New TP9 - failure to fire last round in mag?

[indysims]

Took my new TP9 to the range today for 200 roundbreak in. Across three magazines I found that about 60% of the time I hada failure to fire/strike on the last round. Seem more prevalent with one magthan the other two, but I had it happen across all mags. The last roundchambered, but it just seemed that the striker didn't reset. The triggerpull was dead, with no click. Didn't matter if the mags were loaded with 2-3-4 upto eight, still happened on the last round.

Any experience with this? Any known solution?

[hardluk1]

Is the last round fully chambered ? No dimple at all on the primer ?

[CJB]

Question #1 - What ammo were you using?

[indysims]

No dimple what so ever. Cannot confirm fully chambered because I would maipulate the slide to drop the round, didn't "peek" in first to see if round was fully chambered. However dropping mag didn't allow the round to fall out mag well.

Remington UMC

[indysims]

I would think that for the slide cycle enough to eject spent casing, that would be enough to reset the striker. Manipulating the action manually with snap-caps I can reset the trigger with less than an inch of movement, not near enough to eject the round.

[SmokyT]

Check to see 1) if the trigger reset spring is bent or deformed; and 2) if the cocking cam spring is broken.


1) I once experienced a similar case where the striker was failing to reset just occasionally but not all the time. Upon inspection, I found out that the trigger reset spring was slightly deformed (i.e., open too widely), causing the trigger bar occasionally failing to be raised to engage the cocking cam. If that is case, you need to properly reshape the trigger reset spring or replace it with a new one.


2) When the cocking cam spring of my PM9 broke, the striker failed to reset most of the time but not all the time. I didn't know it was caused by the broken cocking cam spring until I field stripped the gun and check the cocking cam. If the cocking cam of your gun rotates freely without spring resistance, you need to replace the broken spring inside by taking the gun's trigger mechanism completely apart. You can do it yourself fairly easily, but you may want to send your gun back to Kahr just to have everyting inspected by the factory.


If neither turns out to be the case, you really should sent it back to Kahr to have them find out the exact cause of the problem....

[Scarywoody]

I would disassemble the magazine and make sure that spring isn't backwards. It does happen.

[Bawanna]

I can't figure out why always the last round. Any of the above could effect any random round except the mag spring backwards and sounds like the issue is the striker, not getting the round into the chamber.

[indysims]

I can't figure out why always the last round. Any of the above could effect any random round except the mag spring backwards and sounds like the issue is the striker, not getting the round into the chamber.

Exactly my thoughts. But it was very consistent. I loaded 2 rounds, 3 rounds, 5 rounds etc and if it happened, (as stated, about 60%) it was last round.

[indysims]

Planning on a short range trip tomorrow, about 50-100 rounds. Collecting information on this issue, paying close attention to rule out something I might be doing and trying to examine exactly how it is happening.

[indysims]

I would disassemble the magazine and make sure that spring isn't backwards. It does happen.

I did that when I cleaned up after the break in range trip. They were correct.

[indysims]

So 2nd range trip resulted in no malfunctions as described in opening post...

I put 42 rounds of TUL Ammo through all three magazines with a total of 13 mag changes, and 46 rounds of Blazer Brass through all three magazines with 12 mag changes. I worked with varying numbers of mag loads, anywhere from 3-8.

I'm hypothesizing these options:
-The problem was resolved with a proper cleaning and lubrication and/or break in.
-The problem is dependent on ammo type
-The problem was caused by something I was doing.

I'll keep an eye on this and try to re-create the malfunction using the UMC ammo that I was using in the first range trip. If It doesn't happen again I'll test my JHP carry ammo and call it good to go for now.

[landman]

glad to hear it seems to have resolved itself.