The weight is in the barrel needed to stabilize flight. 300blk can stabilize a heavy 7.62 bullet faster in a shorter package.
Agreed very different tools.
Can you slow down .308 to sub, yes. But can a traditional .308 rifle accurately shoot it, no. A 1:12 or 1:10 twist is not ideal for a slow-moving 220gr projectile. But a 1:8 twist can, and also do it with less barrel.
#1 advantage of the bolt vrs. gas gun shooting suppressed is noise. #2 we can slow the bullet down to any speed we want where it still leaves the barrel and the bolt will always cycle.
OP: Dont forget the B&T SPR300. Two stamp gun but designed from the ground up to be as quite as balisticly posible. Over the barrel purpouse built B&T suppressor. (H&K style) Whole package fits in a small bag. Folding stock and the suppressor comes off.
I can tell you how it shoots in a solid yr or so as the two form 4s soak with the ATF. Bought it 4 months ago, stamps went in two months ago and still have not been cashed.
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