Re: M118 175g vs 175 match king
NRA testing in the 1980s sorta de-bunked the idea that M118/M72 bullets were not accurate enough for over-the-course bullseye shooting.
Out of bolt guns, they were getting .75 yo 1.0 MOA all the time.
However, their testing of Service Rifle loads also showed that SMKs fired from the same boltguns were running .5 MOA to .75.
Make your choice according to your own standards. If you choose to use M118s, I suggest you sort them by weight like my Dad did in the M72 days, and also sort by base appearance as someone more recently has recommended.
If you're shooting an M14 type that gets 1.0 MOA with SMKs, don't bother with M118s unless it's for practice. They will do 1.5 MOA quite reliably IME, but sometimes will throw a 2.0 MOA group. Okay for that 2 MOA 10-ring, but most of us want more room for shooter error.