Last night I was occupied with a 9,3x62 Mauser and my thoughts wandered off into wildcat territory. I dug up an old Gun Digest from the 1980s where Ken Waters had a story about a rifle of his, a Westley Richards .318 that produced the sharpest 90 degree shoulders - the barrel had a marking Square Shoulder patent Nr something.
It seems WR experimented with shoulder angles in the early 1900? Does anyone have information on this?
My 30-06 AI produces no loss or gain in velocity when forming brass with factory loads. So a sharp shoulder is of no use if the round is standard (right?) but then a Sq.shoulder chamber could be used both with standard and formed; with some increase in velocity with the formed round.

The gain in a square shouldered 9,3x62 would probably be marginal, but I have a theory that the high energy Vihtavuori N550 and N540 likes bottleneck rounds and just might do something special.

But then, if WR tried it and it was not adopted, why bother?
Anyone read something about this, or have experience with old Sq.shoulders?

Besides, Square Shoulder sounds more exciting than Ackley Improved, with all due respect to P.O. Ackley.

Boha

Boha

Many wildcatters have experimented with shoulder angles as a way to increase efficiency, accuracy, velocity, etc. Whether or not it really makes any difference beyond a certain point is open to arguement. I prefer to stay at 40 dgrees or less. One disadvantage to steeper angles is that it is very difficult if not impossible to "bump" or push the shoulder back to allow for easier chambering of fired cases. This is a problem even with the Ackley 40 degree shoulder and many times the empty case has to be discarded. One wildcatter who has experimented with the sharper shoulders is J. D. Jones of SSK Industries. He has several wildcats with a 60 degree shoulder and I assume they work OK. I don't know of a web site or e mail address for J.D. but his phone number is 740-264-0176. He is always eager to talk with fellow experimenters.

Good Luck, Ray

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Thanks Alf. But then, not being milled, but fireformed and having the sharper angle, a square shouldered case today would have some effect, wouldn�t it.

What caused a headspace problem? The 318 looks pretty ok to me headspace-wise.

Boha

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