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Well I took the members advice and purchased a P7 form CDNN. I paid the premium for a new to excellent gun. The gun came in original box with manual and gas cleaning brush.

The P7 was unfired. The only indication that it was used was the grip screws which showed removal with a poorly fitting screw driver.

I have always been impressed with close tolerance machining and innovative design. The P7 is a work of art with respect to these items.

I field striped the gun to clean and check for any safety items and noticed the barrel crown was very irregular. It was not damaged just machined this way. I found this to be troubling as the rest of the gun showed great attendition to detail.

At the range three problems were uncovered. Worst was the gun seizes up into the third mag. At 10 yards in was not possible to place all rounds in a 5 inch circle and last; the recoil was very sharp for an 9 mm. This seamed to be caused by the slide slamming into the frame.

The slide lock-up was caused by a burr just inside the chamber which dug into the casing. I have removed this burr with a hard stone and will take the P7 back to the range hopefully this week. I plan to take four samplings of factory 9 mm ammo and a good rest to see if the gun is ammo sensitive.

I like to work on one problem at a time so the heavy recoil is on the back burner for now.

I would greatly appreciate your suggestions and thoughts concerning these problems. Thanks to everyone for your help. R S
 

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Sound like you got one that needs some TLC. It's an oldie but goodie.
First I would buy a set of nill grips (wooden) for this great weapon and get some new screws for the damaged ones.

The next thing I would do is give it a good cleaning!! Use the scraper and lube the crap out of it. shoot a few rounds through it and then clean again.

I really feel that the weapon has been sitting or being carried so long that it has become stiff.

The shooting is your problem. You may be "pulling " on the trigger or a multitude of other things.

The recoil will go away.

If you really do not like the weapon get hold of CDNN and they will make it right for you.

There is probably the same problem with the mag. either needs lubed good, taken apart or new springs.

Happy & Safe Shooting!! TJ
 

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Sorry about your problems with your P7, just a couple of observations. My experience with the P7 (and P7M8) is that the recoil is "snappy", almost similar to a .40 cal. than many of the pistols you might compare it against. I don't know if it's because of the delayed blow-back action, grip contour, or really low bore axis but that's how it feels to me. I've never shot a P7 that was not extemely accurate, should be 2" (or better) at 10 yards. Perhaps your concern for the recoil or having to squeeze cock the pistol has you a little off. One last thought. You mentioned it appears the pistol was never fired. Perhaps it just appears that way and you might check the gas tube for carbon fouling. That could cause the slide to jam and might even contribute to the feeling of a too heavy recoil. I know you believe a burr in the chamber was the culprit but it might be due to fouling in the gas tube restricting piston travel, just an idea. It's kind of rare for someone to be unhappy with the P7 for the reasons you mentioned. Finally I have no idea what you mean by the barrel crown being machined in an irregular way, pics might help. Good luck!
 
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Texas Jim & Custom 60 Thanks for the reply. A little clarification. As a rule I clean, lub and inspect all new or used guns before I shoot them for the first time. Up on inspecting the P7 I found it to be clean with no signs of ever being fired. The gas piston was bright without any carbon build-up. The piston recess was clean without any signs of carbon. The breach face showed no markings and the barrel did not have any striations.

Thanks for the heads up on the recoil. I am not as a rule recoil sensitive. The sharpness of the recoil surprised me. Has anyone installed a stronger recoil spring on the P7? If so how did this affect the gun?

TJ thanks for the tip on the Nill grips.

As for accuracy I will take a trip to the range and try to determine if its me or the gun. I will let you know how this comes out. R S
 

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If you like to take your gun apart, I wouldn't recommend the Nil grips. They fit tightly, and tend to break if removed often. As far as the problems you are experiencing, it sounds highly unusual for a P7 to have such difficulties. If you don't mind, what ammo were you using?

Consider calling Travis at HK Trussville. If the gun is out of spec, he'll find it! The first question they will ask is what ammo you were using. The P7 was designed to run with 124 grain standard velocity ammo, and anything else cause wierd stuff to happen sometimes. Also, no aluminum or steel cased ammo. They'll lock up a P7 tighter than the Kennedy assasination files. Good gun you have. Hope everything works out for ya!
:87:
 

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Texas Jim & Custom 60 Thanks for the reply. A little clarification. As a rule I clean, lub and inspect all new or used guns before I shoot them for the first time. Up on inspecting the P7 I found it to be clean with no signs of ever being fired. The gas piston was bright without any carbon build-up. The piston recess was clean without any signs of carbon. The breach face showed no markings and the barrel did not have any striations.

Thanks for the heads up on the recoil. I am not as a rule recoil sensitive. The sharpness of the recoil surprised me. Has anyone installed a stronger recoil spring on the P7? If so how did this affect the gun?

TJ thanks for the tip on the Nill grips.

As for accuracy I will take a trip to the range and try to determine if its me or the gun. I will let you know how this comes out. R S
Brain dump here -

Unless the existing spring is weak and the slide is hitting against a hard stop instead of the spring stopping and then reversing the motion, a stiffer spring will shorten the time it takes for the slide to reverse directions which is the opposite of what you want to decrease recoil.

You want the slide energy to be gradually transferred to the frame through the spring, not more quickly.
 
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Discussion Starter #7
At the range with P7

Moonshiner & AviatorDave........About the ammo, Winchester white box, Triton and Speer all 115 grain. The removal of the burr in the chamber had a positive effect on accuracy which exceeded my expectations All shooting was at 10 yds. off a rest. The gun does not like the Speer load at all shooting 5" groups. The Triton and Winchester shoot 2 to 3 inch groups. The groups where shot by three different experienced shooters with similar results.

This leaves me with this question: How much affect does the uneven crown have on these shooting results? The quality of workmanship of the P7 made me hope for better accuracy. What do you think? R S
 

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Moonshiner & AviatorDave........About the ammo, Winchester white box, Triton and Speer all 115 grain. The removal of the burr in the chamber had a positive effect on accuracy which exceeded my expectations All shooting was at 10 yds. off a rest. The gun does not like the Speer load at all shooting 5" groups. The Triton and Winchester shoot 2 to 3 inch groups. The groups where shot by three different experienced shooters with similar results.

This leaves me with this question: How much affect does the uneven crown have on these shooting results? The quality of workmanship of the P7 made me hope for better accuracy. What do you think? R S
What do you mean exactly by an "uneven crown"? Is it dinged or something? You might be able to have a machinist turn a few .010"s off the end to even it up.

A friend of mine that had zero experience with shooting bought an old Ruger just like my P85. We were both shooting one day, and his groups were terrible. So we switched, then mine were terrible. I looked at his, and there was a spot on the crown where some material was pushed towards the bore so that it was noticeably not round. I took it to work, chucked it up in a lathe and cut about .030 off the end so it was round again, and his groups were 60% smaller next time. The difficult part will be that the P7 takes some work to remove the barrel since it is mounted to the frame. But a little indentation can cause a big difference in accuracy.
 
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Discussion Starter #9 (Edited)
Uneven Crown.

/Aviator.... I wish my camera would take a close-up of the crown. I know this would help. I will try to explain what I am seeing. With the sight being at 12 O'clock from 6 to 10 the radius is not uniform and breaks off sharply (tapered). This does not appear to be from a strike, but I can not rule this out. It is very noticeable to the naked eye.

If I could remove the barrel I could recut the crown, but for a gun this costly I know I should leave it to an expert.

HK informed me that there is not a warranty on P 7 trade-ins. I don't have a problem with their position, but this leaves me with few if any good options

R S
 
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