I am not trying to be disrespectful,just talking straight.
If a guy wants to have fun blasting on a budget, a 10 rd SKS is hard to beat.
Feed it steel,brass,norinco,baurnal,wolf...it won't care and it is cheap ammo.
You have a nice AR. Instead of burning the barrel up,aim and squeeze each shot for accuracy,like it is a bolt gun that strokes itself.Make hits,not dust and noise.Think precision.Think of your ammo as part of that precision,not bangfodder.
Graf's might still have some Lake city primed brass semi-reasonable.There are folks who sell processed once fired brass.That is probably cheapest.
I would size it again as You don't know how worn their dies are.
Did you say you have 1-9 twist?.There are 62 gr boat tail fmj's Hornady makes a good one.I use 69 grain Sierra MatchKings or Nosler Comps.
There are other powders,but Varget works for me.
Our government thinking "Budget Minded" about ammo had a lot to do with the AR/M-16 troubles.
Learning to make good ammo is the best way to make your AR work.