Strange Bullet Markings

[Parks2055]

Figured I would stick with the reloading section as there is a lot of experience with ammunition here. I picked a new M&P 40 Pro 5". Tried some of my standard reloads (180gr Berry's with 4.7gr. W231) and was getting an odd marking around the bullet hole. I tried some factory federal 180gr. and same thing. The accuracy is still good, but does anyone know what is causing these rectangle marks around the hole?
Only thing I could think of was jacket separation except some of my reloads are platted and still same marking. Would that happen from a new tight barrel? The pictures are not too good - taken with my cell phone.
Any ideas would be appreciated.
Thanks,

 

[Certaindeaf]

It's probably just how the target backing and the way your target is affixed is affecting the face of the target. It's just a tear in the paper and not pre-expanded slugs flying through the air.

 

[bigfatdave]

looks like a target loosely attached to a beat-up or soft backer to me

nothing unusual

 

[blarby]

Heres the thing tho- those spatter targets don't mark unless something hits them from the front.

You can shoot them from the back, and you wont get spatter.

Can you get a better pic ?

Only reason I ask is that the rectangle has an unusually uncanny resemblance to the thickness of pistol rifling..... Im prolly stretching here, but you might be peeling your bullets at the rifling, and its staying attached to the slug.

 

[Parks2055]

Could be the target - although was attached to a new piece of corrugated I brought with me. I have shot thousands of rounds through these targets and never noticed markings like these until this new gun.
I will take my camera with me next trip to the range and get a better picture if it is still happening.
I did notice when cleaning the new pistol that the lands semmed very sharp - as they should be. Just wonder if it is something that will settle after a few hundred rounds of break in? or am I reading to much into this?
Thanks for the input.

 

[rcmodel]

Any chance you can shoot some into a soft earth backstop and recover some bullets to look at??

Thats what I would do if it was me.

rc

 

[Jaxondog]

I had some do the same thing with the "shoot n see" target's and the reason was I had them attached to a piece of OSB board that had got wet and started coming apart. Just my thought's.

 

[Parks2055]

Still Happening

Have not had the new M&P out to the range much lately, but did manage to go last night. I am still getting these weird markings around the bullet hole. Will post another picture - used fresh cardboard, plated berry's 180 gr (but did happed with Hornady jacketed as well) Not a hot load. It seems to me that it is a tight barrel and is causing the bullet to peel? Is this possible? Accuracy does not seem affected. Any ideas? I am just hpoing it is something that will go away as the new barrel breaks in.

 

[Old Shooter]

Whatever it is, identify it and patent it!

You could market it as the "Flying Frying Pan" ammunition or barrel modification or whatever.

I have a hard time seeing how the rifling could strip the bullets consistently in that manner but that is what it seems to be doing.

 

[helotaxi]

Possible rough spot or burr in the barrel?

 

[LoonWulf]

Im inclined to agree, maybe right at the muzzle. it really does look like its got a little thing hanging off lol. How far have you shot this gun at? I would think it would cause some in stability if it traveled more then a few yards.

 

[rcmodel]

Have you tried post #6 yet??

rc

 

[Parks2055]

Hey RC - I meant to mention I shoot at an indoor range in Canada.
No opportunity to shoot outdoors and recover a bullet.
That would be best bet to see what is happening.
Maybe shoot into telephone book or something like that or would that just mangle it?
I scrubbed barrel with a Tornado (wire brush) and up to the range for a quick thirty rounds. No markings this time. Will try again with more time and ammo.
Still getting an occasional feed problem. Seems to be getting better as I increase COL.
Up to 1.140 now. Anybody have recommendation for COL on M&P 40 Pro 5"?
I have read a couple of forums with similar issue on this gun where the round gets stuck on the feed ramp. They needed to increase COL for consistant feeding.

 

[RustHunter87]

sure looks like ripped paper to me, shoot some targets with plywood backing, or just shoot some plywood, i bet you get round holes

 

[98Redline]

There is something definitely hanging off of the bullet. The rectangular marks in the cardboard show a gray border around them the same as the nose of the bullet. The spatter targets show in impact in the area of the rectangular mark.

It looks to me like jacket separation (or at least one petal of the jacket peeling back as it exits the muzzle). There is a possibility that it is not barrel/rifling related but more of a feed issue. If the nose of the bullet is getting snagged and dragged over something during the feed process it might be enough to cause the jacket to start to peel in that area on the way to the target.

Try loading a magazine and firing a few rounds. Try and determine when you start or stop getting this "hanging chad". Is it at the beginning of the mag, the middle or the end.

When you are getting the mark, reload a mag to the same level and fire a round or two then stop, clear the gun and inspect the bullet that is in the chamber. I'll bet you find the nose is damaged and the jacket is already peeling back.

 

[popper]

You didn't state if HP or TC bullets. If you are having feed problems, I agree with 98redline. It's hard to detect but if the mag lips aren't wide enough, the bullet rides low in the mag and will hit the feedramp low, dinging the nose. Doesn't take much at all for this problem. Double stack mag and single feedramp worsens the problem. Sharp corners on the feedramp may also be a problem.

 

[Sport45]

Stainless pins left in the case after cleaning?

 

[Jaxondog]

Stainless pins left in the case after cleaning?

Now that's a thought

 

[98Redline]

I would thing that if there were something "extra" in the case that was in fact pushed out by the powder charge, it either wouldn't hit the paper at all or not be nearly that close to the bullet impact.

 

[noylj]

Look up the word facetious.

Very strange. That is simply too sharp a cut to not be a bullet failure.

If you are shooting at less than 15 yards, the problem probably is not a problem--longer, and the bullet will start to yaw all over.

Do the rounds make a whistling noise going down range.

 

[sleepercaprice1]

It looks to me like the rifling is cutting the plated surface and leaving a "flap" of jacket hanging off the side of the bullet. I'll bet that the width of the slot next to the bullet hole will match the width of the rifling groove or land.