I hear mostly that 5.56 guns have a longer throat than 223? This helps alleviate the extra pressure? I have a Stevens 223 that even barely loading a 80 Vmax into a cartridge, I can't get it to touch the lands of my rifle. This gun currently shoots around 1 MOA with 55 Vmax over H335/CCI 450 primer and I'd like to make that tighter.... 1 in 9 twist so I'm not actually shooting the 80 grain....just used it for length testing at one time. Is it likely that I should have my head space adjusted? Or am I on the wrong planet in this thought process? Should I just get a go/no go gauge and check it? It seems that it can be a lot of work to shrink my groups. I realize that a better stock might help as well....but want to do the best I can with what I already have. Am I likely already there?