WTB: four position fire control group parts

[J. McF]

Hello, I am trying to locate the last three parts needed to complete a 4 position FCG, any brand will be fine. I’m even fine buying reproduced parts if you or someone you has the ability to manufacture the parts I need….I am only needing the four position specific auto sear…and both the right and left four positions specific disconnectors. Just those three parts. Any help would be greatly appreciated!! Thanks!!! -J

 

Edited October 22, 2021 by J. McF
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[J. McF]

17 minutes ago, J. McF said:

Hello, I am trying to locate the last three parts needed to complete a 4 position FCG, any brand will be fine. I’m even fine buying reproduced parts if you or someone you has the ability to manufacture the parts I need….I am only needing the four position specific auto sear…and both the right and left four positions specific disconnectors. Just those three parts. Any help would be greatly appreciated!! Thanks!!! -J

https://share.icloud.com/photos/09GiPS53VGek1DcjarxzPIkAw

[SPaulS]

I too would love to get my hands on a colt 4 way sear, with the big hook. Don't understand the design, can only speculate colt was required? to keep semi in the 12 o'clock position. DPMS 4 way pattern makes more sence if you ask me. First flip is auto or burst and then semi, just don't forget to hold down the sniper button on the right side for those semi sniper shots .

I am working on some dpms style 4 way kits. Milled ambi selector with screw on pointer caps sized to fit over the receiver stops. Eventually be 3 round kits with welded and modified parts.

Anyways J.Mcf, what kind of build are you doing? Colt original looking setup with engraved FCG markings or slapping parts into what you have?

As for the colt 4 way sear being rare and hard to find. In a pinch I wonder if a standard sear could be slightly modified or cut to work. Maybe enough so that the sear will always catch the hammer but enough tail left so it won't do a backwards 180. Would be just like a RDIAS setup.

Edited October 28, 2021 by SPaulS

[hkg3k]

On 10/22/2021 at 4:09 AM, J. McF said:

Hello, I am trying to locate the last three parts needed to complete a 4 position FCG, any brand will be fine. I’m even fine buying reproduced parts if you or someone you has the ability to manufacture the parts I need….I am only needing the four position specific auto sear…and both the right and left four positions specific disconnectors. Just those three parts. Any help would be greatly appreciated!! Thanks!

 

I've had probably (10) 4-position kits over the years, both DPMS and Colt.  When the prices got insane, I sold them all except for a couple of Colt kits.  I currently run a couple Colt 4-position kits with a couple of my RDIAS.  The 4-position autosears are not required for my setup and I sold off those off as individual pieces as well.

The left (single hook) disconnector you're looking for is easy.  Just use the disconnector from a 3-rd burst kit.  The tail on the single hook burst disconnector is bent to fall in the center of the trigger valley.  You can take that disconnector and hammer the tail flat...so that it and the correct 2-hook disconnector with tail will both fit and move, side by side, in the trigger.  Use the Colt left disconnector, as the other (cheaper) cast left disconnectors out there will tail-break as soon as you hit them with a hammer a couple times.

Your rainbow unicorn of these parts is going to be the right (double hook with tail) disconnector...you'd probably have more success taking a burst double-hook disconnector to a machinist to weld on a piece and then profile the tail.

Good luck.

Edited October 28, 2021 by hkg3k

[SPaulS]

I too run one of my 4 position kit with a RDIAS like hkg3k. I would say both DPMS or Colt selector with a RDIAS is good to go.

For me out of all the parts between the two kits the Colt sear is the unicorn. Unlike the DPMS sear, which is just a cut down sear, the Colt has its hook. The problem is there is no easy way to reproduce one short of stamping new sheet metal. I have never had one but it looks thin to weld and tough to match the original shape.  I don't think a standard sear could be cut to match because the colt selector doesn't use quadrants in line to the markings, with the hook end going past 90 degrees of the selector. see the pictures if that makes sense.

With a Colt selector, unless you have a RDIAS or a Colt sear I am not sure how to make it work. Something needs to limit the rotation of the sear so it moves enough to catch the hammer but not do a full spin. So I don't think just cutting the leg of a sear would work.

Like hkg3k said hammering out and welding a tail on the burst disconnector is simple enough. Just make sure the two disconnectors don't rub each other and that the disconnectors don't catch the hammer when they shouldn't. 

Eventually I'll have a few 4 position kits for sale. They will be DPMS pattern custom ambi selectors, welded burst disconnector tails and the rest from 3rd burst kits. But even with disconnectors the Colt selector will be hard to get working without a colt sear so I couldn't help with that.

Edited October 29, 2021 by SPaulS
stupid pictures

[hkg3k]

10 hours ago, SPaulS said:

For me out of all the parts between the two kits the Colt sear is the unicorn.

You're probably correct as discussed today...and in the context of difficulty of reproducing the Colt autosear -or- creating a work-around.  I was thinking in the past when the right side double hook disconnector was the piece in which availability dried up 1st, while Colt autosears were still available from different sources for some time.  Colt selectors seem to be the last to dry up and I still see them pop up from time to time.

Good luck on making the DPMS pattern parts.  I too always liked the fact the DPMS selector clears the stops and moves to either F/A or Burst from Safe...and Semi was 180* from Safe.  That makes more sense for us hobbyists who spend most of the time shooting their machine guns in burst or full auto. 

However, Colt is Colt and the reason I settled with that configuration on a couple custom lowers I specifically set up for RDIAS'.

Edited October 29, 2021 by hkg3k

[Devildog502]

On 10/29/2021 at 0:32 AM, SPaulS said:

I too run one of my 4 position kit with a RDIAS like hkg3k. I would say both DPMS or Colt selector with a RDIAS is good to go.

For me out of all the parts between the two kits the Colt sear is the unicorn. Unlike the DPMS sear, which is just a cut down sear, the Colt has its hook. The problem is there is no easy way to reproduce one short of stamping new sheet metal. I have never had one but it looks thin to weld and tough to match the original shape.  I don't think a standard sear could be cut to match because the colt selector doesn't use quadrants in line to the markings, with the hook end going past 90 degrees of the selector. see the pictures if that makes sense.

With a Colt selector, unless you have a RDIAS or a Colt sear I am not sure how to make it work. Something needs to limit the rotation of the sear so it moves enough to catch the hammer but not do a full spin. So I don't think just cutting the leg of a sear would work.

Like hkg3k said hammering out and welding a tail on the burst disconnector is simple enough. Just make sure the two disconnectors don't rub each other and that the disconnectors don't catch the hammer when they shouldn't. 

Eventually I'll have a few 4 position kits for sale. They will be DPMS pattern custom ambi selectors, welded burst disconnector tails and the rest from 3rd burst kits. But even with disconnectors the Colt selector will be hard to get working without a colt sear so I couldn't help with that.

Did you ever get those kits done, I need the double hooked right disconnect I have a couple colt selectors