H&K USP .40 split steel case

SavJosh · September 13, 2013, 12:05 PM

Could be used as a warning against using steel cases, but I'm wondering if it also has something to do with my gun.

I've fired maybe 2000 rounds out of it in its 7 year life with me, maybe even less than that. I clean it after every shoot though, and take good care of it because its a really nice piece.

Last time I took it out to the range though, I used some TulAmmo .40S&W since it was the only thing on Walmart's shelves. I'd fired it through the gun before without issue, but this day a case got stuck in the chamber. Very stuck, had to disassemble, stick a pencil down the barrel and tap it out with the slide.

I picked up the case and it had a split down the length of the case, beginning maybe 3/8ths of an inch from the head and ending about 1/8th of an inch before the bevel at the bottom of the case. The split itself slightly thicker than a beard hair. Sorry I dont have pictures, but hopefully thats descriptive enough.

I ran a couple more TulAmmo (glutton for punishment) and about 1 out of 6 or 7 shots did this. A few weeks later I was finally able to get some Federal brass ammo from Walmart and I took it out. The brass isnt splitting, but I am noticing an ever so slight bulge at the bottom. Placing them back into the barrel they slide right in and out so I'm just not sure if it was a bad batch of crap steel ammo or if my gun has a problem

Any advice is greatly appreciated.

PSP · September 13, 2013, 04:59 PM

deleted reply

James K · September 13, 2013, 06:31 PM

I don't know for sure about that ammo, but in some wartime ammo case splits resulted from hastily made powder that did not have all the acid washed out of it. When the ammo was stored horizontally, the acid seeped to the bottom (that is the side) of the case and ate partially through the case. When the round was fired, it split along the weakened line.

Jim

SavJosh · September 14, 2013, 12:28 AM

Well, this ammo was factory stuff, but being cheaper ammo than most everything else it may be a bad batch of some sort....

Then there's the possibility of it being older ammo, as this stuff had been sitting on my shelf for 6+ months though not laying horizontally.

I'm just hoping it was a bad batch but I'm wondering if it may be indicative of a bigger and more expensive problem.

Hammerhead · September 14, 2013, 12:21 PM

The USPs are the finest polymer guns made IMO. The chances of it being the gun's fault are slim to none. Stop shooting the crappy steel ammo and I'll bet the problem disappears.

745SW · September 14, 2013, 06:24 PM

Rather strange to have a case rupture with one brand of ammo and bulging with another. Has lead ammo ever been used in the pistol? Check the barrel for any obstruction.

SavJosh · September 20, 2013, 07:58 AM

Found a pic, guess I did take one

September 13, 2013, 12:05 PM	#1
SavJosh Junior Member Join Date: September 13, 2013 Posts: 3	H&K USP .40 split steel case Could be used as a warning against using steel cases, but I'm wondering if it also has something to do with my gun. I've fired maybe 2000 rounds out of it in its 7 year life with me, maybe even less than that. I clean it after every shoot though, and take good care of it because its a really nice piece. Last time I took it out to the range though, I used some TulAmmo .40S&W since it was the only thing on Walmart's shelves. I'd fired it through the gun before without issue, but this day a case got stuck in the chamber. Very stuck, had to disassemble, stick a pencil down the barrel and tap it out with the slide. I picked up the case and it had a split down the length of the case, beginning maybe 3/8ths of an inch from the head and ending about 1/8th of an inch before the bevel at the bottom of the case. The split itself slightly thicker than a beard hair. Sorry I dont have pictures, but hopefully thats descriptive enough. I ran a couple more TulAmmo (glutton for punishment) and about 1 out of 6 or 7 shots did this. A few weeks later I was finally able to get some Federal brass ammo from Walmart and I took it out. The brass isnt splitting, but I am noticing an ever so slight bulge at the bottom. Placing them back into the barrel they slide right in and out so I'm just not sure if it was a bad batch of crap steel ammo or if my gun has a problem Any advice is greatly appreciated.

September 13, 2013, 04:59 PM	#2
PSP Senior Member Join Date: June 2, 2006 Location: Bowling Green Virginia Posts: 4,487	deleted reply

September 13, 2013, 06:31 PM	#3
James K Member In Memoriam Join Date: March 17, 1999 Posts: 24,383	I don't know for sure about that ammo, but in some wartime ammo case splits resulted from hastily made powder that did not have all the acid washed out of it. When the ammo was stored horizontally, the acid seeped to the bottom (that is the side) of the case and ate partially through the case. When the round was fired, it split along the weakened line. Jim

September 14, 2013, 12:28 AM	#4
SavJosh Junior Member Join Date: September 13, 2013 Posts: 3	Well, this ammo was factory stuff, but being cheaper ammo than most everything else it may be a bad batch of some sort.... Then there's the possibility of it being older ammo, as this stuff had been sitting on my shelf for 6+ months though not laying horizontally. I'm just hoping it was a bad batch but I'm wondering if it may be indicative of a bigger and more expensive problem.

September 14, 2013, 12:21 PM	#5
Hammerhead Senior Member Join Date: May 31, 2004 Location: Minnesota Posts: 2,432	The USPs are the finest polymer guns made IMO. The chances of it being the gun's fault are slim to none. Stop shooting the crappy steel ammo and I'll bet the problem disappears.

September 14, 2013, 06:24 PM	#6
745SW Senior Member Join Date: August 25, 2011 Location: California Posts: 776	Rather strange to have a case rupture with one brand of ammo and bulging with another. Has lead ammo ever been used in the pistol? Check the barrel for any obstruction.