[Chowwow]

Not sure why you chose to call me out specifically, but hey, whatever. You basically invited the following response by singling me out, so here it is:

Don't get me wrong, I didn't intent to call you out for anything, your name was the most recognizable that jumped out of my head and the old members of the forum are sure to drop their two cents on most of the topics around here. I knew people would rag on me for an obvious mistake and I just intend to be aware of my shortcomings and limitations.

You don't own an AR lower that you can cross measure to see the pin difference?.....which makes me wonder if you've actually shot one.

I have shot an M&P-15 but I obviously don't own one, otherwise I wouldn't have gotten so excited about jury-rigging a AR binary trigger into the XCR so soon. I don't intend to own more guns than I have fingers on one hand, and I've never been all that interested in the AR-15 other than a few components and its low cost. It was worth a rental on a range but not much more. It is why I settled on the XCR for its versatility and construction. It's still worth a close look.

Do you actually have access to the CNC equipment to do so?

If you must know about my boring backstory, I am in school to be a CNC machinist and I'm looking to start my apprenticeship real soon with local machine shops. That's why a lot of my solutions revolve use of CNC machines. So for the time being, I do have access to CNC machines that I have a reasonable level of competency and freedom with (reasonable as in not crashing while I operate them and freedom as in not making NFA items out of facilities not licensed for them). Might get tricky to be around one once I'm out of the school's machine shop.

I'm looking to get into making guns that are interesting to me, hence the study into the XCR binary trigger. However, if I don't find an easy solution to it then the idea will have to go in the back burner while I execute more low-hanging projects. Getting the dimensions to get the right timing on a trigger system is not something I've worked on ever. Adding an unreliable gimmick to a rifle that works fine semi-auto also makes this idea less of a priority. Still, I am interested in playing with the AR binary trigger, both in a FGC-9 build I want to do and, after learning from that, a specialized pistol.

 

[Sean K.]

Don't get me wrong, I didn't intent to call you out for anything, you're name was the most recognizable that jumped out of my head and the old members of the forum are sure to drop their two cents on most of the topics around here. I knew people would rag on me for an obvious mistake and I just intend to be aware of my shortcomings and limitations.


I obviously don't, otherwise I wouldn't have gotten so excited about jury-rigging a AR binary trigger into the XCR so soon. I don't intend to own more guns than I have fingers on one hand, and I've never been all that interested in the AR-15 other than a few components and it's low cost. It was worth a rental on a range but not much more. It is why I settled on the XCR for its versatility and construction. It's still worth a close look.


If you must know about my boring backstory, I am in school to be a CNC machinist and I'm looking to start my apprenticeship real soon with local machine shops. That's why a lot of my solutions revolve use of CNC machines. So for the time being, I do have access to CNC machines that I have a reasonable level of competency and freedom with (reasonable as in not crashing while I operate them and freedom as in not making NFA items out of facilities not licensed for them). Might get tricky to be around one once I'm out of the school's machine shop.

I'm looking to get into making guns that are interesting to me, hence the study into the XCR binary trigger. However, if I don't find an easy solution to it then the idea will have to go in the back burner while I execute more low-hanging projects. Getting the dimensions to get the right timing on a trigger system is not something I've worked on ever. Adding an unreliable gimmick to a rifle that works fine semi-auto also makes this idea less of a priority. Still, I am interested in playing with the AR binary trigger, both in a FGC-9 build I want to do and, after learning from that, a specialized pistol.

Didn't mean to pry....but needed a frame of reference.

JFYI, I've modded a LOT of triggers over the years....the factory XCR trigger is actually really pretty darn good. It could benefit from a polish job to make it smoother (or you can just let it wear in more) and I think the disconnector could have material added to it to make the reset travel in particular much shorter. I bought a spare disco to do exactly that...just haven't had time nor have I fired up the TIG.

If I still had CNC access, I'd cad up a new disco entirely as that's the better way to go versus welding....but you work with what you have.

I wish you much success and hope you can figure out how to make the semi auto part of a binary an excellent trigger. Just adding binary capability and leaving a shit trigger, to me is pointless other than for grins.....but I'm an admitted trigger snob. Once you have a really good trigger in a gun, you'll never compromise and want to go backwards, even for binary.

 

[Chowwow]

If I still had CNC access, I'd cad up a new disco entirely as that's the better way to go versus welding....but you work with what you have.

Still? You don't work in a place with CNCs anymore?

Also, what steel are triggers typically made from? There are desktop CNC machines that I can get for relatively cheap that mainly cut aluminum, but I don't know if I can rig one to machine 4140 alloy or anything tougher than high speed steel.

I figure making a binary trigger in the XCR is a decent enough idea in a time when machine guns are banned (I don't think even Robinson has an auto sear for it). Even so, I feel like the Binary Trigger is best suited for a cheaper platform in addition to your other arsenal and not your main rifle. I'd like to install one in the FGC-9 as a burst-fire PCC, then later into a compact burst-fire pistol; I'd get my money's worth in such applications.

 

[Sean K.]

Still? You don't work in a place with CNCs anymore?

Also, what steel are triggers typically made from? There are desktop CNC machines that I can get for relatively cheap that mainly cut aluminum, but I don't know if I can rig one to machine 4140 alloy or anything tougher than high speed steel.

I figure making a binary trigger in the XCR is a decent enough idea in a time when machine guns are banned (I don't think even Robinson has an auto sear for it). Even so, I feel like the Binary Trigger is best suited for a cheaper platform in addition to your other arsenal and not your main rifle. I'd like to install one in the FGC-9 as a burst-fire PCC, then later into a compact burst-fire pistol; I'd get my money's worth in such applications.

Nope. We farm out most of our CNC work here. We have manual mills and lathes for prototyping but I'm not a skilled machinist....just a hobbyist at best.

RA has auto sears....they used to be (dont' know a current status) a SOT.

 

[Hartman23Foscari]

Interesting idea, actually. You think the dimensions on the upper would change much if they serialized it? Are we on the 3rd revision of the XCR right now? Maybe the next revision they could serialize both the upper and lower, so that if you don't get a complete rifle from RA, you could build around it with their parts. A shorter lower ought to be an advantage for some AR-15 builders, and having unified uppers are a premium AR product - it's sure to be competitive when LMT has got it hands busy.


Fascinating. With luck, it's possible that all you would need to do is CNC machine a hammer that's compatible with the XCR and drop it into the binary trigger. I really need to examine a binary trigger though, because I don't know if there is something about the hammer in it that helps with the binary fire function. I think I'll get one just to examine when my budget is able to breathe.

something that would be truly interesting to see, if they wanted to go with a shorter lower. They should make the step striker fired, ala vz58. the vz58 is lighter then a stamped ak yet is milled because its lighter weight. It would allow them to make a truly short system since the striker does all the work and the trigger just releases it.

hell ive had the idea for somehow taking a vz58 style lower with an ar style upper with a piston driven system. Would be the ultimate gun advancement imho.

 

[Sean K.]

something that would be truly interesting to see, if they wanted to go with a shorter lower. They should make the step striker fired, ala vz58. the vz58 is lighter then a stamped ak yet is milled because its lighter weight. It would allow them to make a truly short system since the striker does all the work and the trigger just releases it.

hell ive had the idea for somehow taking a vz58 style lower with an ar style upper with a piston driven system. Would be the ultimate gun advancement imho.

Yeah, but the trigger is sub par in the VZ comparatively.

 

[Hartman23Foscari]

Yeah, but the trigger is sub par in the VZ comparatively.

I found the trigger to be quite usable and it is a trigger from 1958.... im pretty sure with modern tech we could make it better.

 

[Sean K.]

I found the trigger to be quite usable and it is a trigger from 1958.... im pretty sure with modern tech we could make it better.

Meh, I have serious doubts it would ever equal a modded AK trigger...or a decent AR one for that matter.