High Pressure Issues (Help)

[pacrat]

A couple months ago I helped a fellow calguner develop a hunting load using the same components,with the exception of a 165gr Sierra Gameking.
He wanted to start at the bottom of the load spectrum,but I suggested something closer to the middle to eliminate 50% of load development.He settled on 40gr IMR4064.A phone call later said his rifle shoots nice little holes exacetly where he wants them.By the Sierra book which we used ,40gr is 3.5gr less than max.

So you went against long established common sense safe practices, got lucky and no one was hurt.

Congrats. You made Bill Engvall's list.

[buffybuster]

head space correct

How are you verifying this?

[Coyotegunner]

Not saying my following statements will fix it:

Some rifles are more special than others or the majority.Maybe you are just lucky on yours.

I have a example of my own:This nice little custom I own in 22-250 built on a Mauser action would shoot any factory load fine.
I reload pretty much for 34 calibers.I know sick huh.
That 22-250 with any brass full length sized would flatten primers.BAD.
I ran 40 gr bullets 10% below the minimum load to stop it at first.
I had the barrel recut at the action and rethreaded and reinstalled.Did not help.
I switched to CCI primers(yes they are a harder cup)Got the loads up to the minimum charge rate but over that,flattened primers again.Sh*t&#*^#.
Bought a neck sizer only die.Got the loads up to the middle charge rates.
OK I stopped here.
It is wonderful accurate.
I just want neck sizers for all my loads now.

You could try backing off your full length sizer a little at a time,checking each brass until you reach the happy spot where it still closes the bolt.

In my words from recollection:Brass jumps forward then back until the bullet leaves the barrel.When it goes forward,the primer pokes out,then slams back home when the brass comes back and flattens.I actually borrowed this statement from a Hornady book.This is not their wording but gives the idea.

Just calling out the disclaimer here:Hope you can try maybe one of these things and remedy your problem

Edit:And yes the bolt would stick in that gun before the experiments.Of the several 22-250s I own,the one I mention above is the only special one.

[bsumoba]

I saw first hand another guy shooting 4064 with PPU brass in a 308 bolt and was getting sticky bolt like crazy. My assumption is that he loaded a whole bunch of different brass with a so called "safe" load and went to the range...bad idea. ALWAYS WORK UP THE LOADS! If you switch brands of brass, another load workup is recommended/required.

I stay away from PPU brass and I actually stick with one headstamp (LC 10) brass and load for that headstamp now.

You have to also remember that book charges are using a specific bullet, brass, primer, OAL, etc.

I have to ask...did you make sure it was 4064 and not some other powder? did you make sure it was IMR 4064 charts you were looking at and not Accurate?

[elk hunter]

CBC brass gave me almost the exact same problem "sticky bolt" with a middle of the road load in my .308. Every case of the CBC did this, same load in Winchester or Remington or most other brass DID NOT have this problem. All of the CBC brass I had went into the scrap brass can.

[Fjold]

Do you have a chronograph? If so, does the velocity fit the load data?
Is the recoil excessive compared to factory loads?

[J-cat]

CBC brass gave me almost the exact same problem "sticky bolt" with a middle of the road load in my .308. Every case of the CBC did this, same load in Winchester or Remington or most other brass DID NOT have this problem. All of the CBC brass I had went into the scrap brass can.

Have you considered that Win and RP have way more capacity than CBC which is the heaviest 308 case on the market?

[pacrat]

this load is telling you too hot no matter what books say back off 1 grain or more. your gun is telling you listen to it.

+1

All cases are NOT created equal

[elk hunter]

On another possibility the brass just might be softer. I've seen the same problem with to soft a brass. Yes I considered that the CBC was a thicker brass and it was loaded with the 1-2 grains lower than commercial brass was loaded with which is the rule of thumb for loading the thicker military brass.

[Pauliedad]

I've been using PPU for a while and just started to work with CBC.
I went to what was a light load to start with for the CBC and have gotten moderately flattened primers. I know weight is not conclusive, but the CBC are considerably heavier than the PPU telling me it's thicker and thus, less volume = higher pressure.
I wish it wasn't so but it's clear I will need to have very different loads for those two types of brass.
I can also see how it might be possible that CBC may be softer but in my experience, there is slightly more resistance when resizing CBC compared to PPU.

[hylander]

I have went over every thing mentioned here, thanks for the input.
I picked up a few Win. brass and made up a couple more loads, won't get to try them until next Monday.
Checked case capacity between the Win brass and the CBC, the CBC definitely has less case capacity, easy to see with just the eye.
Also I loaded the first batch in my garage and the scale was really cold, I'm wondering if that had any effect on its accuracy.
Been loading for over 20 years so this ain't my first rodeo but first of this issue.

[toby]

Toss the brass and quit crimping if you are.

[hylander]

Toss the brass and quit crimping if you are.

Just got through tossing the brass, and I never crimp my bolt rifle loads.
I also noticed with the CBC and PPU brass there was a lot more resistance when sizing than with Win. brass.
Also I checked case capacity. These were all FL sized, trimmed and primed.
As you can see, there is a big variance from CBC to Win.

With HP-38, I used this because it meters well and will settle well
in the case.

CBC: 40.2 gr.
PPU: 41.1 gr.
Win: 42.2 gr.

With Water:

CBC: 52.4 gr.
PPU: 54.0 gr.
Win: 55.5 gr.

[J-cat]

That's pretty much it. I dunno why you're tossing the brass when you can simply reduce the load.

[elk hunter]

Brass can be a very different world I have seen the much touted Norma brass come out of the new box with cracked necks, brittle necks. Around here somewhere I still have some .257 Roberts "Norma" brass that on the first shot with a starting min. load blew the primers completely out. The loads were right, it was new but bad brass. It happens.