Peterson Brass &&^^%$##$%

[Spotter's Signature]

Some already pointed it out: Peterson brass is thicker than many other, so it has lower volume. This can get extreme: in my 7mm WBY, I max out velocities almost 2 full grains of powder lower than listed in official sources.
Here's an additional problem: it is recommended that in load development involving copper mono bullets (due to "differences in their construction"), you must start actually at the low end of the recommended charge. I frequently pick the mid charge to start, "to save time and resources", haha... I got lucky I maxed out at the very first charge I scanned, which was the middle charge. It could have gone over pressure.
As to the brass, I'm on 15th reload using 300 WM Long brass (there were some issues with tight primer pockets initially, no problem though), fantastic cases. 7mm WBY MAG... Extremely expensive; high quality and consistent, but I just noticed the first neck split on a 4th reload. It never happened in my 300 WM, but there are many reasons why this can occur.
As to tight chambering - carbon ring was my issue before; thorough cleaning took care of that. If it's not the rounds, there must be something going on in the chamber.

 

[orkan]

I have never needed to FL size or mandrel Alpha before loading.

There are guys winning Fclass, benchrest, and PRS/NRL matches pretty frequently with brand new Alpha straight out of the box, no prep, untouched.

I've shot it straight out of the box for 100 shots recorded, with the worst group measuring .3's and the average being very low .2's.


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[waspocrew]

Out of the box, my Alpha 22 Creed brass needed a mandrel to open them up. Otherwise, seating pressure was deforming projectiles, despite chamfer/deburr. I ran a mandrel through them and the problem cleared up.

 

[Aoudad 101]

Did you load 7mm.bullets?

 

[lacajun]

I have never needed to FL size or mandrel Alpha before loading.

There are guys winning Fclass, benchrest, and PRS/NRL matches pretty frequently with brand new Alpha straight out of the box, no prep, untouched.

I've shot it straight out of the box for 100 shots recorded, with the worst group measuring .3's and the average being very low .2's.
I have done the same in my 6.5 CM and never had an issue. Threw 42 grains of H 4350 in the cases with some 143 eldx just to form fire and shot all over .5

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[QuietTexan]

If Alpha would make 223 Rem and 220 Russian I wouldn't ever need Lapua again. I've gotten tight Lapua cases that need a mandrel to open the necks, and got a batch of 6.5-284 Norma that had donuts out of the box. Still good stuff in general but every rule needs an exception to prove it I guess.

 

[Mike D Texas]

No issues with Peterson at all and I shoot it in multiple cartridges including 260 Remington.

 

[Hardshot]

If Alpha would make 223 Rem and 220 Russian I wouldn't ever need Lapua again. I've gotten tight Lapua cases that need a mandrel to open the necks, and got a batch of 6.5-284 Norma that had donuts out of the box. Still good stuff in general but every rule needs an exception to prove it I guess.

Lapua ,Peterson ,Norma , Alpha I treat the process the same .Check an empty in chamber for fit and headspace . Neck turn them all to clean up to a consistent thickness then size , chamfer and fire form .
I also wish Alpha made 220 Russian. I would definitely try them . I hear that Alpha makes 6 Dasher .My friends say it's not fully formed at shoulder and still needs fire forming. I don't have any experience with Alpha in Dasher

 

[lacajun]

I have never needed to FL size or mandrel Alpha before loading.

There are guys winning Fclass, benchrest, and PRS/NRL matches pretty frequently with brand new Alpha straight out of the box, no prep, untouched.

I've shot it straight out of the box for 100 shots recorded, with the worst group measuring .3's and the average being very low .2's.

Thats right ive shot about every brand right out of the box to form fire...including lots of peterson in 6.5 creedmoor and 308 never had an issue. Just odd to me I had the issues with the 260 stuff.

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[lacajun]

Thats right ive shot about every brand of brass right out of the box to form fire...including lots of peterson in 6.5 creedmoor and 308 never had an issue. Just odd to me I had the issues with the 260 stuff.

 

[Eric H]

Thats right ive shot about every brand of brass right out of the box to form fire...including lots of peterson in 6.5 creedmoor and 308 never had an issue. Just odd to me I had the issues with the 260 stuff.

So how did you remedy the problem?

 

[Old Rooster]

21st Century has Mandrells and the die to hold it.Not expensive at all.
I bought the Nitrided Mandrell as it don't need lube to make it work well.Slicker than snot on glass.
After using a bushing die to get neck tension I use the mandrell to push all neck irregularities to the outside of the neck.Makes a big difference!

Expander Die Body

Expander Die Body Introducing the much anticipated Generation X Expander Die Body with viewing window! Set up of an expander die has not been easier! The viewing window allows the user to set the die to allow for optimal mandrel use without “bottoming out”. Machined out of 7075 Aluminum and...

21stcenturyinnovation.com

 

[thomasbangs]

Learned my lesson over 50 years ago, always resize new brass regardless of the manufacturer. I have also found although rare that sometimes brand new brass was over length after sizing. I have loaded some. 223 Remington that was sized and trimmed and ready to load, I run them through a cartridge headspace gauge first to make sure.

 

[BillLarson]

will an empty piece of pete.brass chamber without bullet....????