Sounds like you are on the right track... My max load for my 260 Rem Match (CBI barrel) is 43 grains H4350 pushing the 143 ELD-X. I get 2745 FPS out of 25" barrel at 59 degrees. my seating depth is a bit longer because of my Match chamber. I'm guessing you 2.2 measurement is to the ogive? My COAL is 2.933 for my match chamber, but normal specs for 260 rem are 2.80 COAL.
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