Thread: 35* long neck 7 SAUM based on WSM

Hi guys. Hopefully there are a few wildcat gurus that can share a little insight. Two things I like on case is a long neck and 35* shoulder.

I have been playing around with a few 7mm options. I had a good hard look at the 7mm LRC that Pro Martusheff developed, but based on my current position I had to scrap that option. I have also been playing around with the 284 and Shehane, as well as the 7-270wsm and SAUM and a few improved options. After being through the custom wildcat route with a 300 NM Imp, I also considered the issues around custom dies etc and the potential solutions I formulated included the following.

- take a 7mm or 300 WSM die,
- shorten the die to a length that will allow you,
- to push (SLR) the shoulder on the 7 RSAUM back from 30* to 35* and create a longer neck,
- blow the taper a little out to the same shoulder dia as a WSM
- and potentially use the shorter WSM die to size your brass?
- set up a reamer that will allow for this.

If this works and even if one needs to use a small base die to start with, you will be able to get roughly the same capacity as the straight RSAUM, but I think the 35* would make it a little more efficient, have a little less case growth, have a longer neck and you wouldn’t potentially need custom dies, although you would only size the upper part of the case. The image below shows the straight RSAUM as well as the 35* option based on CIP specs and not SAAMI.

In an attempt to bridge the gap between theory and practice, what do you guys think?