AK trigger job

[Jtgarner]

Okay guys, so here is the story:
I have a draco that I am waiting to SBR (damn its only been like 25 days and I am going crazy) so I tinker with it almost every day. I have already JB welded a bent washer onto the safety to enable myself to use it without taking my hand off the grip (eventually will be a krebs, but for now its a poor man's krebs). I also have a bart break on it (with an oring to keep it from wiggling). I got a G2 trigger kit at the 1500 and installed it the next day. The trigger pull was good, but the bolt dragged pretty bad, and frankly I just didn't like that. After talking about it on here with a few members I realized that the reason the tapco caused bolt drag and the stock trigger didn't was because the tapco let the hammer ride too high. I decided that I was going to swap back in the stock trigger after doing some work on it and see if I could make it as good, if not better, than the tapco. I left the hammer and disconnecter from the G2, but put back in the stock trigger. I filed down the part that the hammer catches on at a slight angle and polished that part, I also polished the hammer where the hook catches. This brings the pull weight down to better than the G2, but there is a lot of both pre and post travel.

My idea (and that is as far as it has gotten so far) is to install 2 set screws on the underside of both the front and back of the trigger (like 28 and 42).

This would allow me to adjust the pre and post travel of the trigger a little at a time until it is exactly how I want it. (I guess I did too many paintball trigger jobs in my day)

My question is do I have to use a set screw that is smaller in diameter then the trigger part is wide? I feel like the screw would be more durable if it was thicker, but tapping a hole that is wider than the trigger part might compromise the structural integrity of the trigger.

My problem is that I am a student here in the "great" city of Bloomington and so I don't have the ability to drill and tap. If anyone near bloomington reads this and has the tools I would buy you a beer to show/teach me how to use them to do this.

Not much worry if I mess it up since I have the G2 trigger, but I would like to get it right, cause this trigger pull is sweet.

 

[the1kidd03]

a general rule of thumb in engineering is to have at least 1/2 the diameter of the bolt/screw worth of material all around the whole you create for it.....set screws are pretty tough anyway.....the thing you should think about is how/where other parts will be rubbing/beating up on the exposed portion of that set screw.....causing the head to wear/mushroom out the opening for your wrench and you won't be able to adjust and possibly even remove it without additional specialized tooling

I have the equipment/tooling necessary...but I'm in Indy

 

[the1kidd03]

you may also wish to think about if it is better/easier to modify the g2 trigger to function more like the stock trigger

 

[Jtgarner]

a general rule of thumb in engineering is to have at least 1/2 the diameter of the bolt/screw worth of material all around the whole you create for it.....set screws are pretty tough anyway.....the thing you should think about is how/where other parts will be rubbing/beating up on the exposed portion of that set screw.....causing the head to wear/mushroom out the opening for your wrench and you won't be able to adjust and possibly even remove it without additional specialized tooling

I have the equipment/tooling necessary...but I'm in Indy

Good rule to know. I don't think there really is anything to wear on the set screw, as it would just set up against the bottom of the receiver. I have thought about using a regular screw with a round top and a flat head opening, but who knows.

you may also wish to think about if it is better/easier to modify the g2 trigger to function more like the stock trigger

Without adding material to the G2 that would not help me at all, as I would be back at the problem of bolt drag.

 

[the1kidd03]

I would add the material personally, but I have access to the equipment I need to do it too.......the other thing you'll want to consider is the set screw will work itself loose and adjustment will offset through repeated use.......I guess a cheap fix for this would be BLUE loctite though

 

[the1kidd03]

wow...I just realized I typed "whole" instead of "hole".....I'm brain dead tonight

 

[Jtgarner]

Yeah I was planning on some blue loctite for sure, once I put a few hundred rounds through it I would expect the wear to stop and I might even be able to use red loctite (probably still stick with blue though so I can always adjust the trigger however I like).

And I can't even drill and tap holes on my own, so adding material to the G2 is pretty far out of the question.

I am pretty set on what I want to do, I just need to find someone to help me do it, and maybe see if anyone has any more suggestions.

(and you can edit your posts after posting, no need to inflate your post count by posting twice in a row)

 

[the1kidd03]

eh...I don't care about post count

I would refrain from red loctite...it's not meant to be removed....in my experience it takes a torch to remove bolts with red....blue will still work...just take out the screw, clean it up or replace it and put a dab more blue on it

 

[MattCFII]

Note that some people say that 922r applies so you might want to get a US trigger group anyway.

Red Star Arms makes a adjustable trigger (which may be the figure).
Red Star Arms Inc.

Also bolt drag gets less the more you use a G2. It doesn't normally effect function anyway, in fact it is nice on ranges to hold the bolt open.

 

[Jtgarner]

Note that some people say that 922r applies so you might want to get a US trigger group anyway.

Red Star Arms makes a adjustable trigger (which may be the figure).
Red Star Arms Inc.

Also bolt drag gets less the more you use a G2. It doesn't normally effect function anyway, in fact it is nice on ranges to hold the bolt open.

I'm not worried about 922r right now. With the G2 I would have enough compliance parts, so if I just take the trigger out and still use the hammer and disconecter, that would only put me down one part and would therefore give me an excuse to get a new handguard set

And I have heard that the bolt drag will work its self out, but if I could make a better trigger that doesn't allow so much bolt drag I'm gonna try it first.

Thanks for the thoughts guys, keep em coming.
I still need someone with the tools to show/help/teach me how to do this.

 

[MattCFII]

I'm not worried about 922r right now. With the G2 I would have enough compliance parts, so if I just take the trigger out and still use the hammer and disconecter, that would only put me down one part and would therefore give me an excuse to get a new handguard set

And I have heard that the bolt drag will work its self out, but if I could make a better trigger that doesn't allow so much bolt drag I'm gonna try it first.

Thanks for the thoughts guys, keep em coming.
I still need someone with the tools to show/help/teach me how to do this.

I know 922r isn't a problem right now on a Draco, but just throwing it out there if you do all this work to a trigger group and then you can't use it later...

 

[Jtgarner]

I know, and that is a valid point, but since the paperwork for my SBR probably wont be back until January, and I already have a Us made grip, muzzle device, hammer, disconecter, and buttstock (ready to drill and tap when paperwork gets here), I would only need one more part for compliance (if I use the stock trigger) so I could get a handguard or even a us made gas piston to fix that before the stamp gets here.

Edit: at least I think I would have all the compliance parts needed... my sources say I only need 6 parts.

 

[tnek]

Note that some people say that 922r applies so you might want to get a US trigger group anyway.

Red Star Arms makes a adjustable trigger (which may be the figure).
Red Star Arms Inc.

Also bolt drag gets less the more you use a G2. It doesn't normally effect function anyway, in fact it is nice on ranges to hold the bolt open.

YES!!!
I have a Red Star arms trigger in my Saiga and it is great. Take up and overtravel are nil. Breaks clean at about 2 pounds. For your time and trouble it's well worth the money.

 

[MattCFII]

I know, and that is a valid point, but since the paperwork for my SBR probably wont be back until January, and I already have a Us made grip, muzzle device, hammer, disconecter, and buttstock (ready to drill and tap when paperwork gets here), I would only need one more part for compliance (if I use the stock trigger) so I could get a handguard or even a us made gas piston to fix that before the stamp gets here.

Edit: at least I think I would have all the compliance parts needed... my sources say I only need 6 parts.

Yep, 6 would be he number with a muzzle device. Don't forget maybe US Palm mags which would count as 3 and/or K-Var's US floorplates and followers.

 

[the1kidd03]

If you can tell me how thick the metal is I can give you detailed instructions what to do and how to with some basic, relatively cheap tools you can pick up at Lowes....at least then (if you do have to buy a couple) you will have them for any future endeavors...most hand held tools/equipment pay for themselves the first time you use them...(i.e. how much would you have to pay someone to do the work FOR you rather than buying the tool ONCE and be able to use it forever)

List of some basics you'll need to get you hands on:
a sturdy table to work at
vise grips (fairly good size/large)
a C-clamp big enough to clamp the vise grips to your table...probably 6" clamp....or those "Irwin" slide-pressure clamps would work too
a starter/center punch....a pointed scribe could work too
a drill (battery, air, cordless...NOT an "electric screwdriver")
....the rest of the tools I'll list once you let me know the thickness of the metal you're drilling

 

[Jtgarner]

Matt, I don't want to have to count on mags for compliance parts. I plan to put a Ultimak rail on it, so that would cover the one part I still need. If I had to I could get a us gas piston, but I will probably have enough saved for the rail before the stamp comes back so I'm not worried.

I believe you guys that the red star trigger is great, but if I can get the same idea out of what I have and learn a little skill in the process I would rather do it that way... plus then it is completely custom.

the1kid, I can try to get some measurements tonight, as I will probably have to buy the tap and screws after I find someone to help me do it anyway, but I don't want to get too many tools. I have access to a few great shops (personal) at home that would have everything I need, but since I am in B-town for school I can't utilize them. I was hoping someone near bloomington would see this and offer to let me use their tools and maybe show me how to do this.
vitamink might be able to help me, but he is in Indy and he has already told me he would help me drill and tap my draco when the stamp comes in.

 

[Calvin]

I have messed with many AK triggers, and own 2 of the RSA adjustable triggers. My last few rifles have settled me on using G2 triggers as my base, but adding a blob of weld into the area of set screws 42 and 28. Make the blobs larger than needed, and then file down while test fitting repeatedly until it is just right. Carefully file the contacting surfaces on the hammer, disconnector, and sear. Pay particular attention to get the surfaces where the sear grabs the hammer to be as perfectly parallel to each other as possible. This will smooth the trigger and make much less wear on the parts over time. I then look at how long the travel is before release of the hammer, and put a nice crisp 90 degree surface on the front of the sear hook to create a crisp release with enough pre travel to keep it safe. Finish by chucking the pins into the drill press and 0000 steel wooling them followed by a gentle dremel polishing of all of the stoned surfaces. Clean all the parts completely with a solvent (to get rid of the polishing compound), lube them, and reassemble. The resulting triggers have been very smooth, with a crisp and predictable letoff. The are solid state in that there will be no movement of the set screws and the welds are wide enough they will not be wearing down. I do not find changing the disconnector by adding screw #20 to be that useful. The pull is lightened by reducing the friction throughout the system. I have found it to be neither necessary nor desireable to lighten the pull further in such a rifle. While you are there with the files and stones, take some time to smooth the machining marks and round the edges on the bottom of the bolt carrier where it meets the hammer as well as the matching upper hammer surface. It slicks up the action and aids reliability. The total of all of these activities should be about 2 hours depending on how OCD you are and how good your tools are.

 

[Jtgarner]

I have messed with many AK triggers, and own 2 of the RSA adjustable triggers. My last few rifles have settled me on using G2 triggers as my base, but adding a blob of weld into the area of set screws 42 and 28. Make the blobs larger than needed, and then file down while test fitting repeatedly until it is just right. Carefully file the contacting surfaces on the hammer, disconnector, and sear. Pay particular attention to get the surfaces where the sear grabs the hammer to be as perfectly parallel to each other as possible. This will smooth the trigger and make much less wear on the parts over time. I then look at how long the travel is before release of the hammer, and put a nice crisp 90 degree surface on the front of the sear hook to create a crisp release with enough pre travel to keep it safe. Finish by chucking the pins into the drill press and 0000 steel wooling them followed by a gentle dremel polishing of all of the stoned surfaces. Clean all the parts completely with a solvent (to get rid of the polishing compound), lube them, and reassemble. The resulting triggers have been very smooth, with a crisp and predictable letoff. The are solid state in that there will be no movement of the set screws and the welds are wide enough they will not be wearing down. I do not find changing the disconnector by adding screw #20 to be that useful. The pull is lightened by reducing the friction throughout the system. I have found it to be neither necessary nor desireable to lighten the pull further in such a rifle. While you are there with the files and stones, take some time to smooth the machining marks and round the edges on the bottom of the bolt carrier where it meets the hammer as well as the matching upper hammer surface. It slicks up the action and aids reliability. The total of all of these activities should be about 2 hours depending on how OCD you are and how good your tools are.

This is a great idea! I had actually just talked to btgarner0 (my dad) about putting a drop of weld on there in place of the set screw and filing it down like you mentioned. I think that would be a little easier than doing the drilling and taping, but I would not have the ability to change it as easily later if I wanted to. Still a good idea though, and a possibility given that I can't find anyone with the tools here in bloomington to help me drill and tap. I did a little filing and polishing of the parts when I had it apart, but I will go back and hit some of the other parts you mentioned too!
Thanks for the input.

Calvin, I see you are in bloomington too, do you have the stuff at your house available to add the welds (or even to drill and tap it)? I would buy you a beer or something if you would help me out with it sometime. Let me know

 

[Jtgarner]

Update: with the help of Calvin I decided to go with welds that I can file down to set up the trigger how I like. I'll post pics when I get it back and all set up.

 

[Jtgarner]

No pics just yet, but I got the trigger back tonight and did just enough filing to get it to function in the gun. My biggest problem is that I want very little over-travel, but I want it to be safe. Right now the hammer clears the sear and just barely hooks on the disconnecter. I am probably going to file a little more so I get a little more contact on the disconnecter and hammer. The pre travel is pretty short right now, and I like it, but I might file a little more off of that too just so there is a little play before the break so it is a little safer.
I took some pictures after I had just started filing, so you can see what the before looked like, but I will wait to post those until I get the trigger how I want and get some after pictures.