I have a 71' Marlin .444 that I just found out has microgroove rifling.I Used 265 grain ammo last year hunting and really missed my mark even though I thought I hit it.I have recently heard that the microgroove barrels are designed for only 240 grain bullets,is this true?Could that 265 grain bullet have made me miss so bad?I am a pretty good shot so I was shocked when I made a gutshot when I was sure I made a vital shot.