I been case making for 45 years and at first tried
shorter and fatter cases, never got what speed I thought we should, then
I started lengthening them out, and found a balance of
length of powder space to diameter of the powder space on
necked cases, that got closer to the ideal. Like my 585 a straight case can get over
14,000 ft lbs, at 70,000 psi, and as we neck it down the energy we can get at same
pressure, same weight powder, drops at every caliber going down,
so that as a 375 energy is about 9500 ft lbs. This is with same length case.
If case is shortened and made fatter to hold same powder at same
pressure, speed/energy drops more. IE if I could get a 375 HE with .300"
more length be better yet as we here can find powders to work...
When I made my long 458 many years ago it was straight, real long,
and 458 wildcat made from shorter blown out Jeffrey couldn't keep up
even though held same powder.. Ed
shorter and fatter cases, never got what speed I thought we should, then
I started lengthening them out, and found a balance of
length of powder space to diameter of the powder space on
necked cases, that got closer to the ideal. Like my 585 a straight case can get over
14,000 ft lbs, at 70,000 psi, and as we neck it down the energy we can get at same
pressure, same weight powder, drops at every caliber going down,
so that as a 375 energy is about 9500 ft lbs. This is with same length case.
If case is shortened and made fatter to hold same powder at same
pressure, speed/energy drops more. IE if I could get a 375 HE with .300"
more length be better yet as we here can find powders to work...
When I made my long 458 many years ago it was straight, real long,
and 458 wildcat made from shorter blown out Jeffrey couldn't keep up
even though held same powder.. Ed