So, I finally pulled apart my remington core-lokt factory 150 psp that is the only round i can find working perfectly in my 7400 :banghead: , and weighed their powder. It was 53.3 grains of some large black shiny grain stuff that looked like IMR 4138 maybe? Anyway, I've gotten core lokt bullets to try to replicate the load and hopefully use the powder on some other bullets like the hornady 154 grain, but I would like to identify this powder. The online Hodgdon resource doesn't show 53.3 grains of anything, or even close. IMR 4350 is listed in Sierra's manual as "the accuracy load" at 53 grains (according to the interwebz) but, I've never seen the powder so; it does it look like that?