M*CARBO Brotherhood

Trigger bar hanging on cross-bolt safety

Hi all,

I’ve upgraded the internals of the sub2k, and I’m having some issues with a sticky trigger during the take-up. Basically when the safety is off, the trigger can sometimes stick before the wall. I threw a borescope up the magazine well to see what was happening and caught some video. It appears that the trigger bar is hanging on the cross-bolt safety. When the safety is on, the trigger is very smooth (no hanging)

Video

I’m not sure what to do. I’ve disassembled and reassembled the internals twice now, hoping maybe I had just missed something the first time. The 3rd time I open this, I want to solve the issue and make the trigger feel nice and smooth. Any tips on what I can do?

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Welcome to the Brotherhood, @PREYENiG. I assume you installed the upgraded trigger bar too. It’s a little thicker than the stock trigger bar. In the video it looks like it’s hanging up in the groove of the safety. When you pull the gun apart again, check to see how tight that fit is by sliding the bar through the groove. At the least I’d polish the trigger bar and, if needed, sand it some where it interacts with the safety.

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Thanks @phuzzy42 that was helpful. I did install the upgraded trigger bar too, so that must be it. I’ll give it a try tomorrow.

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@PREYENiG welcome to the forum

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Update on this. I opened it all up again, and as @phuzzy42 said, the mcarbo trigger bar was slightly thicker than the stock trigger bar. But I noticed something else as well. The stock trigger bar was also slightly curved as well. See below

Stock bar is on the right, mcarbo left.

So I went ahead and bent the bar slightly, to mimic the original bend. This appears to have taken care of the sticking problem. The trigger still doesn’t feel great…it’s not sticking anymore, but it’s definitely rubbing against the cross bolt safety during the takeup. But it’s good enough. I finally put the loctite on the screws, so I’m not cracking this thing open again for awhile :slight_smile:

Thanks for the help all

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Hmmm, I wouldn’t have closed it up until it was right. The trigger bar should have been absolutely flat, and it should have made a noticeable difference in how crisp the break is. Did you polish it where it interacts with the safety? Made sure the slot in the safety doesn’t have any burrs? I know it’s a little late now, but you might want to fiddle with it more if you open it again. I’m glad it’s at least functional.

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@phuzzy42 The break is very crisp after the wall, but the take up before the wall is the issue. If you squeeze the trigger to the wall, then release, the trigger would sometimes stick on the wall. The original video was me performing this action.

There’s no burrs or any issues that I can see on the safety. It just seems to be rubbing against it when it’s engaged. I didn’t polish it once I noticed the curve in the original bar… that bend is a bigger difference than the thickness.

I’m positive I didn’t bend the original trigger bar, so it must have come curved like that. My thought process was that this curve gets around the rubbing issue. When I curved my trigger bar slightly to match, it lessened the rubbing as well. I’m tempted to buy another original trigger bar for comparison. If anyone else has their original bar laying around, a picture could also confirm it.

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both the gen 1 and gen 2 were flat as a board. factory
straighten em both back out, put some white out on the trigger bar, operate it, see where its dragging and slightly clearance it a bit at a time till it sweeps freely/. easier to do it now while the locktite is still green, than when you have heated it up a few times…

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@PREYENiG

Here is the original untouched Kel-Tec trigger bar laying flat, there is a slight bend at the one end. It was only used for about 50 rounds before it was replaced with the Mcarbo Trigger Bar.

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Thanks @dave67, yep that looks the same as mine. How does the take-up feel before the wall (with safety off)? Is it smooth or does it feel a little bumpy?

@GOBLIN good idea on the white out. Maybe they started curving the bars in later revisions of gen 2 (my sub2k is pretty new). I’ve read that some of the molded parts have changed slightly over the course of the gen 2 as well.

I went ahead and ordered an extra trigger bar from Kel-Tec (as well as another safety). If this trigger bar is also curved, then I think the issue is settled that these new OEM trigger bars are curved out of the factory. I’ll know in a week or so.

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@PREYENiG

Thinking back when I had the stock trigger bar installed I do no recall any “bumpy” during any part of the trigger pull. After installing all the Mcarbo internals I did polish all contact points and after a little PTFE lube everything is much smoother than stock.

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