This might help, from ww....shootingtargets7.com/:
SHOOTING DISTANCE FOR AR500 STEEL TARGETS:
.22 Rim Fire, 9mm, .38 Spl, .44 Spl, .45acp – 8 yards
.357, .40 SW, .44 mag – 12 yards
Shotgun w/ lead bird shot – 12 yards
Shotgun w/ std velocity 00 buck – 20 yards
Shotgun w/ std velocity slug – 50 yards
.30-30 – 100 yards
.308, .30-06 – 150 yards
.223 – 200 yards
.270 Win – 200 yards
.22-250 – 300 yards
300 Win Mag – 400 yards
45-70 – 100 yards
When using a rifle the added distances are for the protection of the target and also the
safety of the shooter. Impact velocities approaching 3000 fps can cause slight pitting
and edge chipping of the target surface even with high quality AR500 steels.
It is interesting to note that the damage from these higher velocity impacts is primarily a
result of the intense heat created during the bullet strike and not the impact itself.
This intense heat creates a mini HAZ (Heat Affected Zone) that destroys the temper of the steel
and allows the damage to occur in this localized area. Observing the correct mounting
procedures (see tab 1) and observing the shooting distances posted above are two ways to
reduce or eliminate any damage to your targets.
A damaged and pitted target can become unsafe at ranges closer than 50 yards due to
in increased risk of ricochet or splatter concerns due to the uneven surfaces created.
Copper jacketed or plain lead targets are the only ammo types recommended.
Avoid the use of any steel shotgun slugs, pellets, steel core, green tip, xm-855, steel jacket or other armor piercing rounds.
Smart use will ensure you get the maximum life from your targets. With proper use AR500 targets can last
almost indefinitely.
See mounting (see tab 1) to ensure you practice the correct mounting practices.