[ScorpioMk]

I've put 500+ rounds through my 94k and have had issues with ejection and jamming up. The ejector is bent to one side a bit and I assume that sometimes its hanging up on the bottom of the bolt head and keeping it from cycling fully. Gonna order a new ejector, no big deal.

Also ejection has been weak, do the 94k's come with 100 degree locking piece? If they do I was planning on ordering an rcm 110 and seeing if that fixes it since that seems to be an issue with the k guns. Have shot a bunch of different types of 9mm, all 115 grain. Bullets really just seem to flop out. This is my only real question, other stuff is just things I have noticed. EDIT: Wanted to add its got about a .013 bolt gap.

Also the mag that came with it is getting scraped up pretty good on top. Few pics below, last pic is a korean mag and it didnt get scraped up too much. Big deal? Not sure, but it seems to have scraped off what it needed and isnt getting any worse now. Dont have any german mags to check it against, just the one mke mag and a few ati green box mags.

other mag.

Pics of gun just cause

 

[Blackpaladin]

Nice pistol! I am curious to see how this turns out.

 

[SWolff]

Try a German magazine. The change in LP will won't effect much in semi auto. I would check the ejector spring to make sure its not broken, get a new ejector if its bent, check your extractor spring

I noticed PMC in the background. PMC is pretty weak ammo and the ejection is much less than other ammo ive shot in many different 9mm MP5s ive shot. I've almost 2500+ rounds of Aguila 124gr without a hitch and it not too dirty and moves a 124gr round pretty well

 

[ScorpioMk]

The pmc box is marked independence 115 but it's blurry, I've maybe shot some in it but mostly federal 115, rbs, bvac, maybe a few wwb. All the ammo runs fine in my beretta, my diamondback and friends glocks and xd's. I'm the only one seeing a problem with the mke. Why would going from 100 to 110 only make a difference for full auto?

 

[SWolff]

Changing the LP slows the cyclic rate down in F/A. The 110 would not be what you want in your gun anyway. Stick with what you have. The independence are factory reloaded ammo. Definitely try more ammo. Try Federal, Aguila, Prvi, S&B.

They will run fine in pistols, but these guns need a little more power to run right. You won't need +p, but more potent ammo is a good idea

 

[ScorpioMk]

Does the locking piece not change the amount of energy it takes to unlock? What youre saying doesnt make sense to me since an 80 degree piece is recommended for shooting with a silencer which has more back pressure. My thought was that if this gun has a 100 locking piece a 110 would take less energy to open, making it cycle better with ammo that's not real hot. And I have tried the s&b too, had prolly 100 rounds through this gun. I think most of the problem is the ejector jamming up sometimes but the ammo falling out of the chamber makes me worry.

 

[programmatore]

Re: weak ejection... Are you limp wristing the pistol? In PDW configuration you have the stock against your shoulder offering some resistance but not with a pistol so you have to have a firm grip. Try using a single point sling and have it long enough that it is tight when you're shooting -- almost like you're pushing the pistol away from you.

 

[DJF]

scorpio,
Check all the usual......ejector lever lateral play, ejector tip and anything else that might be interferring with bolt travel, extractor & spring. Flutes cleaned really well. Well lubed, good strong ammo, etc. etc. Also what programmatore mentioned about "limp wristing". You can also bump up your bolt gap with plus rollers to see if that helps. The K's can be finicky because of their quick/short impulse cycle.
Dj

 

[ScorpioMk]

Gun is clean, lubed up and flutes clear that part is not a problem. I might order some plus rollers when I get the ejector just to give it a shot and also try and get some german mags. And as I said earlier I am going to buy a new ejector and spring I know that part needs to be replaced, but does anyone have a better answer to the locking piece question? sp89's came with a 110, and thats what my gun is a direct copy of. I understand that now hk says to use the 100 degree piece but I have found multiple threads on people needing 110 pieces to operate. So does the mke come with a 100 or 110? I am trying to rule that out as a problem, if they come with a 110 then I know thats not the issue.

 

[programmatore]

I'm not sure what MKE locking piece I have on the AT-94K SBR since it is unmarked. However, I have swapped out the RCM 100 degree locking piece from my full-size MP5 (Dakota Tactical D54P SBR) to see if I'd notice a difference. I tried both the MKE and the RCM bolt heads and locking pieces -- suppressed and un-suppressed -- on my AT-94K and did not notice any difference.

As previously mentioned, check the extractor spring to make sure it is not bent and that there is no play in the extractor, try using German mags (although I've never had problems running the MKE mag and ATI-marked Korean mag on my AT-94K), try different ammo (my personal choice for plinking in the range is the Sellier & Bellot 115gr), and see if tightening your grip makes a difference.

Good luck!

 

[ScorpioMk]

Replaced the extractor spring before the last outing, I initially thought that was a problem since I've heard once you get some fte it might have been bent. Any actual answers on the 100vs110?

 

[programmatore]

You will not notice any difference between the 100 and 110 degree locking pieces on semi-auto.

 

[ScorpioMk]

Do locking pieces change the amount of energy it takes to unlock the bolt or no? I understand the 110 vs 100 isnt the problem in your eyes but for educations sake why is it only an issue for auto guns? Shorter barrel sp89's come with a 110 which my gun is obviously a copy of so why wouldnt my gun use that same piece?

We dont even know if my gun has a 100 or 110 so I could already have a 110 and its not the problem anyways, if anyone knows please chime in on what the factory 94k's came with I would like to know for peace of mind.

 

[programmatore]

Read on: Guide to HK Locking Pieces

 

[ScorpioMk]

These are keyed to certain cartridge pressures and certain configurations of firearms.

And right about that shows that mp5k's use a 110, it talks about timing but not timing like the cyclic rate. Its talking about timing of the unlocking of the rollers and how the LP is paired for the configuration of the gun (like barrel length) and the cartridge.

Thus you have two different locking pieces for 10mm MP5s—a high impulse and low impulse. Adding a stock and suppressor to an MP5K will necessitate a different angle, and thus a different locking piece. MP5SDs need a different locking piece than an MP5, and so on.

 

[programmatore]

Well I guess you should try a 110 degree German locking piece then. I've tried both the 100 and 110 degree locking pieces on my MKE AT94K and did not notice any difference -- no difference in felt recoil and no difference in operation (both ran flawlessly).

 

[ScorpioMk]

Do you still have the factory piece? If you do could you compare it to your other locking pieces, I would love to know if the gun already has a 110 or not.