Monday, April 15, 2013

Not What I Expected...

So, I mentioned going shooting yesterday with friend, commenter, and all-around mensch Brad_in_MA yesterday. He's been itching to try out the Conspirator AR-15, and his range has both 100 and 200 yard stations for shooting steel with rifles. This was surely a match that would go well, right? The 200 yard station has its own dedicated 18" steel plate suitable for everything up to .338 Lapua Magnum (previous outings have seen it survive hits from a .325 Winchester SSM). The 100 yard station has hooks available, so I strung up my 10" steel plate from AR500.

We shot the 10" plate with the Conspirator (.223 Remington), several .22LR rifles and a handgun, 9mm out of a carbine, and .357 Magnum out of a rifle and handgun. At the end of the day, we were shocked to see this:


Four holes punched clean through. Decent grouping, too, for 100 yards... Now, I've hit this with 9mm and .223 Remington before - the .223 Remington leaves the tiniest hint of a dimple; 9mm doesn't even leave that much (same for .45 ACP and .38 Special). The only new caliber is the .357 Magnum - which was fired out of the Rossi model 92 lever action rifle with 24" barrel.

Now, when you hear about a round going through a steel plate, it's usually because a rifle round was shot at a plate meant for handgun ammunition. Naturally, my first thought was that the holes were made by the .223 Remington out of the Conspirator; however a closer look revealed otherwise:


Yeah, that hole is WAY too big for .223 Remington. We deduced that the holes had to have been made by the .357 Magnum out of the Rossi, since both the 9mm out of the Kel-Tec SUB2000 and the .223 Remington hit the plate far more than 4 times. The Rossi only ran a total of 7 rounds through it, five from me and two from Brad, so it's far more likely to have been the culprit.

Isn't that weird? .357 Magnum out of a rifle had enough power to get through a 3/8" thick steel plate that easily stopped a .223 Remington? I wouldn't have thought it possible, but the proof is in the plate, so to speak. Or through the plate, more accurately...

Other highlights from the day:
  • Hitting the 10" steel plate 5 out of 10 times at 100 yards with the Ruger 22/45.
  • Hitting the 10" steel plate (once) at 100 yards with the Smith & Wesson model 13.
  • Hitting the 18" steel plate at 200 yards 19 out of 20 times with the Conspirator (and I suspect that the 20th time was a hit dead amidships that didn't make enough noise to hear).
  • The Conspirator ran like an absolute top. I think we put ~ 80 rounds of lower end .223 Remington through it without the slightest hiccup.
  • Running the 15 yard plate rack and dueling tree with the Kel-Tec SUB2000 like a boss. Six horizontal plates on the rack and six vertical plates on the tree hit in very rapid succession. The SUB2000 has impressed the hell out of me.
And in any case, it was a day spent lobbing lead downrange with a good friend - what more can you ask for?

That is all.

15 comments:

Julie said...

Sounds like it was a great day!

Papafah said...

Was anyone else shooting there? I would guess someone else was shooting your steel.

ZerCool said...

Those actually do look like .223 holes to me - very similar to what I've got in one of my plates from an AR. A couple possibilities come to mind. First, like papafah - was someone else shooting your plate? Second, did you perhaps have some green-tip 109 mixed in?

Jay G said...

Papafah, if anyone else had been on the range that would have been my very first guess. We were the only shooters on the rifle range the entire time.

ZerCool, the picture doesn't really show it that well, but the holes are significally larger than .223. A .223 round will fit into the hole up to the shoulder.

LC Scotty said...

I've been eying up one of the Rossi 92/Marlin/winchester etc. in .357 for the house. How do they do with JHP (Gold Dot or Critical Defense)?

Tierlieb said...

The chance that the holes can be blamed on some .357 Mag are much smaller than .223 Rem being the culprit: Lower e0, much lower e100, worse sectional density.

The hole size does not need to correspond with the bullet diameter, as long as it is bigger. If the burr shown on the picture is actually on the front of the plate, not on the back, you can assume that the steel behaved nearly liquid during deformation. If you're good with a caliper, you can measure whether this is actually a cylindrical whole, which I doubt.

As an explanation, I'd go for either some steel core ammo mixed in with the other (does happen) or at least a really hard lead core combined with a copper jacket that was way thicker than standard (does happen a lot). Maybe some problem with the hardening of the plate. Probably both. The latter theory can be tested rather easily with a standard Rockwell-C-scale hardness tester. I would assume the maker of the plate might be interested, too, so you can ask them for help.

As for the target: 3/8" are quite a lot, but keep in mind that even really expensive maraging steel plates need 9mm to 6mm to be rated as resistant to armor piercing 5.56x45. And AR500 is much cheaper and, I assume, therefore produced with a lot more variation.

Mopar said...

I'm agreeing with ZerCool on this. I just can's see that .357 JFP penetrating the plate like that. That soft, flat bullet should have splattered on contact (like you see in places in the first picture).

Geodkyt said...

Both M193, M855, and true (i.e., not downloaded like the British) SS109 have far more steel plate penetration than people assume -- especially compared to civilian .223, oddball 5.56 milsurp, and a lot of "made for civilian market" 5.56mm.

What loads were you shooting in 5.56mm?

SgtRed said...

Those holes look exactly like SS109 holes. I argued once that there was no way my rounds were punching .30 cal holes in the Navy's steel. I was wrong.

Geodkyt said...

Oh, and Tierlieb's deformation theory is dead on for what the pic shows me and what I would expect for a high velocity 5.56mm US ball hit.

Bubblehead Les. said...

Going with the .223 Remington. Because you said you were also using the Keltec, that would mean you were sending (basically) the same Bullet (.355/.357) through the same length barrel within a couple of hundred feet of each other, yet if it was the .357, there should be a LOT more holes in the plate because of the 9mm.

I'd take the time to inventory and sort your Ammo. After all, you don't want to be caught with that Dreaded "Cop Killing Armor Piercing Police Vest Hole Making Ammunition of Mass Destruction," especially up there with your Anti-Gun Laws.

Old NFO said...

I'd say that plate is NOT AR500... And good possibility that was steel core penetrator ammo from a 5.56...

Brad_in_MA said...

@all -- We used 3 types of civvie 223, 55 grain ammo on the plate: Remington, Federal American Eagle, and PMC Bronze. Not sure which of the three were the culprit.

@Tierlieb - Yes, the pic is the front of the plate. Are you saying the impact energy of the four rounds that created the four holes essentially "vaporized" the steel, allowing the rounds to pass through? And that the residual heat of the impact caused the holes to be larger in diameter than .223 inches? I know in welding / metal cutting, one has to take care to make sure the edges of the weld/cut don't degrade the hardness of the material. That's why laser cutting is so useful -- it minimizes damage at the cutting edges.

@Les, in spite of all the nuttiness, MA has very little in the way of ammunition restrictions. Lots of clubs have their own stuff. Prohibitions on steel-core fodder are common.

Anonymous said...

Most definitely NOT .357. The holes created by steel being vaporized by high energy loads are always much larger than the actual round. 7mm holes are close to .50 in size.

And something significantly reduced that AR500 hardness if ANY of those rounds penetrated, including 109, 855, etc.

None of those should penetrate AR500 under normal circumstances.

BUT...no way it was the .357!

Geodkyt said...

IIRC, Fed American Eagle is basically "M193 for the civilian market" (never intended for possible DOD purchase, as opposed to the XM193 stuff that is simply M193 production overruns without the primer sealant).

AFAIK, the PMC Bronze is also pretty near M193 spec, and would perform on steel about like M193.