Home Forums Reloading Big Game Rifles 7_08 Velocity

I ran some 120 Barnes and BT tips though my chrono last weekend. I had loaded R15 and Varget both at 44 grains. Varget Avg was about 80 fps faster with both bullets. I am going to re-run them soon but does that sound normal. Is varget that much faster.

Maybe I had a bad test?

Thanks

My Tikka is kinda slow with Varget, at least compared to reloading manuals. Nosler is aggressive with their data, for sure.



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Noslers BC's and book velocities wishful thinking.

Wouldn't think that 80fps would make any meaningful difference to anything. However, if it makes YOU feel better go for it.

I actually get a little better accuracy out of R15. It just Suprised me.

I'm shooting the 120 TTSX with 44 grs of RL-15 and getting about 2950 fps. Barrel length is 22".

Load which ever powder is the most accurate. In my rifle, it's RL 15. I haven't seen much difference in velocity between the two. I get 3000 fps +/- with 44 gr. of either powder in my 22" Cooper with the 120 grainers.

They used a 26" barrel for their 7-08 data. Which makes no sense to me, but there it is.

I can get up to 3100 with a 120 NBT and Varget at the max book load in my 22" barrel, but 3050 is the accuracy load.

If looking for velocity with 120's, try CFE-223, 2000MR, or Big Game. You won't be disappointed.

What are the specifics on your 2000mr load?

Big game will whoop them all.

80 FPS difference from book is nothing.

I've seen loads varie 300 fps from book.

If the books were accurate for your rifle, no one would need a chronograph.

No doubt.

CFE-223 will actually whoop them all. I have used Big Game in mine and Cfe223 is faster than Big game by about 90 fps and ES are more consistant than big game. My gun has a 20" barrel with 120 ttsx I am doing 3230fps. That is the max published load for cfe-223 for all the guys that will ridicule me about being over pressured or over max load.

CFE-223 will actually whoop them all. I have used Big Game in mine and Cfe223 is faster than Big game by about 90 fps and ES are more consistant than big game. My gun has a 20" barrel with 120 ttsx I am doing 3230fps. That is the max published load for cfe-223 for all the guys that will ridicule me about being over pressured or over max load. [/quote

Yep, I am .6 grains below max with CFE in my 22" x bolt and getting 3275 fps With the 120 ttsx. Max load on a 85 degree day was 3350 fps. Primers still had rounded edges and no problems with bolt lift or primer pockets.

That's cooking right there.

Velocity is your pressure sign..

Not really. Ever look at a pressure graph? Max pressure is only realized in the first few inches of the barrel. Then it drops rapidly. If you can extend the burn time at or near max pressure, you have more velocity. i.e. more area under the curve. I bet the gunpowder makin folks have used that technology thing to do just that.

Not in my rifle.

Seriously.. You're meeting and beating 280 AI, 7mm WSMs and RMs.

3350 fps out of a 08 case is nuclear hot, even with pixie dust and magic powder.

Either your chrony is jacked or you're a suicide bomber.

This is the kind of stuff that makes me skeptical of any "advice" I see on here about little cartridges doing the same things velocity-wise as big ones. Sorry to offend.I'm not buying it.

I'm not buying it either. No offense intended.

Good to know the eternal optimism of handloaders lives on.

Funny that the top velocity Barnes lists for the 120-grain TSX is around 3150 fps from a 24" barrel, but neither their latest manual or website lists any data for CFE223.

Hodgdon lists just about exactly the same velocity for CFE223 and the 120-grain Nosler Ballistic Tip--but doesn't list any for the 120 TSX. So I'm wondering where the "book max" came from?

Of course they probably don't list the REAL potential of any new powder....

DirtFarmer had 100 NPT's going 3,577 in his Swede.


























once.

He's loading some more.......primers were still round. He found 'em and checked.

Sure, the 3350 fps load was probably a little over pressure, which is why I settled on the afore mentioned load that runs 3275. You CAN NOT have "nuclear hot" pressure with zero pressure signs. I was skeptical after the first 6 round groups, so I loaded 6 more in the same brass, only neck sized(for the 3rd time) and they fit the chamber just fine. Primers were snug. Same velocity. I shoot about 10 different crappy rifles, so I know my chrony is at least consistant and in the ballpark. Btw this was a hodgdon book load for a 120 grain bullet.

Clever. Really. I am sad that after 14000 posts, you could not come up with something better.

I am not the only one getting these results. Powders are improving. Look at what the new Enduron powders are doing in the .243. 10 years ago, if someone claimed those velocities that are now tested, documented and common, you would have been flapping your gums just like you are now.

Define "nuclear hot." Are you saying it's impossible to be over pressure without overt signs?

I'd love to see someone run quickload on this, what was your barrel length again?

I'll stick with the load data currently at my finger tips. Nosler with their who-knows-why 26" barrel testing for the 7-08 maxed out at 3260 with their 120bt. Heck, Alliant was only able to push the 110sp to 3240...which probably doesn't matter as that bullet is history as far as I can tell.

Also, I was told long ago that primer cups indications are no fail safe. What if the primers cup happened to be harder than usual?

Plus, as has been said many times on here, dead is dead. 150 fps faster isn't going to kill them deader. Put it in the right place and get your knife out.

I am not giving any advice. I am only reporting what I have seen. I would hope one would be skeptical of everything they see on the Internet, then research and think things through.

"Nucleur hot" was Rancholoco's term, I was replying to him.
I think it very possible to slightly over pressure without obvious signs.
I think it is impossible to over pressure without signs to an extent that puts one in danger with a modern rifle.

The rifle is a 22" x-bolt.

For giggles...and yes I know it's quickload and there are limitations based on inputs. 22-in barrel, 2.8"OAL 7-08 Rem with 120 TTSX and 120 NOS BT.

120 TTSX first

Cartridge : 7 mm-08 Rem.
Bullet : .284, 120, Barnes 'TTSX'BT 28472
Useable Case Capaci: 47.971 grain H2O = 3.115 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length : 22.0 inch = 558.8 mm
Powder : Hodgdon CFE223

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-20.0 80 39.60 2593 1791 35723 8279 92.7 1.249
-18.0 82 40.59 2657 1881 38227 8518 93.8 1.214
-16.0 84 41.58 2721 1973 40919 8746 94.9 1.180
-14.0 86 42.57 2785 2067 43813 8961 95.8 1.146
-12.0 88 43.56 2849 2163 46926 9163 96.7 1.111
-10.0 90 44.55 2913 2261 50281 9351 97.5 1.077
-08.0 92 45.54 2977 2361 53898 9522 98.1 1.043 ! Near Maximum !
-06.0 94 46.53 3041 2464 57806 9677 98.7 1.012 ! Near Maximum !
-04.0 96 47.52 3104 2568 62030 9815 99.2 0.981 !DANGEROUS LOAD-DO NOT USE!
-02.0 98 48.51 3168 2673 66602 9933 99.6 0.951 !DANGEROUS LOAD-DO NOT USE!
+00.0 100 49.50 3231 2781 71563 10032 99.8 0.922 !DANGEROUS LOAD-DO NOT USE!
+02.0 102 50.49 3293 2890 76928 10111 100.0 0.895 !DANGEROUS LOAD-DO NOT USE!
+04.0 104 51.48 3356 3000 82718 10168 100.0 0.868 !DANGEROUS LOAD-DO NOT USE!
+06.0 106 52.47 3418 3112 89003 10214 100.0 0.842 !DANGEROUS LOAD-DO NOT USE!
+08.0 108 53.46 3479 3225 95848 10255 100.0 0.817 !DANGEROUS LOAD-DO NOT USE!
+10.0 111 54.45 3541 3340 103321 10291 100.0 0.793 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 100 49.50 3354 2998 86018 9618 100.0 0.859 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 100 49.50 3050 2478 57957 10051 96.0 1.006 ! Near Maximum !


120 NOS BT next...

Cartridge : 7 mm-08 Rem.
Bullet : .284, 120, Nosler BalTip 28120
Useable Case Capaci: 49.384 grain H2O = 3.206 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length : 22.0 inch = 558.8 mm
Powder : Hodgdon CFE223

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-20.0 78 39.60 2543 1723 33024 8291 91.7 1.295
-18.0 80 40.59 2606 1810 35334 8542 92.9 1.259
-16.0 82 41.58 2670 1899 37810 8781 94.0 1.222
-14.0 84 42.57 2733 1991 40468 9010 95.1 1.184
-12.0 86 43.56 2797 2085 43321 9226 96.0 1.147
-10.0 88 44.55 2860 2180 46368 9428 96.9 1.112
-08.0 90 45.54 2924 2278 49680 9615 97.6 1.078
-06.0 92 46.53 2987 2377 53225 9786 98.3 1.045 ! Near Maximum !
-04.0 94 47.52 3050 2479 57047 9941 98.8 1.014 ! Near Maximum !
-02.0 96 48.51 3113 2581 61169 10077 99.3 0.983 !DANGEROUS LOAD-DO NOT USE!
+00.0 98 49.50 3175 2686 65620 10195 99.6 0.954 !DANGEROUS LOAD-DO NOT USE!
+02.0 100 50.49 3237 2792 70422 10293 99.8 0.926 !DANGEROUS LOAD-DO NOT USE!
+04.0 102 51.48 3299 2899 75578 10371 100.0 0.898 !DANGEROUS LOAD-DO NOT USE!
+06.0 103 52.47 3360 3008 81147 10428 100.0 0.872 !DANGEROUS LOAD-DO NOT USE!
+08.0 105 53.46 3421 3118 87178 10477 100.0 0.847 !DANGEROUS LOAD-DO NOT USE!
+10.0 107 54.45 3481 3229 93721 10521 100.0 0.822 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 98 49.50 3304 2908 79031 9802 100.0 0.887 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 98 49.50 2990 2382 53056 10127 95.2 1.043 ! Near Maximum !

95,000 psi.....

My fellow, distinguished keyboard jockeys, I was/am not trying to push any limits here. As I said, the load I settled on is .6 grains below max on the hodgdon site for a 120 nbt. Sure, the velocity seems a little out there, but it is what I am seeing. (12 times for the max load, on 2 different occasions). Feel free to question my chrony, but I will tell you many different rifles have shot over that chrony and I personally do not have a reason to doubt it. For perspective, 45 grains of Varget and a 120 ttsx registers 3000 fps on that chrony. Seem about right?

You are pushing limits whether you are trying to or not. That's what everyone is trying to tell you.

Velocity is a very important indicator of pressure. There's no free lunch.

What everyone is questioning is your IQ.

The only one is seems about right to is you.

Wear safety glasses....

Load to velocity, not capacity.

If your load of CFE223 is at 48.9 and your getting those speeds then, I'd say you've got a real fast barrel...don't know what else to say. If it was me, I'd see if someone would let me run that load over their chrony, just to see what a different chrony would tell you.

Your varget load seems about right IMO, based on your 22" barrel, etc.

Would be willing to bet he's using a Shooting Chrony. Have seen one of them jump 10% in velocity due to a change in the light.

The magic new velocities (which amount to maybe 100 fps) in the .243 with Enduron powders are most likely due to using more accurate piezo-electronic pressure-test equipment, rather than older copper-crusher equipment. If you look at Hodgdon's data on their website, it shows the pressure for the Enduron powder in PSI (electronic) rather than CUP (copper crusher. Hodgdon has not made any claims about higher velocity levels with the Endurons.

Apparently you don't have the iq to understand that velocity DOES NOT EQUAL pressure. It can be an indicator, but only when variables don't change.
PRESSURE OVER TIME minus whatever resistance the bullet encounters, blowby, etc. Determines velocity. You have no way of knowing the TIME variable. You could, in theory have a load with half the peak pressure of another, but still produce more velocity. Simple physics. Peak pressure occurs in a very small portion of the barrel. Do you think that in the last 50 years of powder development, they juuuuust may have found ways to improve burn characteristics? i.e tweaked powders to have longer sustained burn at lower pressure? Or were they too busy going to the moon?

Found 6 example in 5 minutes of people getting similar results with cfe and ttsx.

BS they use psi in half of their listed loads
And you think their testing equipment has improved, but nobody will ever improve powder?
That is funny/sad.
You are just sore that none of the improvement benefit long actions

I would love to run it over another chrony. If I do, I will report back

Not quite. The work done by an expanding gas is pressure as a function of volume, integrated over volume.

w = ∫p(v)dv

This can be parameterized using time t, but the pressure-time curve by itself doesn't tell the story.

You are a prize.

I just looked at the Hodgdon 100-grain data for the .243 and the ONLY pressures in PSI are for the Enduron powders.

I know companies improve powder, because they send me samples all the time to test. BUT, as I stated already, Hodgdon isn't making at claims that the Enduron powders get any "extra" velocity than other powders. All the improvements are in other areas, such as temperature-resistance, a decoppering agent, and "green" ingredients, so they can sell them in Europe.

slim' if the 120 TTSX blew up on your doe in 2012, why are you back again pimping the same load?

Edit: if pressure does not equal velocity, what pushes the bullet through the barrel, CFE 'pixie dust?

I get your drift, but it is quite possible for two loads producing the same velocity to have different peak pressures. Similarly it is quite possible for two loads having the same peak pressure to produce different velocities.

Yes...some of that variation can be due to a different bearing surface length and/or metallurgy in the gilding metal...or whatever type of alloy the bullet is made of...

It matters not what they claim, that argument is laughable, the proof is right there in the data. Powder has been/is improving.

To your next nitpicking point, I was looking at the 85 grain tsx data where EVERY LISTED LOAD IS IN PSI

Are you referring to my post?

yes...sorry I don't know how that got crossed.

Slim,

That's because they switched to piezo equipment within the past few years, so started testing every new product (whether bullets or powder) in PSI.

They didn't run nearly as many powders with the 85 TSX as they have with older bullets, particularly in the slower burn-rate range where IMR4451 stands out. Check out their .243 data for the 90-grain Speer bullet: the velocities for 4451 lag behind such "new" powders as H4831 and H414/W760.

Have you ever actually done any work with pressure-testing equipment, whether strain gauge or piezo-electronic?

OK. I wasn't addressing changes in component bullets. What I wrote is independent of that consideration.

I'm not pimping anything. Just sharing what I have seen. Is that so hard to understand?
This ain't a bullet thread slick. The ttsx destroyed that doe's heart. All I said is that I was surprised it did not exit. Btw ttsx might lose petals, but they can't blow up. The thread is about velocity, so I think it's relavent.

Sure, understood. I was sharing that to acknowledge that there's lots of factors that can change in the equation of velocity. I didn't explain that well.

Please put your comments outside of the quote box, or color them, so I can follow them better.

It's area under the curve all right, but you still haven't latched on to the fact you're talking about the wrong curve. Work done, and hence velocity, is through the area under the p-v curve, not the p-t curve.

Calculus was brought in precisely because that's how area under curves is described in other than simple situations.

[color:#FFFF66][/color] I have worked with strain guages in both destructive and non destructive testing, never in a pressure vessel application. I never said newer powders were better in every application. Are not we talking about the 7-08 and ttsx? How about Superformance, in some calibers, nothing touches it.

Well, this is a simple situation where i was trying to keep an explanation simple. what am i missing? pressure times the area is force. simply put, the average force (however you want to arrive at that) exerted over the time the bullet is in the barrel will give velocity when bullet weight acceleration are figured. BTW The area under a curve with pressure in the y axis and time in the x-axis will give the work done on the bullet. what is it you think I am not latching on to? - how to open up my physics book and write some equations? Thanks for your "help"

Not directly it won't. That's what you're not getting. The work done is area under a pressure-volume curve.

It'seems scary that you think magic powder makes a 7/08 into a 7mm RM.

Look at the velocities in the book for your load, and the quick load figures above.

Once again, either your chrony is jacked or you're about to blow yourself up.

Please realize chamber, brass, and throat can cause your rifle to reach pressure way before book max.

Reload for velocity not weight and capacity.

mathman, that was not directed to you.

'slim, by default this is about bullets as one component of the subject.

You stated you may be a little over pressure at ~3350, I am guilty of pushing 61-63K psi close to 68K psi, I don't think I have hit over 70K but I damn sure have no intention of pushing it into the mid-80's.

A running start increases velocity, a slicker bullet increases velocity with more powder, higher peak pressure under a longer curve increases velocity; and, higher peak pressure can increase velocity.

I think all who have commented on the velocity you are achieving now and in the past, are showing concern, take it for what it's worth.

Bottom line, if you take a pressure time curve, and increase the area under it, all else being the same, THAT BULLET IS GOING FASTER. Shall I post a curve for you?

I truly appreciate genuine concern, it is just hard to see it through smart a## and condiscending comments (not directed at you). Lots of people are getting these numbers.
I just have a hard time seeing my pressures are that high with a load .6grain below max on an identical weight bullet.

Natural selection at work here, folks.

Slim,

SOME powders produce the highest velocities in SOME cartridges. While some of those are newer powders, some aren't--and so far there's always some other compromise being made.

"The" Superformance powder in various Hornady factory loads is actually several different blends of similar powders, each formulated to produce the most velocity in a specific cartridge, or even a certain cartridge/bullet combination. The Superformance sold to handloaders is the .30-06 blend, and yes, it does produce more velocity in certain specific instances. But that's been going on for a long time, with a lot of different powders.

If you check out loading data for various cartridges, there are always certain powders that produce the most velocity in certain combinations. IMR4350 is now 75 years old, and its still at or near the top for certain applications, despite being a single-base powder.

A few years ago Reloder 17 was supposed to be the new magic super-velocity powder. That lasted until Alliant published actual pressure-tested data. While RL-17 does do very well in specific instance, so do many other powders. In fact, it turned out that even some of Alliant's other powders beat RL-17.

One other interesting fact that can be learned from actual pressure testing, instead of the pressure guessing many handloaders (like you) depend on, is how often traditional "pressure signs" don't show up until 70,000 PSI or even 75,000 psi. And that's in temperature- and-humiditycontrolled laboratories, not out in the real world where it isn't always 70 degrees, and the bore may have some moisture inside.

That's exactly why SAAMI standards leave some wiggle room. They don't want some handloader running pressures up to the absolute max, and then when conditions change their "safe" load somehow isn't as safe as it seemed the day they worked it up.

Your post speaks to your character. How original. Neeeever heard that one on the forums before

So you are saying you do not think powders have been and are improving?
By the way, what powder do you think is at the top velocity wise for that 90 grain Speer data you were talking about? Hybrid 100v introduced in 2012.

I would love to see evidence of brass and primers not showing pressure until 75000 psi.
I am not being argumentative here, I would like to understand it. Either the pressure is enough to flatten a primer, or it isn't ( all else being equal) if that isn't the case, I would love to why.

One place pressures can get high before brass starts to show signs is in a "balanced & blueprinted" action and chamber where everything is true, square, and minimum dimension.

One instance where this was apparent was when Layne Simpson used a Jarrett built rifle to develop 7mm STW loads for his article years ago. Pressure lab tests revealed how hot his stuff was when the cartridge was being subsequently standardized.

How much pressure does it take to flatten a primer, and are all primers equally resistant to deformation?

Really? Why is that?

Are you saying I'm a Darwinist?

You're The ape, you tell me

someone said that I was trying to duplicate the performance of a bigger case. (Which I care nothing about, I just posted results I have seen and all of a sudden people are reading things in to it. If it wasn't you, then my mistake.)

THAT would be good to know. I know that primer cups differ in thickness and have different properties. That is why I said "all else being equal." I also know that headspace plays a role in primer flattening. I have seen write ups correlating case head expansion to pressure, but I have never seen anything on primers in controlled conditions.

Slim,

As noted in my first post on powder, nothing is free. The tests in Hodgdon's data are shot inside temperature-controlled rooms at 70 degrees. Yes, Hybrid 100V is the "fastest" powder with 90-grain bullets (by exactly one fps over H4831), but H100V is also one of the less temperature-resistant powders I've ever tested. In a trial a few years ago with several powders and 165-grain bullets in the .30-06. H100V lost 176 fps between 70 degrees and zero Fahrenheit.

Since H4831 is one of Hodgdon's Extreme powders that are very cold-resistant, it doesn't normally lose any velocity between 70 and zero, which means that the "advantage" of oh-so-modern H100V would disappear with a drop of about half a degree in temperature. I've found this sort of temp-sensitivity to be common among newer powders designed to produce top velocities at 70 degrees.

The REAL advances in powders haven't been extra velocity as much as other characteristics, such as consistent velocities over a wide range of temperature.

That was my point. Absent that, it would seem that they're not very reliable indicators.

Seeing those results on a chronograph, and nothing "happens"( no outward signs of pressure) is what we get when a bunch of amateurs (us) gets turned loose with a bunch of powders full of promise and a chronograph, with a million variations in components and barrels,and some pet cartridge.

If you do this stuff often enough eventually we run into these velocity anomalies,there are no outward signs of pressure we can detect with our "guessing" techniques and we think everything is fine and some miracle powder gives these results.

Just as examples,similar situations I've walked away from include: 3200 fps from a 22" barrel 270 and a new lot of RL22; 3100 fps from a 150 gr in a 23" 30/06 barrel and H205;3300+fps from a 160 AB in a 7mm Mashburn and a load of Retumbo;one 7 Rem mag that gave close to 175 fps more velocity in one rifle than another with the same load of H4831.

There have been others but the point is that familiarity with the cartridges and lots of data told me those velocities were over the top,even though there were no outward signs of pressures to indicate I was over the top.Those are the kind of loads that will sneak up on you one day,or leave you in Montana on a hunt with a seized up action or worse. Bad practice.

Dunno know about anyone else but when I try to figure what a cartridge will do I don't look at the max velocity in a manual or what one person got without getting into trouble....too many variables and you have to leave yourself some wiggle room. Just because we see these velocities,even with manual loads,does not mean they are safe in our rifles.

It means we are redlined and a small step or slight variation away from bad stuff.

Pushing a 120 TTSX another 200 FPS gets you 7" less drop, 2" less drift, and an additional 154 FPE at the 500 yard line.

Not even worth the [bleep] effort...

16 Sure.....advantage is small.

Point being it isn't worth chasing it in the little case just to show you can reach velocities with it that you won't see anywhere else credible.(pressure tested). You aren't breaking any new ground or proving a thing....just stuffing more powder in and it doesn't take any brains to do that.

If we want it,then we can have it.....just buy a bigger cartridge.

Of course this may require compromises like a longer or fatter case,a slightly heavier rifle, etc. Part of the game.

I believe there's already a thread about how difficult it is to manage an extra 12oz or rifle.

smokepole,

General Hatcher mentioned the unreliability of primer appearance as a pressure indicator in HATCHER'S NOTEBOOK, first published in 1947. He knew a thing or two about pressures in rifle ammo, since he was one of the U.S. military's top ordnance officers for many years, the reason he was Technical Editor of AMERICAN RIFLEMAN after his retirement.

Unfortunately, he didn't go into any detail about why primer appearance is so unreliable, apparently thinking the reasons were obvious--such as varying thickness in primer cups, added to variations in headspace. I've got a collection of old issues of AMERICAN RIFLEMAN and am slowly going through them, among other things looking for details to his statement about primer appearance. Will post them if I find any, though among many Campfire members the opinions of dead guys don't matter, because their post-count is so low.

Wasn't chasing anything. Started below published load data. Not sitting here saying hey look at me. Not trying to take any credit. I did not design the powder or the rifle. Just posted what I saw and considered interesting. Quit reading so much into it, it makes you look like you have a complex about it! just kidding, I know most of you guys are concerned about the safety aspect.
On a side note, here's a hypothetical. You try this new powder. 7-08, 120 ttsx. You are not seeing any pressure sign. Velocity is very high and you are not near max. Exactly what velocity do you stop at?

Yep, and they also never post pics.

Personally, if I had data for the bullet I was shooting (not a different 120-grainer) I'd stop at the max "book" velocity, regardless of the powder charge, taking into account any difference in barrel length.

Based on the theory that my rifle is at max pressure when I see max velocity.

Did you notice the h100v load had less pressure as well. Varget was a leap and not very temp sensative. LVR in the 30-30 was a big leap. I agree a lot of these new powders are not perfect, but I fail to see how they are not getting faster. That was my only point.

Basically what Smokepole said. I'd look at as many sources as i could for that bullet,and even others of the same weight noting barrel lengths, etc. I'd likely back off to to roughly the top velocity,give or take. Watch accuracy.I'd be looking for a weighted average in terms of velocities and consider anything I didn't see in a manual as an aberration or goof up on my part from going too high....kind of an "OOPS!".

I'd take 5-10 cases, fire them several times,and watch velocities and check for primer pockets opening. If the load passed all these touch/feely tests I'd say I'd be good to go.Not the most scientific of methods but maybe the best we can do as basement hand loaders.

I'd also compare powder capacities of cartridges a step up, in size....say a 280 and 280 AI in the case and see what they are doing.If I am equalling or exceeding the velocities of those cases I'd be looking for the reason.

My concern is always mono's vs jacketed of the same weight. But it aint my rifle.

Slim,
Take the above to heart. This is the point everyone is making.

Bam.

Yep.


Or any other variable that will change the bearing surface.

I will generally load to book maximum velocity if I can get there with no obvious signs of pressure.
If that is the case I will proceed carefully until I do notice pressure then back off accordingly
The main thing I am looking for is incremental increases in velocity, as soon as this diminishes I believe an over pressure situation is occurring, often noticed just before bolt lift comes into play.

Good strategy...... but with the double based propellants I've worked with the velocity doesn't flatten out (diminish at top end); with double based powders like RL22,you add more powder and you continue to get more velocity even in the red line zone.

Meantime you are already over the top and don't know it but velocities are atypical but we think they are OK. You hang out on the ragged edge of pressure and performance.

I go the way of my BR bretheren and let the groups decide, not the chrono. Load data is a hoot.

How much powder?

"2 more clicks than last time"

Sorry, didn't see this earlier. 49.0 gr using 120 gr TTSX in a 24" barrel gave cloverleaf groups and 3130-3150 fps. I went up to 49.5 gr and velocity went up as you would expect (3160ish) but accuracy suffered. Hornady lists 50.0 gr as their max for 120 gr bullets with 3188 fps in a 22" barrel. I had zero pressure signs with either of these loads.