New rifle, new load development, new brass, what’s wrong??

[ta6ppc]

So I got a brand new barreled action from a very well known and excellent gun smith, it’s 100% new Curtis Vector, with a 1:8 twist 22” Palma taper barrel. So I have some Berger 140 hybrids, and I ordered some new Peterson brass (small primer) I work the brass, weigh cases (all within 1.2 gr) , chamfer, deburr, weigh and length sort my bullets, now I get to the powder H4350 I started at 38 grains and went up .2 grains up to 40, at 38.2 grains I got an ejector swipe forming very faintly but no other pressure sign the primer isn’t even flatning and the bolt is still buttery smooth, I shot up to 40 which the bolt got slightly heavy on open and the primer was starting to get flattened and I stopped. So what am I doing wrong!

I looked at 6.5x47 data and it’s more in line with the Peterson brass just by looking at my case fill.. I wonder if I should just use 6.5x47 data with this brass.

I do not know the velocity as I no longer have a chrono but by the come up from 200-300 yards it’s inline with the 6.5x47 velocity on the higher end of the data.

good news is it shot everything excellent the target is at 200 yards and is 4 different loads with 5 shots each and that’s including the cold bore.

 

[ta6ppc]

Just to be clear ejector swipe started at 38.2 grains and got more pronounced as I went up to 40 grain, no burrs were raised just the dang swipe.

I shot some rounds I had loaded for another rifle which also pegged out in terms of pressure which are quite mild by the load data in any resources you can find.. kinda has me scratching my head as I had similar issues with my previous rifle.. maybe is a hot lot of H4350.. idk

 

[Ranger188]

It could be a couple of things, but you don't know the actual speed of the round,
and it seems to be shooting small. So whats the problem other than your seeing pressure?
A slow accurate rifle is better than a fast inaccurate rifle. If it actually is slow.

 

[littlebuddybr]

That☝☝☝☝☝

 

[ta6ppc]

It’s a 6.5CM, and I’m no where near book load with a speed of right around 2550 maybe definitely accurate and I’m very thrilled with the rifle

 

[acloco]

Picture of a couple caseheads would help.....

 

[joshb]

Ok, so we finally learn it’s a 6.5 Creedmoor but you still guess the velocity. Magneto speeds are pretty cheap.
Here’s a thought: You might be getting higher initial pressures while the barrel/chambering breaks in. Put a hundred rounds thru it and test again.

 

[Bill Norris]

There is a card included with the Peterson brass that explains the load may need to be adjusted due to case volume. My 260 brass is thicker than even Lapua and the weight is 5 grains more as well. This may be something to consider in the load.

 

[Ranger188]

You said this was new brass and "I work the brass"
What does this mean?
If you sized it new, it might have been a little short and might explain some early pressure signs.
38g is low, but low 40's is a good place to be. You might have a slow barrel and nothing you
do will help that. You also said this is a new barrel. Most barrels will speed up till they have
80+ rounds down them.
You didn't mention anything about the bullet jump. Was it jammed or a lot of jump?

 

[ta6ppc]

I’m seating the bullets around 2.9 overall which by my redneck measuring should be .010-.020 off

the brass I didn’t size, I ran 2 through the die and it didn’t touch or change anything, I just de-burred the outside of the neck and chamfered the case mouth with a vld Lyman tool. That’s all I did with the brass.

The case on the left is a low charge 38.2, the middle is the highest charge at 40, of course I reloaded them already so you can’t tell much from the primer, but they were not flat at all.

39.6 grains shot the best but definitely is leaving a nice impression on my new gorgeous shiny brass..

 

[WEL]

Peterson brass has less capacity. You will hit pressure sooner. That being said you should be able to get 2650 ish with a 22”. I get 2750 from a 26”.

 

[ta6ppc]

Peterson brass has less capacity. You will hit pressure sooner. That being said you should be able to get 2650 ish with a 22”. I get 2750 from a 26”.

I know it’s got less capacity, I’m just shocked that it’s more in line with what 6.5x47 data is, and may be a better source for data than actual creedmoor data.. that is for those who use Peterson brass

 

[acloco]

Will the ejector sit flush with the boltface when compressed by hand?

It IS possible, spring tension is too much or coil bound.

All three pieces of brass have ejector marks.



The historical data of trying to read pressure signs from primers is not consistent - most will say, don't. If a load is flattening, piercing, or enlarging primers, the load is quite a ways over normal operating pressure.

 

[INTJ]

You really aren't going to be able to diagnose anything until you get actual chronograph speeds. If that isn't an option, then take the most accurate load that doesn't have pressure signs and be done.

A chronograph is an extremely useful tool for load development. You might be at the velocity you want already.

 

[Bc'z]

Definitely need a chronograph report.
My 22" barrel gives me 2720 with 140gr bullets, hornady brass.
We'll see what the new barrel holds.

 

[6ShotsOr5?]

You really aren't going to be able to diagnose anything until you get actual chronograph speeds. If that isn't an option, then take the most accurate load that doesn't have pressure signs and be done.

A chronograph is an extremely useful tool for load development. You might be at the velocity you want already.

Agree with @INTJ. I don’t see anything wrong.

 

[ta6ppc]

So did a little digging and came up with 6.5x47 holds 46.9 gr of h20. With that said the Peterson brass holds right at 50 gr of water.. so I’m kinda thinking that when I go back to try and work up a load I’m going to use the 6.5x47 lapua data so I don’t trash my nice brass!

 

[basshusker]

What reamer was used and what is the neck wall thickness? May need to clean up necks for proper neck clearance?

 

[ta6ppc]

It was a sammi spec, .199 free bore

 

[ebb]

If you have a place where you can shoot to 400yds or more you can zero at 100 and shoot dead on at 400 and measure bullet drop. Put all the data in to a ballistics calculator and keep changing the speed till the amount of drop at 400 matches the program and that will give you the speed. Check the OAL of the cases and check to see if the necks are too long. When the lead pinches the neck down on the bullet pressure goes up fast. Good luck