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CTG
March 31, 2017, 14:09
So I bought an HK91, and I love it so far. Makes for an excellent companion to my L1A1. But the trigger pack moves slightly, and that bugs the hell outta me. It's a tiny bit of back and forth movement, nothing side to side or up and down.
I really need to fix this. What's the best way to go about doing so?

NFADLR
March 31, 2017, 15:16
I would swap out the grip frame as that fmpov is what registers the trigger pack onto the upper and then there is also the shelf mfg tolerances.

CTG
March 31, 2017, 15:20
I would swap out the grip frame as that fmpov is what registers the trigger pack onto the upper and then there is also the shelf mfg tolerances.

FMPOV? And regarding tolerances, could I just insert something?

NFADLR
March 31, 2017, 15:54
FROM MY POINT OF VIEW.

No I wouldn't insert something but ymmv.

Do you wecsog?



FMPOV? And regarding tolerances, could I just insert something?

hkshooter
March 31, 2017, 17:54
The best fix is to tighten up the pin holes in the rear end of the grip frame. Install your grip frame and put the pins in without the stock and you'll see where the slop is.
Grip frames are cheap so replacing it is a good option but you may have to try a few to find one that fixes the problem. And then there's the clipped and pinned thing to consider, too.
The best way would be to weld up the front of the holes and then fit the frame to the rifle. Once done, have the frame refinished or spray it with paint. Or possibly lengthen the rear tang of the grip frame so the stock holds it tightly forward.
Don't insert or put anything up front, there are a couple of reasons why.
1) Anything you stick in there might come loose and jam up the works creating a safety concern.
2) Anything you stick up front will move the trigger pack to the rear. It's more desirable from a reliability stand point to keep the trigger group closer to the front than the rear. Of course, if it works no matter where in the slop range you fire it you could weld up the shelf to tighten the frame but that's the kind of mod that has FUBAR written all over it. Avoid that all together.

A third option is to finally admit that the rifle is a stamped steel German POS that doesn't deserve any quality attention or repair and send it to me. I'll be sure it gets treated like the POS it truly is. :rofl::angel:

superjc
April 01, 2017, 12:18
See if your selector is loose/worn; seems like that's what holds the thing in place

hkshooter
April 01, 2017, 20:11
See if your selector is loose/worn; seems like that's what holds the thing in place

Explain how the selector lever keeps the grip frame from moving.



I'll wait.

Klaus Von Richter
April 01, 2017, 20:15
So is it the trigger pack or the grip frame moving?

Klaus Von Richter
April 01, 2017, 20:18
The best fix is to tighten up the pin holes in the rear end of the grip frame. Install your grip frame and put the pins in without the stock and you'll see where the slop is.
Grip frames are cheap so replacing it is a good option but you may have to try a few to find one that fixes the problem. And then there's the clipped and pinned thing to consider, too.
The best way would be to weld up the front of the holes and then fit the frame to the rifle. Once done, have the frame refinished or spray it with paint. Or possibly lengthen the rear tang of the grip frame so the stock holds it tightly forward.
Don't insert or put anything up front, there are a couple of reasons why.
1) Anything you stick in there might come loose and jam up the works creating a safety concern.
2) Anything you stick up front will move the trigger pack to the rear. It's more desirable from a reliability stand point to keep the trigger group closer to the front than the rear. Of course, if it works no matter where in the slop range you fire it you could weld up the shelf to tighten the frame but that's the kind of mod that has FUBAR written all over it. Avoid that all together.

A third option is to finally admit that the rifle is a stamped steel German POS that doesn't deserve any quality attention or repair and send it to me. I'll be sure it gets treated like the POS it truly is. :rofl::angel:

If it's the grip frame/ lower moving it would be a lot easier to put it in a vise and squeeze it a little to bend it in, that way the lower will pinch the receiver and won't move back and forth. Also if it's the trigger pack moving this will help that also.

hkshooter
April 01, 2017, 20:38
If it's the grip frame/ lower moving it would be a lot easier to put it in a vise and squeeze it a little to bend it in, that way the lower will pinch the receiver and won't move back and forth. Also if it's the trigger pack moving this will help that also.

I interpreted the OP's comments as referring to the grip frame. It's common on the type, I've seen it on nearly every HK I've handled. Ironically, clones usually don't do this because the out of spec parts fit together so tightly the frames can't move.

Your idea of pinching together the grip frame won't work, the trigger pack won't allow it to bend in. It will tighten up the trigger pack to frame fit but even then, the frame will be bent back out when the pack is reinserted, making no change in how the grip frame fits the receiver.

The problem occurs because the grip frames were designed to be located by the front push pin. That pin being eliminated by the semi auto conversion there's nothing left to locate the grip frame but the rear pins where the fit isn't as intentional or well fitting. It's close enough to allow the rifle to operate and HK never saw fit to do anything else. As said above, those ideas will fix the issue.

CTG
April 02, 2017, 01:04
I interpreted the OP's comments as referring to the grip frame. It's common on the type, I've seen it on nearly every HK I've handled. Ironically, clones usually don't do this because the out of spec parts fit together so tightly the frames can't move.

Your idea of pinching together the grip frame won't work, the trigger pack won't allow it to bend in. It will tighten up the trigger pack to frame fit but even then, the frame will be bent back out when the pack is reinserted, making no change in how the grip frame fits the receiver.

The problem occurs because the grip frames were designed to be located by the front push pin. That pin being eliminated by the semi auto conversion there's nothing left to locate the grip frame but the rear pins where the fit isn't as intentional or well fitting. It's close enough to allow the rifle to operate and HK never saw fit to do anything else. As said above, those ideas will fix the issue.

Excuse my vague OP post. It's the trigger pack that moves back and forth. The pistol grip is rock solid. But the trigger pack will "click" back and forth a bit, and it's driving me nuts, regardless of how normal it is on the semi-only models.

Will swapping in a paddle release cure this then? Or is some other option necessary?

hkshooter
April 02, 2017, 02:38
The "grip" is held to the grip "frame" by a single screw. Inside the grip frame is the trigger "pack" which is held in by nothing more than physical perimeter barriers and the selector lever.

Are you saying the trigger "pack" is moving inside the grip "frame" or are you saying the grip "frame" is moving inside the butt stock metal?


Grip and grip frame on the right, trigger pack on the left.
https://s3.amazonaws.com/mgm-content/sites/armslist/uploads/posts/2017/02/27/6518704_03_hk_93_lower_trigger_pack_640.jpg

superjc
April 03, 2017, 20:26
Explain how the selector lever keeps the grip frame from moving.



I'll wait.

He said the "trigger pack" moves, not the grip frame.. I understand that as the box that holds the trigger inside the grip frame.... which is suspended by the selector shaft. Maybe he meant "entire fire control group" in relation to the gun?

hkshooter
April 03, 2017, 20:45
He said the "trigger pack" moves, not the grip frame.. I understand that as the box that holds the trigger inside the grip frame.... which is suspended by the selector shaft. Maybe he meant "entire fire control group" in relation to the gun?

Hard to say, he hasn't elaborated further. If one takes what he said literally it could mean one thing vs my interpretation. Maybe he'll be along at some point to clarify.

gunplumber
April 04, 2017, 10:10
Unfortunately, many people are sloppy in their nomenclature. And it can be difficult because different countries call the same thing different names, and even the same country calls it different things over time.

We have the GRIP FRAME and the TRIGGER MECHANISM HOUSING. Together, they are often/commonly called "trigger pack". But some also call the TMH "trigger pack".

If it is a factory HK 91 TMH and GRIP FRAME, the TMH can be prevented from movement within the GRIP FRAME by a shim under the welded shelf on the underside front of the TMH.

Upon first reading, I assumed the OP was referring to front to rear motion of the combined TMH and GF on the receiver.

Unless the selector hole is grossly oversize, it should not be possible for the TMH to move front to back within the GF, it could only rock around the axle of the selector.

If it it the GF moving, one must either shim the rear of the shelf on the receiver, the front of the shelf on the GF, or weld the GF where the forward of the two rear pins go.

I am wondering if it is an original grip frame and TMH.

It is also possible that there is something wrong with the travel of the ejector that is causing bolt carrier movement to transmit to the TMH.

CTG
April 04, 2017, 10:25
The "grip" is held to the grip "frame" by a single screw. Inside the grip frame is the trigger "pack" which is held in by nothing more than physical perimeter barriers and the selector lever.

Are you saying the trigger "pack" is moving inside the grip "frame" or are you saying the grip "frame" is moving inside the butt stock metal?


Grip and grip frame on the right, trigger pack on the left.
https://s3.amazonaws.com/mgm-content/sites/armslist/uploads/posts/2017/02/27/6518704_03_hk_93_lower_trigger_pack_640.jpg

Ok, fair point. Guess I should brush up on my terminology. The entire GRIP FRAME, will "click" back and forth. The trigger pack inside has given me no issues. The grip itself is solid on the grip frame.

CTG
April 04, 2017, 10:36
This right here. I know that a bit of movement is normal, but I don't like it.
And yes, it is an original '78 HK91 in its entirety.
http://i1146.photobucket.com/albums/o535/Luman77/IMG_7264_zpsyhy4cw57.jpg (http://s1146.photobucket.com/user/Luman77/media/IMG_7264_zpsyhy4cw57.jpg.html)

hkshooter
April 04, 2017, 14:02
That's the grip frame, not the trigger pack. See above for potential fixes.

superjc
April 06, 2017, 20:35
I can see how someone would use the term "trigger pack" to describe the whole assembly of trigger box/mechanism/frame.

Have you checked to see if the rear pushpin holes are oblong/oval shaped, like the Century C91 I had in the 90's- not only did it move around it fell off the semi shelf completely after 5 rounds. What a steaming turd that episode was... :facepalm:

michael_g927
April 11, 2017, 03:55
I am curious. If every HK has this flaw, but the newer clones do not, why then is it considered that the clones are "out of spec"? Could it be possible that with modern materials and modern manufacturing, that the clones have been made consistently enough to have solved the problem?

SAFN49
April 27, 2017, 12:49
Get a G3 frame with the 2 holes.

http://i36.photobucket.com/albums/e43/djm540i/20170427_123223_zpsgvvvqlrz.jpg (http://s36.photobucket.com/user/djm540i/media/20170427_123223_zpsgvvvqlrz.jpg.html)

Klaus Von Richter
April 27, 2017, 14:08
Get a G3 frame with the 2 holes.

http://i36.photobucket.com/albums/e43/djm540i/20170427_123223_zpsgvvvqlrz.jpg (http://s36.photobucket.com/user/djm540i/media/20170427_123223_zpsgvvvqlrz.jpg.html)

Yeah, that grip frame/ lower is for a 93. I have some clipped and pinned lowers or sale in the marketplace.

hkshooter
April 27, 2017, 18:41
Yeah, that grip frame/ lower is for a 93. I have some clipped and pinned lowers or sale in the marketplace.

That pic is a random pic I took from the net to differentiate trigger pack from frame, the image isn't the OP's actual parts.

SAFN49
April 27, 2017, 18:59
Yeah, that grip frame/ lower is for a 93. I have some clipped and pinned lowers or sale in the marketplace.

Yeah, NO! It's one modified to fit a HK-21

SAFN49
April 27, 2017, 19:27
OP, buy this one, a Navy G3, and have it clipped and pinned to fit HK91

http://www.gunbroker.com/item/617253154

I did this same one for my 21.

http://i36.photobucket.com/albums/e43/djm540i/20170426_150053_zpsxapaiopp.jpg (http://s36.photobucket.com/user/djm540i/media/20170426_150053_zpsxapaiopp.jpg.html)

Klaus Von Richter
April 27, 2017, 20:04
That pic is a random pic I took from the net to differentiate trigger pack from frame, the image isn't the OP's actual parts.

Damn, I don't know how I missed that. Never mind then

Klaus Von Richter
April 27, 2017, 20:06
Yeah, NO! It's one modified to fit a HK-21

I ment the other pic not your G3 lower. That is a badass HK21 you got.

Combloc
April 27, 2017, 20:29
So I bought an HK91, and I love it so far. Makes for an excellent companion to my L1A1. But the trigger pack moves slightly, and that bugs the hell outta me. It's a tiny bit of back and forth movement, nothing side to side or up and down.
I really need to fix this. What's the best way to go about doing so?

You can't. That's nogt a "problem". It's a consequence of them trimming the third pin mounting ears off. It's perfectly normal and almost every single one imported does that. In twenty five years, that has never bothered me; it's just so negligible.

Albatross52
April 27, 2017, 22:33
Cutting the push pin ears off of a German steel trigger HOUSING and welding in a semi shelf is the ugliest crap I have ever seen, and was done for import purposes only. Looks like a truck with the bumper cut off. One of the reasons that I bought a few MKE's is the push pin lowers, besides the fact that they are built under an HK license and from a company that builds everything from small arms to artillery. The clip & pin lower housings that Wehrmacht has for sale in the marketplace are functional and make the rifle look like it was in it's original form. This shit will make your head hurt...