IMO there are better choices available. I wouldn't
Use it at all in an m1 m1a or m14 ever but the gas system on an ar is not as sensitive to pressure duration. I would again, IMO maybe think about trying Winchester 748, Reloder 15, the new CFE 223 among others. R17 is a Little on the slow end of where I'd look to load but may be ok with heavy projectiles. YMMV
I forgot to mention I'll be shooting 62gr+. I just have a bunch of rl-17 laying around from an old project so I'd like to use it up. I'm ok with it not being optimal powder, because this will be plinking ammo. Once its used up I'll look for a more optimal powder for my AR.