Higher pressures with 1x fired brass?

hunter24605

hunter24605

Handloader
Apr 30, 2016
2,365
3,613
I used up my supply of virgin brass and when I sized, trimmed, prepped, etc and loaded with the same loads from when it was new, I get pressure signs MUCH sooner. Not really sure whats happening here. Unless my FL die is out of spec? this is in a 270 wsm. I ordered a Wilson case gauge, so maybe that will shed some light on things. I've also noticed it takes considerably more force on the ram handle to size than it does with any of the other cartridges.
 
Have you checked the case length. I'm thinking maybe the case mouth jamming into the rifling not allowing the case to release the bullet correctly.
 
hunter24605":hah45nu3 said:
ShadeTree":hah45nu3 said:
Higher pressure signs in what way? Flattened primers?
Click to expand...

Hard bolt lift and ejector marks, slightly flat primers
Click to expand...

Flat primers I had some theories, but the other 2 are classic signs of overpressure. Nothing else has changed? Same OAL, powder, bullet, and charge weight?
 
ShadeTree":1f9ppynp said:
hunter24605":1f9ppynp said:
ShadeTree":1f9ppynp said:
Higher pressure signs in what way? Flattened primers?
Click to expand...

Hard bolt lift and ejector marks, slightly flat primers
Click to expand...

Flat primers I had some theories, but the other 2 are classic signs of overpressure. Nothing else has changed? Same OAL, powder, bullet, and charge weight?
Click to expand...

The only thing that has changed is I cleaned the barrel with wipe-out, and the rifle only has about 50 rounds through it, so I doubt a carbon donut has formed. Same trim length, verified charges with the beam scale, same OAL, same box of bullets and same lot of powder and primers..I should say this is a new set of dies that haven't been used until now...I found 3 more pieces of new brass that I saved for dummy rounds, but never got around to seating a bullet in them. So I'm going to load them up and see tomorrow.
 
BruceP":1fde7zix said:
Have you checked the case length. I'm thinking maybe the case mouth jamming into the rifling not allowing the case to release the bullet correctly.
Click to expand...

Yeah, i use the Lee trim die and verified by measuring the trimmed pieces, and they are spot on with the new brass.
 
Hunter, you seem to know what you're doing so I'm not trying to ask redundant questions, but just trying to make sure there's not something you weren't thinking of.

You trim before or after sizing? If before, you double checked the case length after sizing?

What does the case head of a sized case measure just ahead of of the extractor groove compared to the new brass, or better yet sammi minimum cartridge spec for that cartridge?

I had a undersized die once and that's how I nailed it down. What got me looking is exactly what you were saying about taking a lot of effort to resize cases. It wasn't making pressure on reloaded cases, but then again I was loading a fairly mild load. Sent the die back to the company and 1 of the machinists called me and confirmed I wasn't off my rocker and sent me a new die.
 
ShadeTree":2qgk55t8 said:
Hunter, you seem to know what you're doing so I'm not trying to ask redundant questions, but just trying to make sure there's not something you weren't thinking of.

You trim before or after sizing? If before, you double checked the case length after sizing?

What does the case head of a sized case measure just ahead of of the extractor groove compared to the new brass, or better yet sammi minimum cartridge spec for that cartridge?

I had a undersized die once and that's how I nailed it down. What got me looking is exactly what you were saying about taking a lot of effort to resize cases. It wasn't making pressure on reloaded cases, but then again I was loading a fairly mild load. Sent the die back to the company and 1 of the machinists called me and confirmed I wasn't off my rocker and sent me a new die.
Click to expand...

One of the guys at the range has the same set and a little bit ago he brought by his FL die and it's smooth as silk and doesn't require near as much force, and doesn't leave the striations on the brass like mine does. So I'm boxing this up to return.
 
Sizing the new cases and sizing the 1X cases with the same die,
Thus case capacity should be same?!

BUT, sometimes crazy things can happen reloading.

Try filling the sized new cases and the 1X sized cases with water.
Weigh cases to see if weight of water is different between the 2.
 
New cases are usually quite a bit undersized so they give a lot on the first firing. After they are fully formed that changes and it's not uncommon to have to lower the powder charge. Most of the time the lower powder charges still have about the same velocity.
 
Agree with Idaho! I've had several calibers do me that way. If I set up a great hunting load in new brass, I'll load up 40-50 "in new brass" and set aside just for hunting, checking zero before the hunt, etc. I then will play with the fired brass and tweak if necessary. Sometimes I will try a new/different bullet weight or style and if I'm using fired cases, I'm there already. I keep it all separated.
 
IdahoCTD: I usually have the opposite results. New cases have less volume than fired and sized cases. It takes more powder in fired and sized cases to achieve the same in new cases.

Preacher: Yep I always do my load work up with cases that have been previously fired. Learned this a loooooog time ago with a new Rem. 700 7 mag. Thought the rifle was a lemon because it would not shoot any load, bullet, I tried while only using new cases. When I ran out of new cases I just part sized, neck sized with a FL die, the best previous load that shot 1 3/4" and BINGO 5 shots in the same hole. That rifle was a tack driver with most anything you put in it as long as it was a case that was previously fired and part sized.
 
SOLVED:
I've been away from the site for a few days, but I found the cause of the pressure issues..Although the FL die was tight, that wasn't the issue...I measured a few of the trimmed pieces of 1x and about 5 of the 15 I sized were too long..Inspection of the trimmer showed a crack in the plastic ring allowing the "stop" to slip past the Max length setting. I used another trimmer and re-tested the loads and the pressure signs went away. I'm assuming that at some point after setup the die trimmer slipped so some were right and some were too long..I usually measure about every 10th case, but since I was only doing 15, I didn't measure any after the first few were right.
 

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Glad you found that problem. I just could not believe a previously fired sized case would have less case capacity than new cases. In over 40 years I have never seen that. I almost ruined some 223 cases once when the stop collar on my Lyman trimmer slipped which cased the cutter to cut too much off the neck. Only ruined about 3 cases before it dawned on me that "this seems like this is trimming an awful lot off these cases." Measured and found the problem before ruining more.
 
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