Winter coming on must be playing tricks with 'em. Seriously, I hadn't messed with any of mine in quite a while, certainly not in the Spring-Summer-Fall months. Got out for a little funshoot the other day and observed some wandering, uncalled flyers, with two of my Garands. Three or 4 rounds in a 10 ring cloverleaf, the rest of the clip out in the 8 ring boonies. Gas plugs tight, duhhhh, checked front sights for tightness. Yeowww, back & forth rocking of the gas cyl's, just slight but rocking nonetheless. An old friend and great 'smith with old milsurp rifles & pistols, Robert Joseph of Austin ,TX (pardon shameless plug), then taught me a new trick about peening these barrel splines. Blade-peening, 3 or 4 strikes across each spline. Your barrel's splines have probably been roll-peened at some point in time. The blade-peening compensates for a spline that isn't impressed any more by a 1/8" ball bearing or a 1/4" socket. Gas cyl's went back on tight as all git-out, locks bottomed out close to perfect, gas plugs tightened up like a piece of cake, brought everything home. Shots won't wander now. Life is good.