[wildweasel]

Problem resolved, Soulution at end of posts. (excessive wear on trigger caused by an incorrectly bent sear spring)
First off I do have an email in to Tom , and this is in no way a flame or gripe about the Karma trigger.

I have one of the older (bought last Jan from 30 cal Machinegunner here as part of my package deal with the semi machining he did for me. ) trigger, been working fine I have maybe 1K rounds through it over the last year. went to a shoot yesterday and was shooting 8mm (romy) and the trigger was getting hard to pull (almost impossible to rapid fire,)

when I broke it down and cleaned it I discovered quite a lot of movement between the upper bar (the part that engages the sear) and the lower trigger. almost 1/8" at one end. this makes for a very hard to operate gun.

Has anyone seen this? fixes? I do have a TIG and can weld it but won't till I hear back from karma.

Thanks

 

[fal_762x51]

Tom will probably replace it, he's a good guy.

 

[30calmachinegunner]

Yep, I am betting the bar that is machined on the top of the trigger that the disconnector slides on is broken. To check it out pull the disconnector forward and just before it reaches maximum travel the little cross pin can be pushed out, nothing should be forced. Pull the disconnector off and i bet the the top bar of the slot is broken.

By the way I still have one of the trigger that is wide on the pad and narrow for the slot, I will also open up the slot for free for the new wider trigger if you want, good luck, Brian.

 

[tomt]

kmp trigger

sounds like something did break / crack. do what 30 told ya and let me know. if itneeds replaced, we'll take care of it. thanks. tomt

 

[MrBi11]

I will also open up the slot for free for the new wider trigger if you want, good luck, Brian.

I'm continued to be amazed with your overwhelming desire to make people happy, well beyond normal business practices. It's people like You and Tom that make me glad to recomend your services to everyone.

I just felt I needed to add my 2¢

 

[wildweasel]

Thanks for the Kind offer Brian, I can do the machining,
I just pulled the trigger apart and it is not broken I just think it has some wear on all surfaces causing the slop.

The front edge of the lower trigger is worn down causing the problem I think. How much movement is normal? The further out you pull it the worse the movement becomes. (when it is locked up in the receiver it is pronounced.)


(good thing I didn't weld it LOL) Thanks for the help, You guys are great.
(and your machine work will be hard to beat Brian but I will try to do my next one myself. )
(I do run the gun wet with lube so that shouldn't be the issue.) I did try adjusting the trigger return plunger setup too. helps some but I was having problems putting the rear grip back on with it up too far. )

I can email pics if you want also.

 

[30calmachinegunner]

If I am thinking correctly the disconnector only needs to move front to back about 1/8" and should be all or most of the way toward the back to engage the sear, it should never need to go anywhere near so far forward as to what it takes to take it apart. If there is minimal play when the disconnector is in the rearward position it should work.

I hate to say it but are sure there is not a small fracture in the slot the pin fits in, I have had to take a couple looks at them sometimes to notice it, just a thought.

By the way the steel inserts in the lock frame are silver soldered in place.

 

[tomt]

kmp

mr bi11, that was very nice of you. i'm sure brian appreciates it, as do i. thank you. wild. the trig should not have any wear, the disconnector only should move about .060 when in the correct position ( thats all it needs to go back and forth) when it is properly assembled there should be no gap at the front. if you get the pin in wrong, or hyper-extend it, it could jam. the pins flat has to be dead north. if you have it right it will show no gap in the front. hope this helps. call if any ? thanks. tomt

 

[wildweasel]

Tom I will give you a call today sometime. It definatly sounds like there is an issue with my trigger. I need to order another set for gun #2 anyway so I will be in touch.
Glenn

 

[wildweasel]

Just a quick follow up Tom fixed the trigger and suggested I check the fit of the sear to the bolt (possibly tight) which I will. (I was wondering if that was a possible issue .) Thanks and I just recently bought another KMP trigger set for my next gun.

 

[30calmachinegunner]

Well I hope it is not tight, I try to machine them close and occasionally they may need a couple swipes with a stone, please let me know.

 

[wildweasel]

Well I hope it is not tight, I try to machine them close and occasionally they may need a couple swipes with a stone, please let me know.

NO worries Brian I just checked it and it slides like Butter. So I don't think that is the issue. It developed in the last 300 rounds. (hard trigger lots of travel due to the trigger being loose. ) Evan under a side load it moves freely. I Don't know what to say but thanks to both of you for following up on your work. Makes me happy to be a member here.

Just to put this to bed, Tom was more or less right, while it wasn't the sear or slot that 30 cal machined it was the sear spring. it was bent twice as high as my NOS spare. I also compared the firing pin to my spare and noticed the catch area was quite rough on the original. I lightly stoned it with my fine stone (being careful not to change the angle of the engagement area (just enough to take the finish off both it and the sear evenly.) it now engages cleanly and releases like it should have. I reassembled the gun and the trigger is much better. (not a target trigger but I know they aren't that!)

so in conclusion It was likely the hyper extended sear spring(it was that way when I got the kit and I had nothing to compare it to) that caused the premature wear on the trigger that Tom so nicely fixed for me under warranty. Thanks guys for the great support.

 

[loboslanding]

Sometimes guys will inadvertently install the sear spring with the arms laying on top of the sear in lieu of in the slot at the top of the sear and that will bend the arms up which when properly installed can put too much upward tension on the sear. Some poor GI probably did that with youir spring before you ever got it. You can bend the arms back into place and reuse it.

 

[tomt]

trig

glad you figured it out.the pin wore the hell out of the disconnector.must have been an awfull lot of pressure. tomt

 

[wildweasel]

The top of the spring was twice as high as my other one in the bolt. took a lot of pressure to bend it back but I did. It really helped to have my spare kit (didn't when the problem developed) to troubleshoot the problem. that and I really took the time to figure out exactly how you made the trigger and sear semi auto! Very clever.

 

[tomt]

trig

wish i could takethe credit for that. but i can't. i just refined it. i think tim bero did the original. gotta give credit wher credit is due. !! thanks. tomt