Does Atlas .300 Win Mag Brass headspace on the shoulder datum or on the belt as tradition ?
Peterson 300WM Brass?
- Thread starter Muddyboots
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Does Atlas .300 Win Mag Brass headspace on the shoulder datum or on the belt as tradition ?
Impossible to find ADG brass which is why I bought the Peterson. I am on so many notification lists for ADG I could not ell where I signed up!
I have a question, because I don't know the answer, and I need too. Will the long brass make a huge difference in the way our rifles shoot? What are the advantages of the long brass? The reason I am asking is I think I'm going to try and cancel my order and just wait for it to come back around.
See this description from earlier thread.
Link: Peterson 300 long
Link: Peterson 300 long
Now that you reminded me, I do remember reading that before, but I guess the significance of that article did not really sink home until I read it again. Thanks for helping me understand this better. I will cancel my order and wait for the better long version to come back around. I don't have a shortage of 300WM brass, so I can afford to wait.
Grafs has it in bulk so if you have someone to split not so bad hit on wallet
Mine came today. Kudos to Graf & Sons for their packaging. The two full ammo boxes were placed in a box-in a box- in a box, kinda like Nesting Dolls. I'll get around to inspection measurements this week, but they all do seem to have been annealed properly and have proper flash holes without burrs. And of course no dented necks !!!!
When compared with other new brands SIG, AMMO Inc, GFL, Nosler, JAG, Barnes, Rem, Win, one can definitely see the difference in length to shoulder.
Bob Wright
Well-Known Member
Hoping that Peterson carries this over to 7RM and other 375H&H parents. I know my 7RM fireforms @ .019 after a few loads. The Nosler brass just can't be pushed too hard due to pocket life.
All 300 Win Mag brass can headspace off the shoulder, after the 1st firing, if you resize correctly.
Run the Peterson long brass through a sizing die wrong (or, correctly, depending on your perspective) and it'll be spacing off the belt, just like regular 300 Win brass.
We need someone to make 300 Win Long dies ormost a lot of people that buy this brass are going to mess it up and make it 300 Win "short" brass.
Run the Peterson long brass through a sizing die wrong (or, correctly, depending on your perspective) and it'll be spacing off the belt, just like regular 300 Win brass.
We need someone to make 300 Win Long dies or
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Bob Wright
Well-Known Member
I don't think it's a problem for experienced handloaders.
Dies are also available custom to fully fire formed brass from most die manufacturers. But regular dies work pretty well for me.
For the guy who smashes his Peterson long brass back to SAAMI ammo datum length, Peterson would be glad to sell him more.
I agree 100%. I'm not so sure it's obvious to everyone this brass is only special for the 1st firing. Someone needed to point it out. Admittedly, I'm being "that guy" right now.
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Bob Wright
Well-Known Member
I was curious about this subject, so I contacted Peterson Cartridge Company and here is their response.
My question to them
What dies do you use for resizing and how do I keep from over sizing my new brass. I. E. Making it like the
standard brass?
> Thank you for reaching out to us with your inquiry. You use the regular .300 Win Mag dies. You are not going to over size our .300 Win Mag Long cases. The dies are designed to give minimal shoulder bump on the .300 Win Mag cases. They will never be able to size them down to a standard unfired .300 Win Mag case. Please let me know if you have any other questions or concerns.
>
> Ben Preston
> Retail Manage
Peterson Cartridge Company
> www.petersoncartridge.com
> Office: (724) 940-7552 Ext. 205
> Cell: (724) 967-797
