I bought some AR-Comp because I was running low on TAC, but I can’t find any good load data for AR-Comp at al. Alliant’s site has only max load with no pressure data given, and my Lyman book only has it for 1 bullet at the 69gr.

Does anyone have some experience loading with these? I’ll be loading w. Hornady 62gr FMJ and 75gr ELD using Federal 205M and CCI 450 primers.

I've only used it with standard 55gr fmj bullets.  25 grains is the charge I use.  Seems to work well, though.  I need to chrono my loads again, just to refresh my memory.  

You might check out Johnny's reloading bench, he has some vids with 5.56 loads/MK262 and AR-Comp

21.9gr worked very well for me with 77gr SMK.  They are a little slow at 2690fps but very tiny groups.

Hornady 223 Load data for 60-62gr

Hornady 5.56 NATO Load data 60-62gr

I had pretty good results using 24.2 grains under the 62gr fmj.

Haven’t used it yet with the 75gr. Hornady has AR-Comp loads for 75gr starting at 17.1 to 21.7

*standard reloading disclaimer* I have not fully worked up this load either.

Unless noted, my .223 loads use a #41 primer and WG cases.

With a 69gr SMK, my notes show 23gr at 2511fps from a 16", over a year ago. My dumbest didn't write down enviros, but 21gr - 2284fps, 21.5 - 2332, 22 - 2408, 22.5 - 2461fps.

Back in June, 80* 3150ft DA, 22.5gr gave me 2730fps (7sd, 15es, 3 shots) from a 22". Pressure was low, but I stopped shooting them as the rifle had too slow a twist and was printing 3" groups. Later, in mid July, my chrono failed (battery), but I shot them anyway at 50 yards from my 16" faxon barrel. Notes say 24.5gr was getting spicy in the pressure department, estimated MAX 25gr. With "great accuracy potential". We'll see what the chrono says, but it seems once I start seeing pressure signs in these loads, I've exceeded expected velocity.

Since you also use TAC, you may want to eventually try my pet load of a 55gr vmax with 25.6gr TAC. This load is around 100fps slow compared to 55gr factory ammo, but shoots lights out (close to 1 minute rested on a cinder block with hoodie) in my axis with single digit SD. Higher charges are safe, I've tested up to 26.7gr, but the load performs best at 25.6gr. If yall know where a fella can find more 55gr vmax in this market for a decent price, let me know. I only have 40rds of this load left and want to run it through my AR more. Most all testing of this load was out of my savage axis and I'm saving those 2 boxes worth for varmint hunting.

With a 55gr fmj, I've gone up to 26gr ARCOMP. Been using 26.5gr TAC, think I might need to tone it down to 26.2-26.3gr. I had some problems with it cycling a rifle, and I can spare 50fps for reloads. The 55gr fmj loads are out of mixed brass, range pickup fodder.

ETA: OP, keep an eye on grafs and midway. They get tac in stock quite often, lately they've only had 8lb jugs. I'd have grabbed another 16lbs off grafs the other day, but I honestly don't know where the hell I'd put it.

does anyone have load Hornady load data for 77 grain ? do they still have it on their site ?