What would be considered quality HD ammo in 223/556? Assuming BTHP? Those same manufacturers? Plus the usuals federal, hornady, etc?
Softpoint is your best bet. Some HP ammo as well especially in a solid copper projectile. Your usual suspects of Winchester, Federal and Hornady along with Black Hills, Speer and Barnes make good "defensive" ammo.
Avoid the softpoints or JHP in Russian ammo for "defensive" work. They use a steel jacket and you don't get reliable expansion. it still pokes holes, but you aren't going to get the effects you desire.
M193 is a good "backup" defensive ammo. It's designed to fragment and cause a greater wounding potential. If all else fails, it still works just fine as a "can't get anything better" ammo.
Generally reputable brands that shouldn't give you any problems:
Federal, Winchester, Hornady, IMI, Prvi Partizan, RUAG/Geco/Ammotech (if you can find it), PMC, Black Hills, Remington (when they come back), Wolf, Brown/Silver/Gold Bear, American Eagle (made by Federal), Tulammo (though generally a bit underpowered), Barnaul, Lake City (actually made by Federal), Sellier Bellot, Magtech, Fiocchi, generally any surplus from a NATO (minus Greece) or "First World" nation is good to go.
Russian ammo tends to be steel cased. Don't buy into the hype it's "bad" for your carbine. It's dirty and not what we would consider accurate ammo, but it shoots okay and as long as you have a good cleaning schedule, it'll be fine. Good "training" ammo for a decent price.
Monarch ammo is made in Russia by Barnaul under contract for Academy. Haven't heard anything good or bad about it. Fired maybe 20 rounds once and it went bang every time.
Can't speak to Armscorp, Aguila or Red Army ammo, so won't opine. I have used Aguila .22 LR ammo and it works, so it
should be okay in the .223/5.56 variety.
Brands to avoid:
Any surplus from a nation not NATO or "First world." I.E. Malaysian surplus. Basically, use the "would I drink the tap water in this nation?" standard as "would I shoot their ammo?" test. Doesn't always work (Aguila for example) but a good rule of thumb for surplus.
Reloads that don't come from a reputable source. I.E. Reloads you find at gun shows. Nothing says "I want to blow up my carbine!" more than picking up a hundred rounds from Billy Bob's Live Bait and Basement Reloading Shop in a Ziploc baggie at the gun show and find he's used pistol powder in a rifle case.
I generally avoid reloads period unless it's, again, a reputable source like Black Hills.
Ammo you can't verify how it was stored. If it wasn't in a sealed can, you have no idea whether or not it was stored properly.