I am wondering because Rl-17 has an impregnated retardent and therefore doesn't initially have a pressure spike can we depend on tradition signs of pressure like sticky , stiff bolt openings? I am wondering if part of the reason we are seeing better velocity is because we are just using more powder than we should and because the traditional signs of pressure are not present we think we are OK? In my feeble mind it takes X amount of pressure to push a given bullet to a certain velocity, there is no majic or free lunch. Are we taking more chances than we should thinking we are OK or safe? I don't know the answer to this question but it along with some others, ( mostly about female logic) have been circling around in my brain. I know there are some very gifted analytical minds on this board so I thought I would ask. The questions about female logic I have come to believe are with out answer and I have come to believe are the price of admission to achieve a happy relationship.
Buckfever1

If RL-17 is anything like the powders used in the new Hornady Superformance stuff (which I am sure it is) then their is a bunch of good reading out there for you to figure it out.

All I know is that I've looked the Alliant data over carefully and there isn't any magic 100+ fps gain in any cartridge with RL-17, as so many handloaders have been reporting. And so far Alliant's is the only pressure-tested data out there.

In fact, the only "magic powder" that's recently appeared in powder-company loading data is Hodgdon Hybrid 100V, which does show a very significant gain in velocity with certain cartridge/bullet combinations. Yet we hear a lot more about RL-17....

I'll also comment that the absence of traditional "pressure signs" such as primer appearance, bolt lift, etc. doesn't mean much. With some of today's components and rifles such signs often don't show up until the pressure is at least 70,000 psi or even higher.

There wasn't a lot of published data when I started loading with RL-17. A chronograph told me when my loads were too hot. Absent were sticky bolt lift and flattend primers...but muzzle velocity became very erratic.

I backed off till I had consistant velocities (270 WSM).About the same velocity as factory ammo with better accuracy.

Dan (not a gun writer)

This isn't a very technical response to what can be a great informative thread, but I have loaded with RL-17 ( 1lb worth ) in a few catridges, and saw no real velocity gain at seemingly safe pressure and in my limited use it was not as accurate as other proven loads.
The exception was in a .30'06 target rifle where I saw nearly 100fps over its previous top end load, but again not as accurate. 2745fps with a 210gr Berger in a 24" barreled .30'06 is attractive but didn't shoot all so well at extended range.

If you put enough of it in you will get traditional pressure signs. Trust me!

A lot of the guys that I shoot with are using it to replace H4350 and seemingly getting more velocity than they could get with H4350. It also seems to burn a little cleaner. I am using it in the .300 WSM with 200gr. bullets and the 6X47 Lapua with 108's. Good accuracy and velocity in both.

Lefty C

I got a genuine 50-60 fps gain in my last 300 WSM over H4350 with 180's. Not monumental by any means, but the gain was there.

Today with the 270 Win at the range, I ran 150 Partitions with Alliants top load of 51.5 gr's... this load was about 70 fps behind 58.0 gr's H4831sc. I believe I could go to 52.0 gr's RL17 in my rifle, but velocity will still fall behind 58.0 of H4831 which runs 2,840-ish.

Of course accuracy is more important than 50 fps...

What I wonder is if the delayed powder burn actually moves more pressure down the barrel to thinner barrel walls that are not designed to withstand it. Maybe it does not show up at the bolt but close to the muzzle.

Well, this is anecdotal and the famous example of one, but in a SA 700 and a OAL of 2.95" my 284 hit 3150fps with R 17 and the very long 140-gr TTSX (1.3"). This was a "stable" load with no primer flattening, case sticking, stiff or frozen bolts and was a 150fps over H4350 when I did reach some of these traditional high pressuren signs.

Not intending it to be a 7mm Rem mag I backed down to 3050fps which is plenty for it's anticipated use as I decided that velocity, within the context of historical known performance parameters, was indicating that pressures were much higher than otherwise indicated.

6mmBR.com has a great thread on RL-17. Bob Jensen and German Salazar are some pretty savy riflemen. They used a strain gauge for their results. http://www.6mmbr.com/reloder17.html

Their article inspired me to try RL-17. A 6mm rem, and a 284 Win showed stunning velocity gains with excellent accuracy. There were more modest gains with the slightly larger cases of the 338 RCM, 7 Rem mag and 300 win mag.

I tried Re 17 in my 06 with 180 Partitions yesterday. At 55 grains, I was getting 2826 from my 24" barrel M70. No pressure signs of any kind and decent accuracy. In my 300 SAUM, I broke 3000 with a 180 Partition, again with no pressure signs. I'm still leery and have backed down accordingly to 2800 in my 06, 2950 in the SAUM.

Huh??? Rifle barrels not designed to handle pressure at the muzzle end?? Please elaborate. Especially on how the pressure wouldn't show up at the breech.

Was a bit curious about that myself......

In theory, as the bullet moves down the barrel, the "powder" container increases in volume, which drops pressure due to the Ideal Gas Law.

I do know that the longer pressure curve is why shotgun shells made with "modern smokeless" have the printed warning on the box about shooting them in Damascus twist barrels. And I have an old family heirloom twist-barreled shotgun with a bulge toward the muzzle.

They were made to shoot black powder shells; black powder has a quick pressure spike. So the steel is thick toward the breech and thin toward the muzzle because with black powder, the pressure had subsided by the time the shot traveled down the bore.

Never heard of this with rifles though, and I'm pretty sure that before the bullet exits the muzzle the pressure is the same up and down the bore and the breech/bolt area would not be spared.

It would seem logical that the heavier chamber section of most rifles would be better able to contain a very brief momentary burst of 60,000 psi pressure (or greater) much more easily than could the thinner barrel walls further down the barrel.

My own understanding, however, is that certain powders create a longer maximum pressure peak and which can produce high speeds than do powders which peak more rapidly and for shorter periods of time. (By the same token, a lower maximum pressure load might also produce more speed if it maintained its high pressure for a longer period than a load which had a higher maximum, but very brief period of high pressure.)

The old DuPont/IMR Reloader's pamphlets were informative in this regard. They showed all or most of their rifle powders with many common cartridges. The maximum test pressures were generally very close. Faster powders in the larger cases never produce speeds anywhere near what the slower powders can even when the faster powders were fired in similar (or higher) pressures. The maximum pressure of a load is less important than maintaining a sufficiently high enough pressure over a longer period in order to keep the bullet accelerating.

smokepole,

Actually, modern pressure testing equipment has shown that black powder shotgun loads don't spike significantly quicker than modern smokeless loads. And it's also been proven that GOOD Damascus barrels will handle modern shotshells just fine.

The standard warning about shooting modern shotshells in Damascus barrels came about because there used to be a lot of cheap "twist" barrels on cheap shotguns. These weren't usually all that well maintained, either, and the cheaply made barrels allowed rust to work its way between the pieces of steel.

Thanks for the link, kinda looks as though R-17 was engineered like the powders used in Hornadys super performance ammo.
I used Barnes data for their 80 Gr. TTSX load & was getting 3500 fps out of a 22" kimber with no pressure indicators...Only fired 3 rounds of that load though.

For an interesting read on Damascus barrels and myth-busting, check out Stewart Bell's multi-part series "Finding out for Myself" in Double Gun and Single Shot Journal--basically, Bell took Damascus barrelled guns, some of which would qualify as wall hangers, and ran proof loads through them. Bell secured the guns in a lead-sled and triggered them remotely.

His conclusions? Basically: Myth Busted. The only guns that failed were those that had such serious internal corrosion or split stocks that they simply couldn't hold during recoil. The rest did fine. Bottom line--if you have a mechanically sound (and thoroughly inspected by a competent gunsmith) Damascus barrelled gun and you know how to handload low pressure shells, you ought to be out shooting it

Well, I guess my grandpa couldn't afford a shotgun with a good barrel; his was a knock-off of an English shotgun, made in the US, and he used the hell out of it. Had to replace the #1 firing pin (double-barrel, exposed hammer) with a hand-made pin. And there is a definite bulge in the barrel about 3/4 toward the muzzle.

Nevertheless and mythbusters notwithstanding, this is the reason for the printed warning on shotgun shells.



Yes, I can follow that part of the logic. But it would also seem logical that the pressure exerted at any point in the bullet's path down the barrel would also be exerted back at the breech/bolt and in the casing, so if there were pressure spikes they would show up there. That was my original point.

smokepole,

A bulged shotgun barrel can occur for many reasons. A bulge 3/4 of the way down is usually caused by a stuck wad. There's no way it was caused just by the pressure of a modern load that far down the bore.

Wow, you can discern that from Montana? 60 years after the fact?

Yep...

ETA: Could have been any number of obstructions though...

So, what you guys are saying is, there never has been a Damascus twist barrel (even a cheap one) that was damaged by shooting modern shotguns shells in it?

Let's begin with some basics, which probably should have been stated several posts ago, when you suggested that modern powders might peak in pressure way down the barrel.

Just because many modern powders burn more progessively doesn't mean the peak pressure occurs all that much further down the barrel. The pressure curve is indeed flatter, but the pressure beyond the first quarter of the bore drops rapidly, because of the rapidly increasing volume of the bore.

In a shotgun barrel the peak is still VERY close in front of the chamber, even with the most progessive smokeless powders, and drops off drastically after that. This is why most shotgun barrels that actually blow apart (for whatever reason) do so in the first few inches in front of the chamber.

When a shotgun barrel (or rifle barrel, or handgun barrel) bulges, it's usually further down the bore, due to an obstruction. It is NOT due to the pressur peaking 20" or so down the bore. Even with the most progessive-burning modern rifle powders, such as Reloder 17, that is a physical impossibility.

Certainly some Damascus barrels have been damaged by shooting modern ammunition, especially cheap ones that have defects, either in their manufacture or due to rust. But the same sorts of barrels would also probably be damaged with black-powder ammo.

Back on topic John...When is more published data going to be available for R-17? Looking at Alliants data, it looks kind of anemic compared to Barnes. Do you know when Nosler #7 or Barnes #5 are going to come out?

It has never made sense to me why so many people are personally invested in the "damascus barrels are dangerous" myth. I would think they'd be happy to find out that such barrels, when properly inspected and in good condition, can indeed be shot with low pressure loads made with modern components. Think of how many old guns could be carried afield again--but no, people would rather repeat myths and tell others "no" than find out for themselves and spend time shooting.

Middlefork Miner,

I have no idea when the next Barnes manual is coming out, though would assume it will before Nosler #7. The guys at Nosler say it takes them about seven years to put a manual together (they are shooting the data for the new one even as the present is in production) and #6 came out in 2007.

How does RL17 produce so much added speed? There are two main reasons--unique burn properties and high load density. In its chemical properties, RL17 is like no other powder available in the U.S. market. Made in Switzerland by Nitrochemie, RL17 has a unique burn-rate controlling chemical that penetrates all the way through the kernels. Other common extruded powders have only a surface coating. Reloader 17's unique penetrating burn-rate regulator smooths out the pressure curve, allowing RL17 to maintain high energy for a longer period of time.

German Salazar, using Bob Jensen's Oehler 43 equipped for pressure-testing, confirmed that the pressure curve for Reloder 17 is much "gentler" than that of other powders in the same burn range. After RL17 hits peak pressure, the energy level doesn't drop as rapidly as with other powders. So there is more energy pushing your bullet for a longer time. Since pressure drops off more slowly, you can achieve more velocity for a given peak pressure.

The second reason RL17 offers so much added velocity is load density. This powder packs very tightly compared to other "slow" extruded powders such as H4350 and H4831sc. For chamberings limited by case capacity, RL17 lets you put more powder (by weight) into the case. That means you're less likely to run out of "boiler room" before you reach max pressure.


Kinda makes since.
Haven't been much in the way of development of new powders for the handloader in a number of years.
We know that new powders have been developed for "high end"
rounds that most of us would never use.
"Us",being handloaders.
Its callled progress and modern chemistry.

dave

Perhaps it is difficult to think about fractions of an inch as significant in terms of timing. Many of us would probably understand the pressure curves a whole lot better if they were printed on barrel length printouts.

As ever, your explanations are appreciated.

Well, this is more along the lines of what I was thinking. I have no idea who bulged the barrel, what kind of ammo they were shooting, or whether the barrel was bulged before smokeless powder was even in use. I just tend to stay away from absolute statements.

What I do know is that the shotgun was a cheap knock-off, and used hard by people who could not afford a good gunsmith and may have been less than fastidious in their cleaning routines. The checkering is worn completely off the pistol grip, the #1 firing pin was replaced, and I misspoke--the barrels actually have three different spots that were bulged.

One spot is about 3/4 down the #1 barrel toward the muzzle, and another is about halfway down, on the same barrel. Both are patched.

The biggest bulge is actually only 12 inches from the breech, on the #2 barrel. But you're right, that could have been just a weak spot in the metal and it could have been done with black powder.



Personally, I don't have anything invested in the damascus barrel myth, and I don't believe I've told anyone what they should/shouldn't do with their own firearms. But if you want to come over and fire this one up, bulged barrel patches and all, send me a PM and I'll give you my address. I'm kind of curious about it myself.

I shot my 30-06 classic 24" barrel and compared the IMR4350 with RL 17. Using 165 Barnes TSX and 57gr. of each.

The IMR loads were 2742fps and the RL loads were 2910fps.

(chronographed just 2 shots each)

I tried working up to 55grs. RL 17 and 200gr AB's. 54grs seemed OK but 55grs. ...cratered the primer a bit and the bolt was a little sticky. I didn't chrono that load.

It is clear that there are some cartridge/bullet combos where Reloder 17 performs roughly 100 to well above 100 fps better than any other powder in Alliant's data. Just look through the 2010 online manual in the 6mm Rem, 25-06, or 270 sections. It's definitely not an across-the-board advantage, though.

The odd thing is how many instances one finds of Alliant's published data showing very little advantage for Reloder 17, yet independent strain-gauge data shows rather a huge advantage for 17 without exceeding SAAMI-max pressure for the cartridge being measured. Look on this very site for data from member "logger" to see such an example(s).

It's just odd.

That's been my limited experience. I worked up 100gr loads with my 25-284, using RL17 and H4350, using identical components other than powder. They were tested on the same day, a few minutes apart. Pressure arrived with the H4350 load at 3220fps (faint ejector marks). The RL17 loads went up to 3320fps with no pressure signs at all. I think there may still be a bit of wiggle room in there, but I'm not going much higher.

Someone please tell us what is the advantage of another 100 fps in trajectory. Specifically, cite the bullet drop of the standard load at 300 yards with a 200 yard zero. Then cite the bullet drop of the Re17 load at 300 yards with a 200 yard zero. Thank you.

I think it's important for a discussion such as this one to not get side-tracked by that red herring. The same principle applies to every aspect of choosing a cartridge, a rifle, and a bullet weight. This is not about whether it's worthwhile to choose a 308 rather than a 300 Savage, it's about performance with the cartridge, bullet, and rifle as givens.

While there may be some validity to that question, let me ask another question. If you pulled up to the gas pump and had the options of "Gas A" and "Gas B" for the same price, but "Gas B" gave 3-4% better fuel mileage with no negative side effects, why would you not give it a try? RL17 is on my powder dealer's shelf, right next to all of the other stuff, so I'm taking my extra 100fps to the house.

For a guy who is running a medium velocity, high BC bullet at longer ranges, 100fps can make a difference. Taking a 200gr .308 Gameking BT at 2600fps versus 2700fps and zeroing both for at max point blank with a 6" vital zone, the 2700fps load yields 1MOA less drop at 500yds. Not a big deal, but not worth totally discounting either.

Who has tried RL-17 with 110-115gr pills in the 257 Roberts? Did it show any gains? Or is Hybrid 100V the best bet?

................Good analogy using the gas pumps.

Modern powder technology allows RL17 to do what it does. Under most if not all hunting situations, will using RL17 mean higher percentages of kill rates in the field vs other powders in the same burn range? More than likely, no.

However, products that increase bullet speed sell, whether they be the magnum cartridges and the rifles that chamber them or the powder itself such as RL17, which boosts velocity in a variety of standard and some magnum rounds particularly in the WSMs.

So if RL17 can increase velocity while maintaining good accuracy in one`s particular rifle or rifles, then why not use it! It increases the barrel`s length by a few inches, without having to switch to a longer one.

It's not just trajectory. It's higher impact speed, longer effective range given a min impact speed, less wind drift, or using a heavier bullet with the same trajectory.

If its free for the taking, why leave 100 fps on the table? In the grand scheme of things, it matters very little. But then you would eventually get into the 300 WSM is just as good as the 300 win mag, but a 30-06 is just as effective as a 300wsm, but a 308 pretty much performs just like a 30-06, and so on. Pretty soon we will all be carrying 30-30's. And then what would we argue about?

I got the most "improvement" in using RL17 in my .284 Win. and heavier bullets.

That Shaw barrel is taper bored .0005" and only 19.5" long.

What does that do for the pressure curve and powders like RL17??

Tim

Geltlemen, I started this thread because I was hoping RL-17 would improve on H-4350. I was surprized to see H-4350 in my gun a 30-06 Tikka T3 was the better fit for both accuracy and velocity. I do believe I am the exception, not the rule. I will try the RL-17 in my 6.5x55 since it really likes RL-19.
Thanks Buckfever1

I used to shoot H4350 in my 300WSM's but switched over to R17 last Fall. Partly because Brad and others gave good reports and partly because H4350 was hard to find in any quanity last year.
The improvements have been fairly insignificant, velocity increased 25-50fps over H4350 and accuracy is similiar or maybe a little better. I've done quite a bit of shooting with R17 in temps from -10 up about 90F and it also performs much like H4350, pretty much good to go.

It is helpful to read about another 300WSM owner shooting Re17 and H4350. Shortly after Re17 was released I started testing it in two rifles, a 30-284 Ruger #3 and a 300WSM Kimber 8400. Both have 24 inch barrels. I shot over 300 rounds. They were all Barns TSX. 150gr, 168gr, and 180gr. Of these 213 were 180gr.

In each rifle I was able to get higher velocities from the Re17.

In the 30-284 shooting 180's I was able to average 91 fps faster shooting the Re17 but the velocities were erratic. The H4350 was more accurate. With a 2.5-8 scope set on 8x I was getting group average of 1.48in. @100 yds. With H4350 I averaged .94in. Deviation from H4350 at max pressure was hovering around 12 fps.
Because of the consistent fps and better accuracy I prefer H4350 for this rifle.

With the 300WSM I got some very high velocities shooting the Re17. I pushed it up to 3130 fps shooting the 180's. Brass life was only 5 or 6 reloadings. Again the average velocity got squirrely at these pressures. The other high pressure sign exhibited was cratering primers.

I could get 3060 fps with H4350 and everything was smooth. When I backed off the Re17 to the same velocity there were still some erratic chronograph readings.

For my two rifles I proved to my satisfaction that I could get higher velocity from the Re17. It would be less accurate and speeds would be less consistent then H4350.

I tried Re17, I liked it, would be very comfortable hunting with it, but returned to H4350 because in these two rifles it is for me more consistent and more reliable.

Thanks

Jim

One of the things that hasn't been mentioned about the often-mentioned strain-gauge results published on the the 6BR website is that the "200 fps gain" was in a limited capacity 6mm wildcat.

It isn't unusual for some powder to show a considerable velocity advantage in a round with much greater or lesser capacity than average for the bore diameter. This is because the selection of powders that might work is limited, especially with certain bullet weights.

Some other examples might be Ramshot TAC in the .350 Remington Magnum with 225-250 grain bullets, or IMR7828 in the .257 Weatherby with 120-grain bullets. This is because each powder has a burn rate and powder density that's particularly suited to that combination.

The RL-17 tests posted on the same website with 180-185 grain bullets in the .308 did NOT show a vast increase in velocity over a number of other powders already available. A little increase, sure, but not anywhere near 200 fps.

RL-17 is a fine new powder, and I've gotten very good results with it in several applications. But it would be unreasonable to assume a 200 fps increase is possible in every application, especially in cartridges in the middle range of bore/case capacity.

I worked up to Alliant's max listed at 66 grains with 180 grain bullets(300WSM). Way too hot for my rifles and like Jim, accuracy went to hell. That load might have increased velocity by 100fps(over accurate max loads of H4350) but it probably shot 2MOA.

Back it off a grain or two and things got (consistently)better.

400 yard load work-up.