Western powder lists .20 Tac loads, which although nearly identical, I know it's not exactly the same. The highest velocity they got with the 40 Vmax at 62,980 psi is 3835 with A2520. They are using a 24" barrel. Hodgdon lists H4895 as a compressed max load of 27.7 grains in a .204 case which is a larger case. According to a friend in a major ballistics lab that actually psi tests these loads, many of these safe in my gun loads are way north of 70,000 psi. Just food for thought. Chances are if anyone is actually seeing 4000 fps, it is way beyond 63kpsi. Western powder also lists a 63kpsi .20 BR load with a 40 Vmax. The highest velocity they got was 4035fps with A2520. I know many on other forums think that the loading manuals are written by lawyers, but they do actually pressure test the loads and the max loads they list are what is saami listed for the highest psi for the round they are loading, using the brass, primer, bullet and powder in their test barrel. There are a handful of guys on the Accurate Shooter site that seem to always get 2-300 fps faster than book loads that are "safe in their guns", that one needs to take with a block of salt.
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