what precautions, if any, do you have for someone who wants to shoot 175 gr SMK commercial ammo through a commercially-produced M14-styled, semi-auto rifle? </div></div>
First thing, you want to remember is to get something, you have to give up something. Other than that, it is how much money you want to spend, to drive a 14 to the target your after. As for a "Factory" loaded 175smk you don't have much to worry about, even though it's more pressure, than normal NATO working pressure. I doubt you will get her combat hot, where port pressure really jumps. The M14 was "Made" to do many tasks. Some of those tasks were never on the drawing board when she went into production, but she adapted to some tasks w/o issue, not so well to others. Quality training, and a stalwart operator, made up for her short comings everytime.
I've a rack gun that will drive my 175smk handloads into a 1-1.5 moa group with iron sights, depending on my day.