Reloder-26 *C              110.0     67.6     4.38    2920    98.8    58422   13980   0.997  ! Near Maximum !
Alliant Reloder-17 *T               99.5     59.7     3.87    2872    99.9    59000   12568   0.995  ! Near Maximum !
Norma MRP *C                       110.0     65.6     4.25    2864    96.0    57460   13582   1.007  ! Near Maximum !
Alliant Reloder-16 *C *T           104.4     58.1     3.77    2854    99.3    59000   12475   0.992  ! Near Maximum !
IMR 7828 SSC                       110.0     64.6     4.18    2827    92.3    58774   12996   0.994  ! Near Maximum !
Ramshot Hunter                     104.2     61.5     3.99    2824    97.5    59000   12508   1.004  ! Near Maximum !
Hodgdon H414                        98.4     59.5     3.85    2816    96.7    59000   12455   1.007  ! Near Maximum !
Winchester 760                      98.4     59.5     3.85    2816    96.7    59000   12455   1.007  ! Near Maximum !
Norma URP *C                       103.8     58.7     3.80    2814    98.9    59000   12182   1.010  ! Near Maximum !
Accurate 4350                      103.3     59.0     3.82    2813    98.9    59000   12213   1.024  ! Near Maximum !
Vihtavuori N550 *C                 100.7     58.8     3.81    2811    98.7    59000   12286   1.015  ! Near Maximum !
Alliant Reloder-19 *C              108.7     62.1     4.02    2811    94.7    59000   12547   1.000  ! Near Maximum !
Hodgdon CFE223 *C                   93.9     58.5     3.79    2809    99.0    59000   12072   1.007  ! Near Maximum !
Hodgdon LVR                        101.0     57.7     3.74    2806    98.4    59000   12085   1.007  ! Near Maximum !
ADI AR 2209                        107.7     61.2     3.97    2803    94.3    59000   12412   0.995  ! Near Maximum !
IMR 4831                           109.0     59.6     3.86    2798    99.0    59000   11958   1.018  ! Near Maximum !
Ramshot Big Game                    93.7     57.1     3.70    2794    99.6    59000   11689   1.010  ! Near Maximum !
Hodgdon Hybrid 100V                106.7     59.0     3.82    2790    99.8    59000   11380   1.006  ! Near Maximum !
Vihtavuori N560 *C                 110.0     64.2     4.16    2789    90.8    54722   13164   1.031  ! Near Maximum !
IMR 4895                            93.3     53.3     3.45    2788    99.7    59000   11694   1.019  ! Near Maximum !
ADI AR 2213                        110.0     63.5     4.12    2788    91.7    57338   12705   1.005  ! Near Maximum !
Norma 204 *C                       102.9     60.7     3.94    2786    94.3    59000   12175   1.001  ! Near Maximum !
Alliant Reloder-15 *C               94.1     53.8     3.48    2779    99.4    59000   11622   1.019  ! Near Maximum !
Norma 203B *C                       94.5     54.0     3.50    2778    99.6    59000   11559   1.020  ! Near Maximum !
Hodgdon BL-C2                       89.0     55.5     3.60    2775   100.0    59000   11420   1.022  ! Near Maximum !
Winchester 748                      86.5     53.2     3.45    2773   100.0    59000   11054   1.014  ! Near Maximum !
Norma 203 old                       96.1     55.5     3.60    2773    99.9    59000   11438   1.031  ! Near Maximum !
Alliant Reloder-22 *C              110.0     63.5     4.12    2771    93.4    53898   12887   1.040  ! Near Maximum !
Hodgdon H4831 SC *T                109.4     63.2     4.10    2768    91.7    59000   12062   0.999  ! Near Maximum !
Hodgdon H380                        95.4     55.7     3.61    2766    98.5    59000   11661   1.022  ! Near Maximum !
IMR 4320                            96.0     54.0     3.50    2766    99.6    59000   11220   1.004  ! Near Maximum !
Hodgdon H4895                       90.7     51.8     3.36    2764    99.8    59000   11295   1.019  ! Near Maximum !
Ramshot Wild Boar                   89.2     54.5     3.53    2764    99.6    59000   11357   1.015  ! Near Maximum !
ADI AR 2206H                        91.0     52.0     3.37    2761    99.6    59000   11331   1.018  ! Near Maximum !
Winchester Supreme 780             106.8     64.4     4.17    2761    94.3    59000   11840   1.003  ! Near Maximum !
Lovex S070                         102.9     58.2     3.77    2760    96.8    59000   11786   1.024  ! Near Maximum !
Shooters World SW4350              102.9     58.2     3.77    2760    96.8    59000   11786   1.024  ! Near Maximum !
IMR 3031                            93.6     50.0     3.24    2759   100.0    59000   10491   1.020  ! Near Maximum !
Accurate MAGPRO                    110.0     66.8     4.33    2758    88.4    53704   12997   1.044  ! Near Maximum !
Winchester 6,5 StaBall *T*C        101.7     62.5     4.05    2757    99.9    59000   11048   1.003  ! Near Maximum !
Ramshot Magnum                     110.0     68.5     4.44    2756    94.0    55608   12427   1.022  ! Near Maximum !
Hodgdon H4350 *T                   105.5     59.0     3.82    2754    95.8    59000   11637   1.008  ! Near Maximum !
IMR 4350                           103.6     58.9     3.81    2754    96.0    59000   11626   1.008  ! Near Maximum !
Lovex D073.6                        91.0     53.6     3.47    2749   100.0    59000   10750   1.033  ! Near Maximum !
Shooters World Match Rifle          91.0     53.6     3.47    2749   100.0    59000   10750   1.033  ! Near Maximum !
Accurate 2520                       89.0     53.6     3.47    2749   100.0    59000   10750   1.033  ! Near Maximum !
Accurate 4064                       95.8     53.5     3.47    2746   100.0    59000   10741   1.051  ! Near Maximum !
Hodgdon VARGET *T                   96.6     53.4     3.46    2743    99.3    59000   11141   1.009  ! Near Maximum !
ADI AR 2208                         96.3     53.4     3.46    2743    99.3    59000   11141   1.009  ! Near Maximum !
Shooters World Long Rifle          101.5     56.7     3.68    2742    97.9    59000   11441   1.024  ! Near Maximum !
Lovex S065                         101.5     56.7     3.68    2742    97.9    59000   11441   1.024  ! Near Maximum !
Vihtavuori N530 *C                  87.6     50.3     3.26    2741   100.0    59000   10829   1.016  ! Near Maximum !
Lovex S062                          95.0     52.8     3.42    2740   100.0    59000   10886   1.027  ! Near Maximum !
Shooters World Precision            95.0     52.8     3.42    2740   100.0    59000   10886   1.027  ! Near Maximum !
Ramshot TAC *C                      89.1     54.9     3.56    2738    98.1    59000   11313   1.015  ! Near Maximum !
IMR 4064                            97.2     52.5     3.40    2738    99.4    59000   10979   1.014  ! Near Maximum !
IMR 4451 Enduron *C*T               98.7     55.7     3.61    2737    96.5    59000   11407   1.009  ! Near Maximum !
IMR 8208 XBR                        89.5     51.1     3.31    2733   100.0    59000   10725   1.016  ! Near Maximum !
IMR 4007 SSC                        97.0     56.2     3.64    2733    95.9    59000   11452   1.020  ! Near Maximum !
Hodgdon H335                        82.5     51.5     3.33    2730   100.0    59000   10449   1.019  ! Near Maximum !
Norma 201 *C                        92.1     51.5     3.34    2730   100.0    59000   10814   1.030  ! Near Maximum !
Vihtavuori N540 *C                  93.7     54.1     3.51    2728   100.0    59000   10579   1.023  ! Near Maximum !
Norma 202 *C                        91.4     51.4     3.33    2728   100.0    59000   10437   1.024  ! Near Maximum !
Accurate 2200                       89.2     51.7     3.35    2728    98.8    59000   10997   1.012  ! Near Maximum !
IMR 4955 Enduron *C*T              110.0     61.2     3.96    2727    92.0    58289   11649   1.012  ! Near Maximum !
Vihtavuori N150 *C                 103.3     55.7     3.61    2727   100.0    59000   10636   1.023  ! Near Maximum !
Accurate 2495                       90.1     50.4     3.26    2726   100.0    59000   10318   1.057  ! Near Maximum !
Alliant Reloder-23 *C *T           110.0     61.5     3.99    2723    99.0    49953   12226   1.077
ADI AR 2219                         82.1     48.5     3.14    2723   100.0    59000   10148   1.015  ! Near Maximum !
Hodgdon H322                        87.4     48.5     3.14    2723   100.0    59000   10148   1.015  ! Near Maximum !
Ramshot X-Terminator *C             86.9     53.0     3.43    2719    99.5    59000   10793   1.018  ! Near Maximum !
Accurate 2460                       85.1     52.4     3.39    2718   100.0    59000   10486   1.037  ! Near Maximum !
Lovex D073.5                        85.4     52.4     3.39    2718   100.0    59000   10486   1.037  ! Near Maximum !
Accurate 2230                       85.0     52.6     3.41    2716    99.9    59000   10596   1.028  ! Near Maximum !
IMR 4166 Enduron *C*T               97.7     53.5     3.47    2714    96.6    59000   11056   1.012  ! Near Maximum !
Vihtavuori N140 *C                  98.2     53.9     3.49    2713   100.0    59000   10418   1.019  ! Near Maximum !
Alliant AR-Comp *C *T               88.9     49.1     3.18    2711   100.0    59000    9705   1.026  ! Near Maximum !
Lovex D073.4                        84.0     51.5     3.33    2709   100.0    59000   10333   1.032  ! Near Maximum !
Shooters World AR Plus              84.0     51.5     3.33    2709   100.0    59000   10333   1.032  ! Near Maximum !
ADI AR 2210                         83.4     49.2     3.19    2704   100.0    59000   10256   1.016  ! Near Maximum !
Vihtavuori N135 *C                  99.6     51.6     3.34    2703   100.0    59000    9830   1.031  ! Near Maximum !
Lovex S060                          91.4     50.8     3.29    2702    99.6    59000   10485   1.013  ! Near Maximum !
Shooters World Tactical Rifle       83.8     51.0     3.31    2700    99.9    59000   10325   1.018  ! Near Maximum !
Accurate 3100                      110.0     62.9     4.07    2697    96.3    53240   11765   1.075  ! Near Maximum !
Hodgdon Benchmark                   88.6     49.9     3.23    2696   100.0    59000   10197   1.016  ! Near Maximum !
ADI BM2                             81.6     49.7     3.22    2696   100.0    59000   10170   1.016  ! Near Maximum !
Alliant Reloder-12                  87.3     50.9     3.30    2694   100.0    59000    9887   1.020  ! Near Maximum !
ADI AR 2206                         90.7     51.3     3.32    2692    99.8    59000   10323   1.013  ! Near Maximum !
Accurate 2700                       96.9     57.8     3.74    2687    95.7    59000   10789   1.023  ! Near Maximum !
Winchester WXR                     110.0     62.2     4.03    2683    91.6    49046   12473   1.088
Alliant Reloder-10x *C              84.9     45.8     2.97    2676   100.0    59000    9538   1.031  ! Near Maximum !
Hodgdon CFE BLK *C                  81.2     49.2     3.19    2673   100.0    59000    9988   1.017  ! Near Maximum !
Accurate 2015                       87.4     47.8     3.10    2668   100.0    59000    9467   1.037  ! Near Maximum !
Hodgdon H4831 *T                   110.0     61.1     3.96    2657    89.5    52049   11564   1.059  ! Near Maximum !
Accurate 1680                       74.2     44.3     2.87    2654   100.0    59000    9290   1.015  ! Near Maximum !
Norma 200 *C                        81.3     45.5     2.95    2653   100.0    59000    9300   1.045  ! Near Maximum !
Hodgdon H4198                       82.3     44.2     2.86    2651   100.0    59000    9230   1.008  ! Near Maximum !
Vihtavuori N133 *C                  93.1     48.7     3.16    2650   100.0    59000    9182   1.022  ! Near Maximum !
IMR 4198                            84.6     43.4     2.81    2639   100.0    59000    8913   1.013  ! Near Maximum !
IMR 7828                           110.0     61.1     3.96    2636    88.4    47900   12094   1.094
Vihtavuori N165 *C                 110.0     62.2     4.03    2635    93.1    50686   11280   1.078
Shooters World Buffalo Rifle        73.0     39.0     2.53    2635   100.0    59000    9073   1.011  ! Near Maximum !
Accurate 5744                       71.4     39.0     2.53    2635   100.0    59000    9073   1.011  ! Near Maximum !
Lovex D060                          73.0     39.0     2.53    2635   100.0    59000    9073   1.011  ! Near Maximum !
Vihtavuori N130 *C                  87.8     46.9     3.04    2634   100.0    59000    9048   1.028  ! Near Maximum !
ADI AP 2214                        110.0     65.3     4.23    2630    88.4    50034   11888   1.074
Alliant Reloder-7                   80.0     44.2     2.87    2629   100.0    59000    8982   1.030  ! Near Maximum !
Vihtavuori N160 *C                 110.0     60.3     3.91    2627    90.9    52097   11052   1.066  ! Near Maximum !
ADI AR 2207                         80.2     42.8     2.78    2618   100.0    59000    8799   1.033  ! Near Maximum !
Alliant Reloder-25 *C              110.0     62.5     4.05    2613    94.0    44316   12414   1.136
Vihtavuori N565 *C                 110.0     64.6     4.18    2599    87.5    44467   12268   1.147
Hodgdon H4227                       77.0     40.3     2.61    2584   100.0    59000    8357   1.020  ! Near Maximum !
IMR 4227                            76.8     40.1     2.60    2581   100.0    59000    8333   1.016  ! Near Maximum !
Vihtavuori N120 *C                  82.5     43.0     2.79    2572   100.0    59000    8247   1.036  ! Near Maximum !
Vihtavuori N125 *C                  78.1     41.5     2.69    2572   100.0    59000    8255   1.034  ! Near Maximum !
Lovex S053                          77.6     39.8     2.58    2539   100.0    59000    7970   1.033  ! Near Maximum !
Lovex S071                         110.0     59.4     3.85    2520    93.3    43104   11098   1.187
IMR 7977 Enduron *C*T              110.0     62.2     4.03    2520    80.0    51150   10086   1.081  ! Near Maximum !
Norma MRP 2 *C                     110.0     62.9     4.07    2499    85.5    39554   11877   1.205
ADI AR 2205                         73.6     40.0     2.59    2488   100.0    59000    7577   1.028  ! Near Maximum !
Vihtavuori N110 *C                  73.2     35.5     2.30    2462   100.0    59000    7294   1.046  ! Near Maximum !
ADI AR 2217                        110.0     62.2     4.03    2454    83.9    41387   10945   1.176
Hodgdon H1000 *T                   110.0     62.2     4.03    2454    83.9    41387   10945   1.176
Vihtavuori N570 *C                 110.0     66.3     4.30    2449    75.7    38838   11788   1.216
Hodgdon Retumbo                    110.0     63.2     4.10    2368    84.0    35488   11295   1.267
ADI AR 2225                        110.0     63.2     4.10    2368    84.0    35488   11295   1.267
Shooters World BMG                 110.0     67.6     4.38    2364    72.3    41210    9746   1.194
Lovex D100                         110.0     67.6     4.38    2364    72.3    41210    9746   1.194
Alliant Reloder-33 *C              110.0     68.2     4.42    2363    73.6    36317   11183   1.258
Vihtavuori N170 *C                 110.0     62.2     4.03    2319    75.5    36364    9897   1.272
Vihtavuori 24N41 *C                110.0     67.0     4.34    2314    67.7    38424    9769   1.231
Accurate LRT                       110.0     66.8     4.33    2281    65.1    36232    9839   1.265
ADI AR 2218                        110.0     67.0     4.34    2279    66.5    36036   10177   1.265
ADI AP 100                          71.9     28.4     1.84    2270   100.0    59000    5939   1.050  ! Near Maximum !
Norma 217 *C                       110.0     61.9     4.01    2250    79.2    30073   10836   1.360
IMR 8133 Enduron *C*T              110.0     61.5     3.99    2246    76.7    30655   10465   1.349
Hodgdon H870                       110.0     64.9     4.21    2224    71.5    30991   10269   1.346
Alliant HERCO                       71.5     25.6     1.66    2207   100.0    59000    5654   1.076  ! Near Maximum !
Alliant Reloder-50 *C              110.0     68.0     4.41    2139    65.7    27798   10006   1.411
Lovex S035                          70.5     25.1     1.62    2137   100.0    59000    5077   1.078  ! Near Maximum !
Hodgdon 50BMG                      110.0     63.8     4.14    2136    59.2    30969    8732   1.351
Hodgdon US 869                     110.0     67.0     4.34    2127    62.4    30687    8776   1.360
Lovex D013                          72.7     21.7     1.41    2112   100.0    59000    5138   1.085  ! Near Maximum !
Shooters World Sparta 100           72.7     21.7     1.41    2112   100.0    59000    5138   1.085  ! Near Maximum !
Accurate Nitro 100                  72.7     21.7     1.41    2112   100.0    59000    5138   1.085  ! Near Maximum !
Alliant GREEN DOT                   72.5     23.1     1.50    2098   100.0    59000    5011   1.090  ! Near Maximum !
Alliant RED DOT                     77.5     22.0     1.43    2088   100.0    59000    4985   1.077  ! Near Maximum !
Lovex S015                          73.3     23.2     1.50    2085   100.0    59000    4916   1.089  ! Near Maximum !
Accurate Solo 1000                  73.3     23.2     1.50    2085   100.0    59000    4916   1.089  ! Near Maximum !
ADI AS 30                           76.9     22.7     1.47    2066   100.0    59000    4821   1.084  ! Near Maximum !
Norma R1                            81.3     23.5     1.52    2047   100.0    59000    4715   1.086  ! Near Maximum !
Hodgdon Clays                       80.7     22.1     1.43    2041   100.0    59000    4687   1.076  ! Near Maximum !
Accurate 8700                      110.0     65.6     4.25    2030    62.5    27614    8264   1.421
Vihtavuori 20N29 *C                110.0     67.6     4.38    1995    59.3    26041    8220   1.457
Vihtavuori N32C Tin Star            96.0     27.4     1.77    1978   100.0    59000    4204   1.113  ! Near Maximum !
ADI AS 25 BP                       110.0     21.2     1.37    1727   100.0    39589    3373   1.324
IMR TrailBoss                      110.0     21.2     1.37    1727   100.0    39589    3373   1.324



In this case top velocity comes from a highly compressed load of RL26 and produces 14K psi exiting the muzzle. Since it has it's own chemistry, it's probably not the best example, but H4895 is only around 11.3K. But to be fair, H380 simulates at 11.7K psi a the same velocity, or only 3.5% more then it's single base equivalent.

So the short answer to the OP, yes faster burning powders tend to reduce muzzle blast from shorter barrels.
Originally Posted by antelope_sniper
[ .....


So the short answer to the OP, yes faster burning powders tend to reduce muzzle blast from shorter barrels.




Thank you!
Thinking you maybe found an answer here, but keep in mind there are more pieces to the puzzle if you are inclined to dabble. Jacketed bullets generally perform well within their designed velocity envelope. So too do cast or swaged bullets. I hunted for a spell with a .358 Win and it was prone to knocking the stuffing out of deer and pigs, but it was noticeably inferior to my .44 Mag carbine loaded with paper patched lead at a pedestrian 1,600 FPS. It wasn’t as hard on the ears either. In a .30-30 the old Lyman 311041 cast bullet is quite deadly with a MV around 2,000 FPS.
antelope sniper - I do understand the pressure curves but should've qualified my answer. I meant standard length barrels up to say 26 inch or possibly even up to 28 or 29 inches. I haven't attempted the maths but it doesn't sound right that friction would become the dominent force toward the end of the barrel when using a fast powder, to the point where it starts to slow the bullet down. It would eventually happen but I suspect the barrel would be unpractically long.

I say this because I have a couple of example firearms:
A 29inch barrel Mauser 8mm that always exceeds the velocity of standard barrels eg 150gn @ 3000fps.
I also have a 16.5 inch 9mm carbine that exceeds pistol velocities (not always by much though) and it uses a relatively miniscule amount of relatively fast powder, and has a large void behind the projectile to fill the gas with as it travels down the barrel.

Actually there's a website with published data for velocity versus reducing barrel length - some guys progressively chopped barrels and took readings, for several cartridges. I don't think they used any barrels longer than 22 inches, and sometimes there was minimal speed decrease at length decreases but I don't think the speed ever increased, if you know what I mean. I'll have to go back to their website though to check.
Originally Posted by mauserand9mm
antelope sniper - I do understand the pressure curves but should've qualified my answer. I meant standard length barrels up to say 26 inch or possibly even up to 28 or 29 inches. I haven't attempted the maths but it doesn't sound right that friction would become the dominent force toward the end of the barrel when using a fast powder, to the point where it starts to slow the bullet down. It would eventually happen but I suspect the barrel would be unpractically long.

I say this because I have a couple of example firearms:
A 29inch barrel Mauser 8mm that always exceeds the velocity of standard barrels eg 150gn @ 3000fps.
I also have a 16.5 inch 9mm carbine that exceeds pistol velocities (not always by much though) and it uses a relatively miniscule amount of relatively fast powder, and has a large void behind the projectile to fill the gas with as it travels down the barrel.

Actually there's a website with published data for velocity versus reducing barrel length - some guys progressively chopped barrels and took readings, for several cartridges. I don't think they used any barrels longer than 22 inches, and sometimes there was minimal speed decrease at length decreases but I don't think the speed ever increased, if you know what I mean. I'll have to go back to their website though to check.



Go back and re-read the original string to which I responded.

The question was not about absolute velocities across barrel lengths, best velocity across power burn rates and barrel lengths.
Thanks everyone. I believe I have an answer to my OP that I can process...for now! Learn something everyday here on the fire!
Originally Posted by MontanaMan
Originally Posted by Magnumdood
I'm not looking for reduced loads. I want to see if a little faster burning powder would increase the velocity lost from a radically shorter barrel...without being SO much faster that it turns the chamber into a hand grenade.


You can't make a silk purse out of a sow's ear, & the amount that you can compensate for a short barrel with powder is pretty limited.....................

But have at & knock yourself out testing & re-testing if that's your gig.

MM

Perhaps you should read everything I posted before you chide me.
Originally Posted by antelope_sniper
Originally Posted by mauserand9mm
antelope sniper - I do understand the pressure curves but should've qualified my answer. I meant standard length barrels up to say 26 inch or possibly even up to 28 or 29 inches. I haven't attempted the maths but it doesn't sound right that friction would become the dominent force toward the end of the barrel when using a fast powder, to the point where it starts to slow the bullet down. It would eventually happen but I suspect the barrel would be unpractically long.

I say this because I have a couple of example firearms:
A 29inch barrel Mauser 8mm that always exceeds the velocity of standard barrels eg 150gn @ 3000fps.
I also have a 16.5 inch 9mm carbine that exceeds pistol velocities (not always by much though) and it uses a relatively miniscule amount of relatively fast powder, and has a large void behind the projectile to fill the gas with as it travels down the barrel.

Actually there's a website with published data for velocity versus reducing barrel length - some guys progressively chopped barrels and took readings, for several cartridges. I don't think they used any barrels longer than 22 inches, and sometimes there was minimal speed decrease at length decreases but I don't think the speed ever increased, if you know what I mean. I'll have to go back to their website though to check.



Go back and re-read the original string to which I responded.

The question was not about absolute velocities across barrel lengths, best velocity across power burn rates and barrel lengths.


Okay, got it. I would still think, unless the velocities were really close, that the powder giving the highest velocity would also do so in a shorter barrel - extra win if it happens to be the faster powder.
As has been quoted over and over on this forum, and again. In this thread.

The powder which produces the highest velocity with a specified cartridge and bullet with a 26 (or 30) inch barrel will also produce the highest velocity in a 16 inch barrel.

A different, faster powder, might produce nearly as much velocity in a 16 inch barrel, with significantly less barrel pressure at bullet exit. Which can give less noise, recoil, and muzzle blast.
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