Recent Experience with Peterson Brass- Neck Breakage and Brittleness

Due the math for the bushing size. You'll need the neck wall thickness x 2. Plus bullet OD added together less .002 for neck tension, should be your bushing size. The only problem is that the thickness may vary some from case to case. In the past I have found the different brands of brass the thickness is different from case to case. I found that in cutting necks to thickness. Now I cut all my neck to a thickness to start with. So that part of my formal for bushing size. I do this with new brass to start with. I don't use a mandrel to shape the inside of the neck to push the irregularity to the exterior of the neck after sizing. Not need after the neck has been cut. So that cuts down the working of the neck to set neck tension and moveing the irregularity of the neck thickness to the outside of the neck. annealing after each firing. Possible either not ennealing enough, or chamber size to big, plus working your neck part of the brass to much. As far as your primer goes I don't see anything wrong there. Picture enlarge is hard to tell any great detail.
You could also try some other brass manufacture brass to see how they hold up. To see if the problem carry on with the different type of brass.
This is how I figure the bushing size. Bullet OD .0308 + Neckness of ? or I'll use .015" per side x 2 for .03. So I have .308+.03-.002 for neck tension. Equal 0.336 bushing size. I believe my math is correct.
So it looks to me you are undersizing the neck by about .009".
 
A couple of years ago I had very much the same problem with new .223 Rem brass about 1500 rounds, loaded, and brass only... the brass had to be replaced by the manufacturer, they made it right, but... it was still a hassle. The brass was separating in the magazines it was so weak, not a good thing for your "go-to" ammo. Cheers

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I'm using, Peterson Cases in my New 6.5 Creed, Tikka with, Forster Dies,..
VERY accurate Loads with, ELD-M's and ELD-X's and NO Issues with, the Brass at 4 X fired, each !
The Tikka T-3X, 6.5 Chamber, is VERY Precise and concentric, as are, the Forster Dies !
Wish that, Peterson would make some,.. .270 WSM Brass
 
I have about 1000 case in 280AI presently. When I reading about the neck splitting. That kind of open my eyes up. I have had neck splits, but that was mostly not annealing my cases. At the time I was doing anything fancy either. The old case in a pan of water trick. Anneal once and never had a problem after that. Just primer pockets after that.
 
skipglo said:
I just checked 3 different 300 wm fired cases with .338-.341 fired dimensions. .331 sounds tight!.. Also crimping non- cannular projectiles can Dramatically spike pressure...albeit case head separations. As stated by others....DON'T CRIMP! Back that die off!
Click to expand...

This^^^

I came from the benchrest world. If crimping helps precision, every benchrest shooter will be doing it to win matches. Crimping has its place, but not for ultimate precision enhancements
 
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Idaho Lefty said:
I'm using, Peterson Cases in my New 6.5 Creed, Tikka with, Forster Dies,..
VERY accurate Loads with, ELD-M's and ELD-X's and NO Issues with, the Brass at 4 X fired, each !
The Tikka T-3X, 6.5 Chamber, is VERY Precise and concentric, as are, the Forster Dies !
Wish that, Peterson would make some,.. .270 WSM Brass
Click to expand...
I emailed Peterson and was told 270 wsm and 300 wsm brass were in the works with no date yet.
 
Veteran said:
My fired cases are .334 to .335.

I'm not sure what brand you have that are .338 to.341, but it may be brand or chamber differences.

I plan to stop crimping, yes, unless shooting hammers and may try again then. I will also check my loaded rounds OD w bullet seated and subtract .002 which is what Redding says to specify the Bushing.

But I note the minimum bushing Redding shows for .300 WM is .331, so I must have blown the bushing size at 327 for sure.
Looks like this is the issue causing to much contraction and expansion over working the necks.



1) New .331 or larger bushing
2) stop crimping
3) lube case necks for easier seating.

Thats my plan.
Click to expand...
I ordered a .332 size S type bushing this morning. I think these steps will put a stop to overworking the necks.
We'll see how many more firings I can get from the rest of this brass, and the next box.
 
MagnumManiac said:
Here are some more examples of stress fracturing, this 22-250 R-P brass was new when loaded, it had been left at at my Uncles farm quite a few hours away after I moved back to the big smoke. It sat there, in a MTM 100 round box for over 8 years, all but 15 of the 48 cases fired, split the necks and none went the full length, most had 3-4 splits around the neck and all were inspected prior to shooting. So this is either age cracking, or hoop stress from sitting loaded for so long.
Here's some pics.

Cheers.
Click to expand...
I have noticed that it I have loaded ammo that's been sitting for several years the number of cracked necks goes up a lot.
I wonder if in my case that it has gone through many hot and cold cycles for several years in the old farm house.
🤷🏼‍♂️
 
Veteran said:
I have always had excellent results with Peterson Brass, but after 4-5 firings on my .300 WM, I am starting to see necks
tear, sever, and become cracked.

I annealed this brass every firing.

The reason I switched to Peterson was case head separations above the belt in 3 firings, on the other brands.

I bump the shoulders back .002 every time, and have been careful not to over exercise the sizing die into causing fatique above the belts which is where I had problems before. Now, I have had no more case head separations and not even the tell tale circular cracking that comes just before it separates. Instead on about 5 of 50 of my Peterson cases, I am seeing cracks, and neck severing as in the pictures attached.

I am shooting the Peterson .300 WM belted regular brass, not the long brass. I am lubing the bullet bases with graphite powder prior to placing them in the necks to seat them. I have spoken to Muddyboots and he has recommended I lube the case necks inside before seating with case lube. I will try that next. I also have the Peterson .300 WM longs but have not tried them yet.

Now, the rifle I am loading for and firing these in is not a regular bolt gun, instead it is a bit of an odd duck, the TC Encore with switchable barrels. So it is a breach loader with some tendency to possible head spacing issues.

I'd be interested in hearing of any similar experience with neck cracking and failures on Peterson or other brass.
See the attached pictures. I took all of these out of my tumbler this last go round and then when I inspected them,
found these issues. I will definitely check my breech and bore on the rifle for the severed neck which is missing on the one casing.
Just in case......, no pun intended.:)

Yeah, that one that is severed and missing the neck looks like I left it in the trimmer waaaaaayyyyyy too long......:)

Until it was waaaaaayyyyyy too short!
Click to expand...
As opposed to some of you I do not anneal. I normally get between 3 and 5 loads per case which is apparently what others are getting when annealing. I find that Lake City military brass, 308 and 30-06 last the longest and since I shoot common ammo the loss of brass is not a life threatening issue like with other oddball cases out there. Not annealing simply saves me one step in the reloading process without, it seems, any loss. I should also note that I seldom load anywhere near max pressure finding the lesser loads more accurate at the distances I shoot.
 

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