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

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.
I'd like to get at least 25 new ones so I can start my load development on my new 300WM while it's still cold/cool outside.
 
I'd like to get at least 25 new ones so I can start my load development on my new 300WM while it's still cold/cool outside.
I tagged you in a recent post made by @Swamplord, as he developed info that they will be shipping some time in the next week or so.

I will be to talking to the guys at Peterson this week anyway about a different issue, so I'll try to update the members here on what I find out about their shipping schedule on the 300 Longs.

One way or another, we'll make sure you get that brass.
 
I tagged you in a recent post made by @Swamplord, as he developed info that they will be shipping some time in the next week or so.

I will be to talking to the guys at Peterson this week anyway about a different issue, so I'll try to update the members here on what I find out about their shipping schedule on the 300 Longs.

One way or another, we'll make sure you get that brass.
Thank you sir, that is really kind of you to say that.
 
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I tagged you in a recent post made by @Swamplord, as he developed info that they will be shipping some time in the next week or so.

I will be to talking to the guys at Peterson this week anyway about a different issue, so I'll try to update the members here on what I find out about their shipping schedule on the 300 Longs.

One way or another, we'll make sure you get that brass.
I talked to them last week and they told me to start looking in a month and then told me they are in production now and have a lot made that have to be inspected and then they'll start going out. Then he said to be on the safe side start looking in 2 weeks. I just looked and still none at Graf's. I hope putting in my wish list for some a couple of months ago put me in line to get some.
 
I guess I'm not seeing the reasoning behind the long brass, the issues have never been about the initial stretch on the first firing, it is the subsequent improper sizing and continual repeat of the movement on the first firing that kills the cases. The long cases will suffer the same exact or worse fate unless sizing practices are also modified.
 
From the case head area, which only pulls the amount of headspace which is set on the belt which should be .000-.004?
So just measured some cases above the belt as follows:

ADG Saami Unfired: 0.5050"
ADGSaami Fired: 0.5090"

Peterson Long Unfired: 0.5080"
Peterson Long Fired: 0.5090"

To Shoulder measurement:
ADG Saami unfired: 2.2615"
ADG Saami Fired: 2.2785"
Peterson Long unfired: 2.2750"
Peterson Long Fired: 2.2785"

Hope this helps.
 
The case shouldn't headspace off the belt, it doesn't need to. It should fit between the bolt face and the shoulder of the chamber like every other round. The belt is an anachronistic vestigial remnant that causes more problems (sizing, stretch) than it solves (none).
 
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