sgt127
August 28, 2003, 02:24 AM
Personal observations:
Recently purchased a PM9. Took it out and shot about 200 rounds of assorted ammo through it to break it in. The last 50 were Federal 9BPLE 115 gr +P+. When I got it home to clean it, I discovered a pretty sizable burr had kicked up on the top right side of the barrel hood. Another was starting on the front left corner of the locking lug where the recoil spring fits against it. I stoned them down, went back to the range the next day and fired another 150 Rnds of asst ammo including about 30 +P+. The burrs returned. Contacted Kahr and they advised to send in the top half of the gun.
(Kahr was great, Fed-Exed the parts back to me, 5 days total from when I shipped it to back in my hands)
Shot another 150 or so rounds of asst. white box Winchester and S&B 124 gr SP. Took the gun apart, no sign of peening. Fired 30 rounds of +P+ and discovered it was starting again on a brand new barrel and new slide.
I have a MK9 that has well over 200 rounds of the same +P+ ammo through it, no signs of wear at all. A friend of mine has the P9, he has also shot the Federal and alot more Cor-Bon +P, again, no wear. (as an aside, there are considerable differences between the P9 and the PM9, there is alot more polymer in the frame around the slide stop pin, the barrel locking lugs are radically different and the inside of the slide is machined very differently along the barrel, though there is only about 7 grams of weight difference between the two slides)
My conclusion: (And this is only my opinion) The frame flexes on the Micro allowing the barrel to twist in the direction of the torque of the bullet going down the barrel. Based on the peening being on the top right and lower left portions of the barrel. I noticed while firing the +P+, the slide would "catch" briefly before going the rest of the way into battery, leading me to believe the barrel was slightly off center and the hood was hitting the slide, it would then straighten out and the slide closed the rest of the way.
Based on this, I'm going to stick with regular Federal 9BP ammo for the polymer gun. There was nothing catostrophic that occured and the gun would likely shoot several hundred more rounds before it became a real problem, but, I think its beating the gun up more than it needs to.
I suppose the analogy is, you CAN drive your car at 120 MPH all the time, but, parts are going to wear out alot faster then if you drove it at 60 MPH.
See attached photo of the top of the barrel hood, this was the old one just before I sent it in. Not the best, but you can get the idea.
Interested if anyone has any other opinions, or has a better diagnosis.
Recently purchased a PM9. Took it out and shot about 200 rounds of assorted ammo through it to break it in. The last 50 were Federal 9BPLE 115 gr +P+. When I got it home to clean it, I discovered a pretty sizable burr had kicked up on the top right side of the barrel hood. Another was starting on the front left corner of the locking lug where the recoil spring fits against it. I stoned them down, went back to the range the next day and fired another 150 Rnds of asst ammo including about 30 +P+. The burrs returned. Contacted Kahr and they advised to send in the top half of the gun.
(Kahr was great, Fed-Exed the parts back to me, 5 days total from when I shipped it to back in my hands)
Shot another 150 or so rounds of asst. white box Winchester and S&B 124 gr SP. Took the gun apart, no sign of peening. Fired 30 rounds of +P+ and discovered it was starting again on a brand new barrel and new slide.
I have a MK9 that has well over 200 rounds of the same +P+ ammo through it, no signs of wear at all. A friend of mine has the P9, he has also shot the Federal and alot more Cor-Bon +P, again, no wear. (as an aside, there are considerable differences between the P9 and the PM9, there is alot more polymer in the frame around the slide stop pin, the barrel locking lugs are radically different and the inside of the slide is machined very differently along the barrel, though there is only about 7 grams of weight difference between the two slides)
My conclusion: (And this is only my opinion) The frame flexes on the Micro allowing the barrel to twist in the direction of the torque of the bullet going down the barrel. Based on the peening being on the top right and lower left portions of the barrel. I noticed while firing the +P+, the slide would "catch" briefly before going the rest of the way into battery, leading me to believe the barrel was slightly off center and the hood was hitting the slide, it would then straighten out and the slide closed the rest of the way.
Based on this, I'm going to stick with regular Federal 9BP ammo for the polymer gun. There was nothing catostrophic that occured and the gun would likely shoot several hundred more rounds before it became a real problem, but, I think its beating the gun up more than it needs to.
I suppose the analogy is, you CAN drive your car at 120 MPH all the time, but, parts are going to wear out alot faster then if you drove it at 60 MPH.
See attached photo of the top of the barrel hood, this was the old one just before I sent it in. Not the best, but you can get the idea.
Interested if anyone has any other opinions, or has a better diagnosis.