P7M13 Question

[branrot]

My P7M13 has been jamming lately. After about 30 rounds, the slide starts to get stiff, and eventually it won't even open fully. I've been shooting reloads (my reloads; Hodgdon HP-38 powder), and am concerned that maybe some powder is getting into the gas system (the guy at the range told me the P7 didn't have a gas system... it has a gas system, right?). Is my speculation that the problem is with the ammo correct?

Yes, I know I should clean the gun (already did), and try it with factory ammo (have the ammo at home), but I'm not going to be at the range for at least 2 weeks (going out of town this weekend). Thanks for your help.

 

[HKP9S]

Branrot,

The P7 Series guns have what you might describe as a reverse gas system.

I am going to go into a lot of detail here so those who read this post and do not know a lot about the gun will be able to follow along.

Traditional gas operated firearms bleed expanding gasses from a hole in the barrel operate the mechanism by pushing a piston to drive the slide back, eject the spent case and load a new round into the chamber.

The P7 Series pistols bleed gas off into a chamber to keep the slide closed until the bullet has left the barrel, from that point the recoil of the fired round actuates the mechanism.

Keeping that system clean is important. Do you have the two piston chamber cleaning tools that come with the gun? They are a flat piece of stamped metal used to scrape the sides of the chamber and a bronze brush, similar to a bore brush, used to remove debris. If not, get them from an HK dealer in your area or search the internet. Clean the chamber thoroughly but do not leave a bunch of oil in there or it will smoke. Next use a soft nylon bristle tooth brush and a little solvent to clean the clean the piston hanging from the front of the slide. A little fouling is normal, but if more than one or two rings are caked, that could be your problem. Dry both the piston and chamber before reassembly.

Next question is about your reloads. You say you used HP38. That is a high quality powder, relatively clean and should not cause problems by itself. What kind of bullets are you using? Are they lead or jacketed? Jacket bullets are Required for all HK firearms, especially the P7. Lead bullets will jam it up in a heartbeat and can cause tremendous damage.

Hope this helps a little. Keep us informed on how it goes.

 

[Ehornad]

Bad ammo, period.

I had some ammo one time that was so bad, it locked the slide up after 13rnds,

You should be goo for 500-1000 rounds of quality FMJ before that happens.

Luckily I've got a range ammmo manufacture who knows what he's doing, his stuff will 1000rnds

email me if you want his #

 

[HKP9S]

FYI,

If you really want to go the long distance between cleanings, try Winchester's WinClean ammo. It is amazing how clean it is.

 

[Peter M. Eick]

Since you reload, try some power pistol. My PSP's seem to like it the best. I have shot as much as 750 rnds in one day with no problems (other then a hot hand) with PP.

Good luck.

 

[Gary H]

Clean the thing. Also, the P7 series likes it wet. A Park Service armorer told me to keep the slide well oiled. Are you using M13, or M10 magazines? There are slight differences, but most of us have found that the M10 mags work without problems. I've had unburnt powder problems with other powders when shooting light loads in the P7's.

 

[TooTech]

When you cleaned the gun you also cleaned the gas piston and cylinder, right?

And you're not using lead slugs I hope. Jackets only for the P7.

 

[Greg Bell]

Give the gas cylinder a good cleaning with the supplied (hopefully) tool and brush. Switch to commercial, jacketed ammo or prepare to experiment until you get some clean powder(still w/ FMJ). Any reasonable commercial FMJ will work as long as it is 100 grain or better. P7M13, oh Lord in heaven why did I sell you!!

GHB