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Some of the discussions here about the P320 trigger reset and double-click thing have me wondering about the reset on my P7M8. It works fine in controlled fire, but I know on at least 2 occasions during rapid fire, the trigger has failed to reset. A new cartridge chambered, but the trigger did not reset, and the firing pin was in the forward position. I had to release the squeeze cocker and re-squeeze it in order to cock it again.

Is anyone else familiar with or aware of this happening with the P7M8? Unfortunately, it's one of my few pistols that I'm really not that familiar with all the inner workings and never really studied the phenomenon.

I also forgot to mention that I had the pistol hard chromed by Tripp's Research years ago, and I'm wondering if maybe something got reinstalled incorrectly. I don't recall having the issue before, but I can't say I ever rapid fired it beforehand.
 
Posts: 872 | Registered: October 08, 2000Reply With QuoteReport This Post
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Any chance that you are short stroking the trigger ? ( Not letting the trigger go far enough forward before starting another trigger pull. )

Edit: Oops , I just re-read you note.....short stroking wouldn't leave the firing pin in the un-cocked position. Just ignore me ! Wink
 
Posts: 1264 | Location: Idaho | Registered: October 21, 2007Reply With QuoteReport This Post
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Check the striker bushing and pin for damage and proper installation. Try replacing the firing pin/striker spring.

The owners manual notes:
"CAuTION: FurTHEr dISASSEMBLY OF THE FIrING PIN IS NOT rECOMMENdEd; HOWEVEr, IF FOr ANY rEASON THE FIrING PIN ASSEMBLY IS FurTHEr dISASSEMBLEd, CArE MuST BE TAKEN THAT THE FIrING PIN COLLAr PIN IS COrrECTLY SEATEd IN THE SLOTS OF THE FIrING PIN COLLAr. IMPrOPEr ASSEMBLY MAY CAuSE MALFuNCTION."

Sorry about the formatting. Copy/paste from a .pdf and I'm too lazy to fix.


I'll have to look at mine more closely to see if there's any reason the pistol would cycle without resetting the striker.


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Posts: 1859 | Registered: June 25, 2010Reply With QuoteReport This Post
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I am familiar with the firing pin assembly and collar, etc. and that part appears to be fine...I usually remove that as part of normal field stripping for cleaning and inspection. I guess I can imagine a scenario where I'm pulling the trigger so fast that the trigger bar/sear is already down before the slide even gets all the way back home into battery, and the firing pin can't even catch on the sear. I really doubt I'm pulling the trigger that fast...maybe so. But after doing a cursory Google search on the issue (and finding nothing), I did see that a poster on another forum even claimed that the P7 was his fastest rapid-firing pistol.

I was thinking it might be an issue with the disconnector or spring...but that's getting down into the guts that I still don't fully understand.

Another, more plausible explanation just occurred to me, too: I simply might not be releasing the trigger forward enough to fully reset before I start yanking on it again Smile The trigger return spring isn't exactly all that stiff or positive...
 
Posts: 872 | Registered: October 08, 2000Reply With QuoteReport This Post
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Try reading:

http://www.hkpro.com/forum#/topics/113007?page=1

Sounds very familiar. HK tried springs first but ended up replacing sear.

Hope that helps


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Posts: 1859 | Registered: June 25, 2010Reply With QuoteReport This Post
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Crud, for some reason that only takes me to the main forum page. I even tried registering, and I was REALLY trying to avoid that Smile My search there didn't turn up any threads that looked like they'd be pertinent...what did you search for? And in what sub-forum?
 
Posts: 872 | Registered: October 08, 2000Reply With QuoteReport This Post
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I have three of the PSP version, with many thousands of rounds through them. I have never seen that.

However, the internals of the P7 are very complex. I like comparing the guns to a safe door: A sturdy frame with a complicated mechanism inside.

The firing pin spring is a fairly easy part to replace. The recoil spring, which can become shorter with extensive use, is even easier. If that has happened it could affect the reset due to affecting the cycling of the slide.

Wolff has the springs, in sets or individually. (Or they did a few years ago when I bought some from them.)
 
Posts: 327 | Location: Frankfort, Kentucky.  | Registered: November 26, 2008Reply With QuoteReport This Post
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That problem is typically caused by a weak firing pin return spring. It's the smaller of the two pins on the firing pin(part #12 on the parts schematic). A quick fix is disassembling the firing pin and stretching the spring and reinstalling it. Ideal fix is replacing the spring. I've had this happen on two p7m8's.
 
Posts: 301 | Registered: November 07, 2006Reply With QuoteReport This Post
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quote:
Originally posted by ether:
Crud, for some reason that only takes me to the main forum page. I even tried registering, and I was REALLY trying to avoid that Smile My search there didn't turn up any threads that looked like they'd be pertinent...what did you search for? And in what sub-forum?


Weird. I'm not registered to that forum. The thread title is: P7PSP failure to cock
Google that and it should be the first result.


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Posts: 1859 | Registered: June 25, 2010Reply With QuoteReport This Post
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quote:
Originally posted by DaveS:
That problem is typically caused by a weak firing pin return spring. It's the smaller of the two pins on the firing pin(part #12 on the parts schematic). A quick fix is disassembling the firing pin and stretching the spring and reinstalling it. Ideal fix is replacing the spring. I've had this happen on two p7m8's.


Thats probably where I'd start. Cheapest, easiest potential solution. Then move on to sear if it doesn't work.


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Posts: 1859 | Registered: June 25, 2010Reply With QuoteReport This Post
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quote:
Originally posted by BuddyChryst:
quote:
Originally posted by DaveS:
That problem is typically caused by a weak firing pin return spring. It's the smaller of the two pins on the firing pin(part #12 on the parts schematic). A quick fix is disassembling the firing pin and stretching the spring and reinstalling it. Ideal fix is replacing the spring. I've had this happen on two p7m8's.


Thats probably where I'd start. Cheapest, easiest potential solution. Then move on to sear if it doesn't work.



Thanks guys, that's exactly what it was. I put in a new firing pin return spring and took it out Saturday and rapid-fired it without a hitch.
 
Posts: 872 | Registered: October 08, 2000Reply With QuoteReport This Post
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Thanks for following up with the solution that worked. That helps everyone who may run into a similar problem.
 
Posts: 301 | Registered: November 07, 2006Reply With QuoteReport This Post
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