Originally Posted By: Geo. Newbern
Originally Posted By: eightbore
George Newbern, Roster did not say anything like what you "said he said". Maybe you could reword your statement. He doesn't like any smokeless load in any composite barrel gun from what I can read. He has no idea what he is talking about.


Roster said about what I said he said regarding the necessity of low pressure, and he opined that higher pressures up 10,000 psi wouldn't hurt. He didn't say anything about my separate opinion regarding use of bismuth in damascus. That was on me...Geo


Many of us reduce pressure in our 2 3/4" reloads in order to shoot them in guns with 2 1/2" chambers. Based on information from Sherman Bell's "Finding Out for Myself" articles in Double Gun Journal. Given that the SAAMI standard service pressure for the 12ga is 11,500 psi, it's not a good idea to shoot most American factory ammo in foreign doubles or vintage American doubles if they didn't leave the factory with 2 3/4" chambers. But if you are working with a formula that puts you in the 8,000 psi range (easy to do with 12ga reloads) you won't come anywhere close to 10,000 psi even factoring in the increase (typically a few hundred psi) that results from the longer hull in the shorter chamber. You can also eliminate much of that pressure jump by having the forcing cones lengthened but leaving the chamber alone.