Peterson 300 WM - Std Length vs. Long - Initial Data & Impressions

[DoneNOut]

Let's not let this thread die! Especially since people are still asking the same questions before reading what badthirtyone so wonderfully prepared for the inquisitive minds present on LRH.

So, OP, and anyone else that's been running this brass, can we get a follow up? Please and thank you!

 

[Muddyboots]

Running the Long with 196HH @ 3150fps so nice load but not maxed out. Brass length grew 0.003 on 1x and has been steady thru 3X firings. Primer pockets just as tight as first load IMO. Annealed on 3rd firing which is my preference to anneal on odd firings. ( eg 1,3,5,7 etc) Just my preference, not right, not wrong, just my preference. Summarize: thrilled I bought 250 when it first came out before covid. Wow what a cost savings doing that then!

Peterson Long Brass Threads

 

[MW204]

This is Derek Peterson over at Peterson Cartridge. I want to say thank you for spending the time to collect all of this data. I am glad to see that our Ballistician Testing Data matches your findings. I will let our Ballistician, Stan, know that his work isn't going unnoticed. If you ever need anything, please feel free to reach out to our customer service line at 724-940-7552. Zack will be happy to help you out.

Derek, I've checked every website I can find and I cannot find your 300 WM Long brass anywhere, do you have any idea when it will be back in production?

 

[badthirtyone]

Derek, I've checked every website I can find and I cannot find your 300 WM Long brass anywhere, do you have any idea when it will be back in production?

MW204,

I don't know how often Derek Peterson checks this site. He has not posted since his first (and only) introductory message back when this thread was created.

I know that some stock of the 300 WM Longs have shown up occasionally, both here and on Graf's.

I know for certain that Peterson just completed a run of 7RM brass, that was sent to market a full month ahead of schedule, so hopefully they will be running the 300's within the next quarter. I'll update here if I develop any legitimate information on their production schedule for this and any other highly sought after brass.

 

[Longtine88]

Best brass for 300 WM IMO. I bet I have 700 pieces I use. Some on their 7th loading.

 

[MW204]

MW204,

I don't know how often Derek Peterson checks this site. He has not posted since his first (and only) introductory message back when this thread was created.

I know that some stock of the 300 WM Longs have shown up occasionally, both here and on Graf's.

I know for certain that Peterson just completed a run of 7RM brass, that was sent to market a full month ahead of schedule, so hopefully they will be running the 300's within the next quarter. I'll update here if I develop any legitimate information on their production schedule for this and any other highly sought after brass.

Thank you sir.

 

[Earnhardt]

How about using the 300wm Long brass in an auto loader?
(Browning BAR)
Any head spacing, or cycling problems any one has heard of?
Thanks

 

[Longtine88]

How about using the 300wm Long brass in an auto loader?
(Browning BAR)
Any head spacing, or cycling problems any one has heard of?
Thanks

Measure the fires cases from the rifle and see. I doubt you have enough but check and see

 

[Earnhardt]

Ok, so 300 WM long brass head spaces off of the shoulder?...
And old style 300 WM brass, space off of the magnum belt on the base?
Is this correct?

 

[Mike D Texas]

Ok, so 300 WM long brass head spaces off of the shoulder?...
And old style 300 WM brass, space off of the magnum belt on the base?
Is this correct?

It depends on your chamber but not likely, at least not until you fire it.

It does reduce case stretch though which is likely the main goal of it.

 

[MW204]

If anyone has at least 25 new Peterson 300 wm longs they want to sell I'm all ears.

 

[Bucklowery]

Great job, Bad31

Thanks

Buck

 

[badthirtyone]

Great job, Bad31

Thanks

Buck

Thanks, brother. I enjoy the work, and that it gets appreciated!

 

[MW204]

Ok, so 300 WM long brass head spaces off of the shoulder?...
And old style 300 WM brass, space off of the magnum belt on the base?
Is this correct?

Pretty much, it's a lot closer to the shoulder, which stops the stretch at the belt.