I've had 17 AH , couple of 204's, 20 BR, 22 BR, couple of 6 BR's, 6 BRX, and lastly a ...223
Out to 400m my pick is 223 with 1:8 twist shooting sierra 69 TMK's
Problem with the 20 cal is your only shooting 40g projectile (unless you go to 1:7 or 8 twist and shoot the 55g Berger which havnt landed in NZ for a few yrs now) so its hard to see you misses. The heavier 69g usually kick up some dirt so you can adjust the second shot.
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