Barrel damage after 100 rounds? M&P .40c

[The Wire Source]

Bought an M&P .40c this week, brand new, and shot the first 100 shots through it today. Noticed a lot of damage to the crown when I cleaned it after. I don't recall my M&P 9c ever looking like this after 2000 rounds. Do you consider this normal? I linked a few pictures and the ammunition used. Sorry for the fuzz in the pictures, my camera shows everything.

Federal Cartridge Independence Ammunition 5256, 40 S&W, Full Metal Jacket, 165 GR, 1130 fps, 50 Rd/b

 

[500 Magnum Nut]

Call S&W and tell them you need another barrel.

 

[handgunner356]

Hard to tell in the picture, sure it isn't powder buildup?

 

[The Wire Source]

No, it isn't powder buildup I don't think. I cleaned real well with a brush. It looks like bare metal. Oh, and I make sure to clean ONLY from breach to barrel tip, not the reverse. It was this way after firing the 100 rounds prior to any cleaning.

 

[Alk8944]

When enlarged it is obviously a build-up of some sort at the muzzle, not damage to the barrel base metal. It could be from the propellant or or could be lead deposition from microscopic amounts of lead being vaporized from the bullet base. Whichever, cleaning it will correct the perceived problem.

Did you use a bronze or nylon brush? Try a bronze brush of the next size, .44-.45, and you will probably have better luck.

 

[The Wire Source]

I have a bronze wire brush for .40-.45 that came in a kit, have used the smaller 9mm size for past guns. I'll see if I can get better pictures tomorrow. Up close, it looks like metal has scratched away from the crown. I tried again an hour ago, nothing is coming off.

 

[EAHILL]

Barrel Crown buildup

Hello, Wire Source.
First time shooting my 40c ( 50 rds. or so ) the crown on my barrel looked normal. Second time (100 rds.) I noticed the very thing you describe and your pics. show. With the aid of a magnifying loupe I determined it to be leading, even though the ammo. was fmj. and it was really solid.
I happened to have some Birchwood Casey Lead Remover and polishing cloth. I cut off pcs. the size I needed, ran some thru the bore and then went to the crown of bbl. with a pc. of wood to fit, angled it on crown and started to rub until it finally came off. The crown did not appear to have any damage. Looked like it was right out of the box.
Haven't been to the range since that, but am anxious to see what happens.
It may have been the particular lot of ammo I shot.
Will keep you posted.
Did you get your issue resolved? An curious to know what problem was.

 

[The Wire Source]

I believe it is some lead residue after all, first time I've seen it for multiple guns. Currently only own Rem Oil, but used that this afternoon and scrubbed with bronze brush. A tad bit did come off, but I had to scrub pretty hard in both directions. Really hoping I didn't damage the barrel in doing so because I know you're not suppose to start from barrel end. I also ordered a series of Hoppes cleaners to finish the job when they arrive. I should have had proper cleaners from the beginning.

 

[Tango 106]

It's the ammo

Just to let you know, the Independance line of ammunition for pistols is NOT true jacketed ammo. It is what years ago was called "copper wash" and was used to descibed copper "plated" 22 rimfire ammo. It is very thin. If you look at the Independance bullets, they are not a perfect smoth shape. They look kind of like a hand sculptuer lump of clay in the shape of a bullet, with copper painted over it. I have used this ammo and it is inexpensive and functioned very well with fine accuracy. As with anything, there is always a trade off. In this case a minimal jacket on the lead makes this affordable, but with hotter loads, leading is the risk. Change ammo and you won't see this kind of leading.

 

[The Wire Source]

^^ Thank you for the info. This was ammo bought at the range I went to. I never buy range ammo at a range store, but didn't have time to buy the usually ammo I buy in 9mm from another gun shop. They carry the same ammo in .40 also. I never have problems with their 9mm.

 

[EAHILL]

follow-up on 4/26 reply to Wire Source

Hello again.

Well, I kept having the problem and decided to take a look at the crown of the muzzle and found that where the barrel is chamfered, you could see the tool marks which looked like striations in the metal. Last weekend I went to the dealer I bought from and asked to see a new 40C from the display.....no striations and very finished looking. Dealer suggested I contact SW and relate the problem to them and ask for new barrel. I did, but was told I would have to send gun in for them to check out the barrel.
Sent me a label, and it was just picked up to go to Smith.
Aside from Winchester and Remington ammo. I have only used Federal Champion, and that is only time it will lead up. I may be proven wrong but I believe it is from unfinished crown and Federal FMJ.
Have any of you taken a close look at the crown of your barrels, and did you notice what I have described?
I know S&W will get the issue resolved. Will post outcome when I get it back.

 

[WR Moore]

I couldn't get any pictures to show up. There have been several similar threads on various websites. All the ones I can recall have been deposited lead from either jacketed rounds with exposed lead bases or plated bullets that were either poorly plated or driven too fast. The fact that your issue only seems to happen with one brand of ammunition make this more likely.

Minor machine marking on the crown does not touch the bullet. It generally simply indicates that the crown wasn't polished after machining.