Bullpup triggers..

warwickben

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I'm trying to figure out a good trigger setup for a build I'm working on.
Thanks to a few members I got two normal ar triggers.

Now how do I link them . And do I use two trigger springs or just one?

I'm trying to figure out a easy to make and idiot proof setup. I really been having a hard time finding photos etc of how other guys have done it.


The best idea I've come up with is to weld a tail on both triggers.
Mill a grove on bolts sides of the "lower"
And drop a rectangle plate in it. The center would be cut out.... The tail welded on the front and rear trigger I would file a notch in it to prevent the plate from lifting up to much .

I know a bull style trigger removed a lot of the springy feeling . But hard mounting the link I would have to figure out how to get it to travel in a arc.

Any advice and ideas would be helpful.
Pictures of other triggers would help too.
 

warwickben

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i take it's an AR bullpup? any more details on overall layout? i need to visualize
Doing a clone of the magpul pdr. That was never built .

A member printed out a scale print for me . As it sits now it will be 1.5 inches longer in the butt stock then the pdr reported 18 inch over all length . I'm going to def be wider then what they claimed . If I could afford to send a square bolt body out to have a ar cam pin grove milled in it I could make it thinner and just use a ak or kel tec piston recoil spring set up.

My "upper" started as a 1.5 rd aluminum bar stock .
Bored then reamed to ar spec .
Bottom side milled out to ar specs so I could be lazy and not figure that Info out. Also fly cut the bottom so center line matches a normal ar specs .

Top side has a .415 slot milled down the center for the gas key to ride in.
Turned 1 1/4 x18 thread on the front for a standard ar nut with the locating pin slot.
Sides will be fly cut to thin the width down.
I need to get a measurement of a standard barrel nut Including the gas tube tabs.
I'll probably flute the upper to remove weight .

Bolt is going to be a ar bolt chopped little behind the firing pin . Special block /gas key mounted on top of the receiver that ar180 recoil springs will act on .

Lower will be made out of some plastic etc . Need to figure out what would not melt......


What else you want to know ?
 

Wildweasel

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As to the 2 trigger springs Maybe. On one of my builds (sten) with the ar trigger connected to the stock trigger by a bar it is very sensitive . (the trigger resets and the sear works so not a true doubling, but it acts like a bumpfire unless you are careful to get the finger off the trigger. ) I will be adding a 2nd ar trigger spring the the back trigger. (I did it that way with the K and it still has a nice trigger feel)

As to linkage on the Bushy I had (M-17) it is heavily supported in the stock (there is a groove for the rod that was used for the trigger extension, and it worked well if you had the whole thing in a nice layer of grease.
 

warwickben

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As to the 2 trigger springs Maybe. On one of my builds (sten) with the ar trigger connected to the stock trigger by a bar it is very sensitive . (the trigger resets and the sear works so not a true doubling, but it acts like a bumpfire unless you are careful to get the finger off the trigger. ) I will be adding a 2nd ar trigger spring the the back trigger. (I did it that way with the K and it still has a nice trigger feel)

As to linkage on the Bushy I had (M-17) it is heavily supported in the stock (there is a groove for the rod that was used for the trigger extension, and it worked well if you had the whole thing in a nice layer of grease.
I was thinking clipping one leg on each trigger spring .
Figure try it with both springs . 1 spring . Two clipped springs etc.
 

Boris

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first and the foremost issue with any trigger design is to make sure that it is not "easily convertable to mg" per ATF. There are a lot of options for good triggers, but making it both ATF-pleasing and workable is the real challenge.
 

7.62x39

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I thought about your set up .
How dose it not flex ?
Posts 4 & 9 in that thread show it best.
The biggest issue with the factory connector is the two doglegs where the connector runs parallel to the axis pins. Eliminating both of those, going to the heavier gauge wire and adding the turnbuckle to take up the slack that is necessary to install the connector, takes care of all the flex problems associated with the factory set up.

Edit to add. One other thing that helped out was adding the little arm to the disconnector which gave it more leverage therefore requiring less trigger pull than the factory set up, putting less strain on the connector.
 
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warwickben

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first and the foremost issue with any trigger design is to make sure that it is not "easily convertable to mg" per ATF. There are a lot of options for good triggers, but making it both ATF-pleasing and workable is the real challenge.
That's why I was going to use a ar trigger . I figure since there's no way to trip the auto sear since I'm cutting the bolt in half.And Not milling out the rear section I should be ok.

I'm to small and pretty to go to jail I'll be some ones bitch lol .
 
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i've been searching for a good simple design for AK bullpup trigger config myself. i don't think i'm that fond of a wire and buckle though. Has anyone seen any other designs?
 

Boris

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i've been searching for a good simple design for AK bullpup trigger config myself. i don't think i'm that fond of a wire and buckle though. Has anyone seen any other designs?
you have [laugh] Russians like to push (гроза)

[video=youtube_share;vCadcBR95oU]http://youtu.be/vCadcBR95oU[/video]
 

Boris

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they had to do push because of under-barrel grenade launcher that's operated by same trigger. have you come up with anything yourself in the past few weeks that we weren't discussing our bullpup projects?
Russian comrades have to do nothing. Pushing is superior. ATF approval is kind of crucial for any ideas.
 

warwickben

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I was thinking of doing a ak build at one point.

My idea was to cut a tube down the center and spot weld it to the sides of the reciver.

Cut a slot on both sides.
Run two bars in side the and have a pin on each end linking the bars and the triggers.

If you making your own receiver and have a bead roller you could allways do that to get the linkage around the trunnion.
 

7.62x39

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i don't think i'm that fond of a wire and buckle though.
As far as fitting within the confines of a normal receiver go, you are pretty much limited to this. There is very little space to work with.
I thought about going outside like warwickben mentioned, but the scope of the project was to come up with a solution that the average home builder could accomplish.
 

warwickben

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I've seen some people cut groves Into the sides of the trunnion to sneak it a around that way.
Just not sure how much you can remove and still be safe .
 

7.62x39

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The trunnion is one obstacle for sure, but the mag dimple and hammer pins are two more. Unless you remove the mag dimple, you must go under it and it's a tight squeeze. After you go under the hammer axis pin you must angle up sharply to be high enough to have any leverage on the slave trigger. I had envisioned using some sort of a bell crank there, but there just isn't enough room.
 
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