Peterson 7mm rem mag "long" version

[sdupontjr]

I see peterson offers a long version in 7mag. Suppose to help minimize case stretch on 1st firing. Anyone using this and if so, any pros / cons?

 

[muzz]

I don’t understand what the long version is. Anyone enlighten me?

 

[WeiserBucks]

I don’t understand what the long version is. Anyone enlighten me?

The base to shoulder measurement is longer than standard brass to allow the handloader to bump the shoulder back a desired amount prior to the 1st firing and therefor minimizing case stretch on the 1st firing.

Belted magnum brass has always been notoriously short and stretches a significant amount opon the 1st firing and shortens the useful lifespan of the brass. Peterson long brass is one way to avoid that issue.

 

[Mike D Texas]

It’s brass for sale but gives a description of the long concept.

Peterson 7mm Remington Mag "Long" Brass 50 count (New)

Peterson 7mm RM Brass 50 count

www.submoashooting.com

Sent from my iPhone using Tapatalk Pro

 

[IALoder]

I just started loading with some of the 7mm RM Long brass. Shoulder bump in the package was .004-.005 from what my once fired measurement was. Which is WAY less than any of the factory loads I measured. Brass is SUPER consistent weight wise, and is definitely top quality.

 

[sdupontjr]

I just started loading with some of the 7mm RM Long brass. Shoulder bump in the package was .004-.005 from what my once fired measurement was. Which is WAY less than any of the factory loads I measured. Brass is SUPER consistent weight wise, and is definitely top quality.

Very nice. Was looking for some real world experience with it.

 

[Gargoyle]

So you shoot a regular one time and it does it stretch one time, then you bump it .002 from there. That initial stretch of the case dooms it's life?

 

[sdupontjr]

I've noticed that in both my 7 mags, tikka and browning Abolt, it took 2 firing to fully stretch and fill chamber. So my thinking is that cant ve good for case life. Thus peterson made 300 wm brass long and folks really liked it. It wasnt until recently that started making the 7 mag long version. So any additional length should help from what I've read.

 

[WeiserBucks]

So you shoot a regular one time and it does it stretch one time, then you bump it .002 from there. That initial stretch of the case dooms it's life?

Belted mags headspace off the belt vs the shoulder and will likely stretch .020"-.030" before they're fully formed. That initial stretch thins the brass just ahead of the belt and can lead to premature case head separation.

 

[coast range]

Would loading longer coal help? Maybe they wouldn’t fit in your mag but just off the lands.

Would it be worth it to gain some extra firings in the long run? Or dumb idea??


Sent from my iPhone using Tapatalk

 

[Gargoyle]

Belted mags headspace off the belt vs the shoulder and will likely stretch .020"-.030" before they're fully formed. That initial stretch thins the brass just ahead of the belt and can lead to premature case head separation.

I think mine went .017 first time. I haven't noticed anything of detriment yet. I do have a borescope and can check that area. So cool!

 

[WeiserBucks]

I think mine went .017 first time. I haven't noticed anything of detriment yet. I do have a borescope and can check that area. So cool!

It's worth keeping an eye on as your brass gets fired and sized repeatedly. A case head separation is no fun.