14 February 2005, 18:17
jeffeossopressure to seal case
let's say in 458 win.. what pressure is a good rule of thumb for the necks to stop being smoked?
IIRC, that's generally 38-40k psi... but I wanted to double check
jeffe
14 February 2005, 18:30
b beyerI do not know about a streight case like a .458 but I shoot some pretty high pressure loads in bench rest shooting, and do not remember any case not having residue on it. If I had to guess, I would say that the point that you stop smoking necks would be one grain more powder then it takes to blow up your gun.
14 February 2005, 18:45
jeffeossoBeyer,
thanks for the post... on straight necks and nitro express rounds, we are talking a thick black smoke, not smudge...
jeffe
14 February 2005, 18:47
CDHI get residue on necks with full house 60k+ loads.
I get resudue on shoulders and bodies of cases and figure that is when I am not getting a seal, and stop reducing loads accodingly. That usually happens somewhere in the 2/3-3/4 of max powder charge ('06 and WSM based calibers). What PSI that converts to is only a guess...
14 February 2005, 19:10
DutchIt depends on the case thickness and the burn rate of the powder.
Using Quickload estimates, Lapua brass seals at something like 40 to 45,000 PSI in my gun.
My 223WSSM with heavy bullets and Magnum seals rather close to maximum loads (55,000psi, estimated), with the BR-2 primer. Using the 210 seals those loads two grains earlier. FWIW, Dutch.