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Posted: 10/24/2018 9:55:07 PM EDT

I was out shooting a P7M8 that I recently bought and I was occasionally experiencing a failure of the gun to recock itself. A new round would load from the magazine and I still had a good grip. Resqeezing the grip would allow me to shoot normal again.

Any ideas as to what I can do to fix this?

Posted: 10/24/2018 10:03:42 PM EDT

[#1]

Is the piston and cylinder clean? Never had that issue, but might be it.

Posted: 10/24/2018 11:01:31 PM EDT

[#2]

The piston wasn't too bad but did have noticeable blue corrosion. I don't have any of the tools that originally came with the gun so I'll probably pick that up or at least the cheaper aftermarket one that hkparts.net sells.

I'll give the P7 a good cleaning and see what it does after that. Thanks for the help.

Posted: 10/24/2018 11:30:42 PM EDT

[#3]

What ammo are you shooting?

Posted: 10/25/2018 7:19:10 AM EDT

[#4]

Quote History

Quoted:
What ammo are you shooting?

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It was American Eagle 115gr.

Posted: 10/25/2018 8:42:22 PM EDT

[#5]

OP, has it happened to anyone else shooting the gun? I think you're letting loose just enough to decock, IMO.

Posted: 10/27/2018 12:17:40 AM EDT

[#6]

Are you saying the slide is not returning to battery or the striker is not resetting?

Also there are some YouTube vids on how to clean the gas chamber. Make sure it is dry. No lube. Also be careful when cleaning the piston. You don't want to use any mortal brush to clean carbon off. Piston could be out of spec.

Posted: 10/27/2018 12:40:45 AM EDT

[#7]

Had the same thing happen with a brand new P7M8.
My wife could shoot it without issue, but it would often fail to recock when I shot it.
I ended up taping the squeeze cocker in the depressed position and the issue still occurred.

The problem I suspect was with one of the springs inside the cocking mechanism. Unfortunately a spilled soda and a bad refinish job meant that we never got to verify the cause

Posted: 10/27/2018 6:33:32 PM EDT

[#8]

Quote History

Quoted:
OP, has it happened to anyone else shooting the gun? I think you're letting loose just enough to decock, IMO.

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Quote History

Quoted:
OP, has it happened to anyone else shooting the gun? I think you're letting loose just enough to decock, IMO.

No one else has shot the gun yet since I bought it used. I was thinking the same thing and will see about getting someone else to shoot it.

Quoted:
Are you saying the slide is not returning to battery or the striker is not resetting?

Also there are some YouTube vids on how to clean the gas chamber. Make sure it is dry. No lube. Also be careful when cleaning the piston. You don't want to use any mortal brush to clean carbon off. Piston could be out of spec.

The striker isn't resetting. The second time it happened I payed more attention to what was going on and I had to release my grip and squeeze the grip again to get the striker to cock back. I'll take a look at some of those YouTube videos, thanks.

Quoted:
Had the same thing happen with a brand new P7M8.
My wife could shoot it without issue, but it would often fail to recock when I shot it.
I ended up taping the squeeze cocker in the depressed position and the issue still occurred.

The problem I suspect was with one of the springs inside the cocking mechanism. Unfortunately a spilled soda and a bad refinish job meant that we never got to verify the cause

I see there is a firing pin return spring. HKparts' website has a review with the exact problem with they saying the spring fixed it. Now if I could just find one in stock somewhere. You'd think springs would be a part that would be easy to come by.

Posted: 10/27/2018 6:45:26 PM EDT

[#9]

Parts :-)
The gun has not been made in 20 years.
Using 3 hands take the firing spring apart and see if one of the springs is broken.
I'll look in my parts box tomorrow for an extra.

Posted: 10/27/2018 10:54:57 PM EDT

[#10]

Quote History

Quoted:

No one else has shot the gun yet since I bought it used. I was thinking the same thing and will see about getting someone else to shoot it.

The striker isn't resetting. The second time it happened I payed more attention to what was going on and I had to release my grip and squeeze the grip again to get the striker to cock back. I'll take a look at some of those YouTube videos, thanks.

I see there is a firing pin return spring. HKparts' website has a review with the exact problem with they saying the spring fixed it. Now if I could just find one in stock somewhere. You'd think springs would be a part that would be easy to come by.

View Quote

Just call up HK's customer service, you'd be surprised what they can find if you ask them.

Posted: 10/29/2018 11:40:04 AM EDT

[#11]

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Quoted:

Just call up HK's customer service, you'd be surprised what they can find if you ask them.

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HK CS used to be great in getting P7s up and running until about a year ago.......now they're a brick wall on squeezecockers. All they say is that they no longer support/service the P7 line.

Posted: 11/2/2018 11:17:00 PM EDT

[#12]

Sounds like it might be a problem with one of the striker springs. I'm not an armorer, so I wouldn't know which one might be bad, but, I'd take out the striker group and check the two springs for issues.

Posted: 11/2/2018 11:19:55 PM EDT

[#13]

Quote History

Quoted:
HK CS used to be great in getting P7s up and running until about a year ago.......now they're a brick wall on squeezecockers. All they say is that they no longer support/service the P7 line.

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Quote History

Quoted:

Quoted:

Just call up HK's customer service, you'd be surprised what they can find if you ask them.

HK CS used to be great in getting P7s up and running until about a year ago.......now they're a brick wall on squeezecockers. All they say is that they no longer support/service the P7 line.

Bruce Gray at Gray Guns used to work on HK P7 series of pistols.

Posted: 11/4/2018 12:08:57 PM EDT

[#14]

I was able to find one striker spring on ebay and the other from HKparts. I'm going to give that a try and see how it does after that.

Posted: 11/14/2018 12:45:54 PM EDT

[#15]

It can be very difficult to diagnose a P7 without having it in hand and very few people are knowledgeable enough to work on them. I took a P7 armorer's course earlier this year and it allowed me to become proficient in working on mine. Also, calling HK will do you 0 good. James Williamson is the man you want to speak to and send your gun to. He goes by Marine0303 on HK Pro and also has a Vendor Page under Teufelshund Tactical. He's an HK guru & specializes in P7's. Good luck!

Posted: 12/12/2018 8:51:34 PM EDT

[#16]

I haven't had a chance to try it out yet but I replaced the firing pin return spring last night. The new one was quite a bit longer then the old one so I feel fairly confident that that was my problem. I wish there was a better source for these springs. Hopefully in the future someone like Wolff will make resonably priced springs for the P7 series.

Posted: 12/13/2018 9:02:11 AM EDT

[#17]

Quote History

Quoted:
I haven't had a chance to try it out yet but I replaced the firing pin return spring last night. The new one was quite a bit longer then the old one so I feel fairly confident that that was my problem. I wish there was a better source for these springs. Hopefully in the future someone like Wolff will make resonably priced springs for the P7 series.

View Quote

Wolff can & does make any spring needed by an owner. "Reasonable price" may or may not enter that equation...........

But you're on the mark when a new spring is much longer than the old one. That's how I check my recoil springs, if they're more than 1 inch different then the old one is gone.

Hope your gun is now fixed.

Posted: 12/15/2018 8:32:01 PM EDT

[#18]

I took my P7M8 to the range today and replacing the springs didn't fix my problem. The pistol still loads a new round no problem but the firing pin doesn't recock itself every time. On average it happens one in every ten rounds. I've also taken the hkparts.net tool and scraped out the carbon, although there wasn't much. Any other ideas out there to try or should I go straight to contacting the expert at Gray Guns?

Posted: 12/15/2018 10:54:55 PM EDT

[#19]

Forgive me for incorrect nomenclature, but the firing pin spring is captured on the firing pin. Make sure it's doing so by taking the firing pin out & checking the spring on it.

My apologies if you already have done this.

Posted: 12/17/2018 1:58:15 PM EDT

[#20]

Quote History

Quoted:
Forgive me for incorrect nomenclature, but the firing pin spring is captured on the firing pin. Make sure it's doing so by taking the firing pin out & checking the spring on it.

My apologies if you already have done this.

View Quote

No need to apologize. I do have both springs captured over the firing pin.

Posted: 1/5/2019 12:27:05 PM EDT

[#21]

Another little update. I think I got the pistol working this time. I came across this website. (bevfitchett.us) There, I found some trouble shooting for the P7 not recocking after being fired. I bought a new sear lever spring from Ebay and replaced my old one that was very worn. Today, I put 4 magazines worth of ammo through with no issue. Before I could only get through 1 magazine at best. I'm going to put more rounds through the P7M8 when I get the chance but for now its looking like the problem is fixed.

Posted: 1/5/2019 3:48:20 PM EDT

[#22]

Great job, keep us posted.

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