More 5.56mm Penetration Issues

acmax2k · July 23, 2004, 02:37 PM

Hello All-

About a week ago I brought up the subject of 5.56mm penetration issues as it relates to home defense. Ironically, I've just had a lesson in what 5.56 will do when to WANT it to penetrate. Thought you might find this interesting.

This particular trip to the range turned into an inpromptu ballistics experiment. In short, my buddy had some 5.56 "AP" mixed in with his bag of loose ammo. Needless to say, 6 AP rounds found their way into one of his magazines. The results were impressive. The target is a steel 3/8 inch spinner cut from High Yield steel, and these targets are rated to sustain rifle fire. (3/8" high yield has the equivalent strength of 3/4" mild steel) 6 of 6 rounds deeply penetrated the front of the target, 5 of the 6 significantly dimpled the backside of the target. The deepest hole was 5/32" deep and the shallowest was roughly 3/32". He shot them at a distance of 50 yards. Check out attached pictures. Sorry for pic quality as I had to "save down" to get the file size small enough to post.

Much to my chagrin, he ventilated my rather expensive target. But, I've got to give credit where credit is due-that's a nice group for rapid fire offhand 50 yards.

Double Naught Spy · July 23, 2004, 03:09 PM

The results are not surprising, but also not hugely impressive. I have no idea what "High Yield" means in other sorts of hardness ratings, but have seen similar pitting results with 500 Brinnell (~52 Rockwell) rated 3/8" steel targets from MGM using 55 gr. XM193 ammo out of a 20" barrel AR15 at about 100 yards, but no deformation of the backing.

Steel rifle targets pit. That is a major reason it is suggested that steel rifle targets not be using as pistol targets shot at from pistol distances as the pits can cause ricochets back to the shooter.

Striker1 · July 23, 2004, 05:38 PM

Were these the green tip rounds? Interestingly enough, they might have penetrated completely at 75 or 100M.

acmax2k · July 23, 2004, 06:27 PM

DNS-

Clarification: Yes these are 500 Brinnel Plates. I Should have clarified.

These pics are not as high quality as I would like and don't really show the depth very well. I've attached one more pic that is indicative of what I usually get shooting standard 55 grain ball at around 100 yards from my AR. You'll note the dimpling you were talking about in the yellow plate's front but it is very shallow compared to the others penetrations in the red plate. The backside of the yellow plate is smooth and not disturbed. The difference is quite distinct.

Quartus · July 23, 2004, 07:21 PM

Quote:

6 of 6 rounds deeply penetrated the front of the target,

It would be more accurate to say they cratered the target.

acmax2k · July 23, 2004, 07:26 PM

You say tomato.....

Agreed. I will go along with cratered.

Actually, I believe my culprit that cratered my 500 Brinnel plate was Hirtenberger SS109 Green Tip.

July 23, 2004, 03:09 PM	#2
Double Naught Spy Senior Member Join Date: January 8, 2001 Location: Forestburg, Montague Cnty, TX Posts: 12,717	The results are not surprising, but also not hugely impressive. I have no idea what "High Yield" means in other sorts of hardness ratings, but have seen similar pitting results with 500 Brinnell (~52 Rockwell) rated 3/8" steel targets from MGM using 55 gr. XM193 ammo out of a 20" barrel AR15 at about 100 yards, but no deformation of the backing. Steel rifle targets pit. That is a major reason it is suggested that steel rifle targets not be using as pistol targets shot at from pistol distances as the pits can cause ricochets back to the shooter. __________________ "If you look through your scope and see your shoe, aim higher." -- said to me by my 11 year old daughter before going out for hogs 8/13/2011 My Hunting Videos https://www.youtube.com/user/HornHillRange

July 23, 2004, 05:38 PM	#3
Striker1 Senior Member Join Date: May 22, 2004 Location: TX Posts: 710	Were these the green tip rounds? Interestingly enough, they might have penetrated completely at 75 or 100M.

July 23, 2004, 07:26 PM	#6
acmax2k Junior Member Join Date: July 10, 2004 Location: Gulf Coast Posts: 13	You say tomato..... Agreed. I will go along with cratered. Actually, I believe my culprit that cratered my 500 Brinnel plate was Hirtenberger SS109 Green Tip.