Exit holes from my 30-06 were 2 inches across and maybe a bit bigger. I am running the 120 grain Speer SPBT in my 257 Roberts and it is a quick killer.
Speer 120 is what I used in my 77V 25-06 on 20 something caribou over 3 years. Handloads.
Same result as yours. The OP SST results are surprising, considering my experience with 150 SST's in the 30 '06, on caribou, also mirroring your results.
I believe SST's are designed for expansion at longer ranges, lower velocities? I used Hornady Super Performance factory loads at about 3100. The GMX didn't produce as big holes under 300 yards, but were just as effective as the SST. About 8" difference in POI at 300 yards, the GMX going high and right.
Who needs premiums???
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If I still had a .25-06, I'd likely use Speer 120's or something close to it in Corelokt or Interbond for handloads at closer ranges. Maybe even a mono.
