So target is ShootSteel 3/8 AR 550 its a 12x20 inch sliloette.... 10 hits 100yds Winchester white box M193 circled in red fired from BCM Recce 18in barrel, the green circle is 7.62 x 39 Wolf fired from standard Yugo SKS, 100 yds as well.

Is this normal wear and tear for AR 550 steel at 100 yds. My expectation was to see no divots in the steel. The 5.56 divots are perfect little bb diameter.

The following is from my experience only. I'm sure better informed posts will follow.

That looks pretty standard. As you reduce range from 100 yards the damage will increase exponentially. A little shorter in range and you will have craters. By 150, you damage will be almost non-existent. Velocity destroys your steel more than anything else. I do not shoot any rifle (except pistol caliber) at steel less than 100 yards.

I am REALLY conservative when it comes to shooting steel. Targets I use for handguns at closer range are separate from those used for rifles. The flatter the surface of the steel the less likely anything comes back at you.

Thanks Chubbs...glad the divots are "normal", was short on time today so next week, I'll go out to 150 yds. test my M193 and some other brands I have, got a lot of PMC Bronze and Xtac...supposed to be pretty mid 5.56 loadings so I'm expecting no impact to the steel. Clearly the Winchester m193 is as advertised at 3100 fps+ And yes...my pistol targets are pistol only, they are pristine, I understand its critical for the pistol targets at 25 yds to be divot free, to avoid any back splash.

Chubbs103 is spot on.

That's exactly how our 100 yd rifle steel looks. We never shoot at our rifle steel closer than 100, and never shoot rifles at our pistol steel.

I recall reading that AR550 won't pit at 150 yds and AR500 is good at 200 but can't recall which target manufacturer said that.

I’m in agreement with the others that the divots are normal.

I don’t shoot steel with a high velocity (3000 fps or greater muzzle velocity) rifle at ranges less than 100 yards.

I also generally only use 1/2” steel for rifle targets and reserve 3/8” steel for handguns. I found that 3/8” steel plate has a tendency to slowly bend, and has to be turned around to bend it back, but then it tends to crack. I’ve broken 3/8” plate but not 1/2” plate.

I also used to shoot in the frozen north and I found that in sub zero temps plates had a bad habit of shattering with M193 at 100 yards.

angling the plate will reduce the impact damage

Also, don't shoot your steel targets with a 375 H&H at 80 yards, even with lightly constructed bullets. They don't like that.

I do believe that some of the folks who make steel targets give velocity/safe range suggestions. Pay attention to their advice. IIRC, birdhunter6 has it right "I recall reading that AR550 won't pit at 150 yds and AR500 is good at 200 but can't recall which target manufacturer said that." The outfit I used to buy steel from sold out, the guy retired
The vendor who supplied our reactive targets at work also warned against continued use of targets with craters/dimples. While the flat plate is supposed to fragment the bullet, the crater/dimple can redirect fragments back toward the shooter(s).

Damage to metal reactive targets is why they developed frangible bullets. However, some of the atomized copper bullets have been known to fragment during the M4/clone feed cycle. Barnes developed a bullet they call the Reduced Ricochet Limited Penetration (RRLP) to solve that problem. It has a jacket and a core made of atomized copper in some binder. Feeds without issue, doesn't damage steel, probably comes apart when contacting hard surfaces and, surprisingly, has somewhat better tissue penetration than M193. I expect someone loads it (under contract?), available-but not cheaply-for reloading.