Optimal barrel length

[LRRPF52]

Personally, I've settled on a 14.5" pin and weld as my ideal general length. It's very short and very light, but not so short as the 12" and retains some nice velocity. With a 14.5", firing the common 123gr Hornady SST general purpose hunting ammo, you get over 1000 ft-lb impact energy at over 200 yards. with Supersonic flight still at 700 yards. That's pretty good for a very light handy barrel. 16" will go even longer, and is more common.

What mv are you getting with 123gr SST factory, and your hand loads from 14.5”?

I haven’t seen much difference between 12” and 14.5”. This is also true with 5.56 NATO.