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Discussion Starter · #1 ·
Got some new help in the shop that has allowed me to get caught up and start devoting time to new projects. So my Christmas break project was tweeking the MP-5 trigger. I tweeked a lot.

I had a good prototype 18 months ago, but it went on the shelf, plus I realized that in a .308 with a longer bolt stroke, it needed some additional twists. So I have a new trigger put together. Took about 3 or 4 iterations to work out all the details, but it feels fantastic in the lower. Today I'll get it in both a 9mm and a 308 to make sure it cycles and pops a primer, so I know I have the geometry right.

Goal is to have a good pre-production trigger running at SHOT show in 2 weeks. It's looking good.

Trigger will be a two-stage. Pull will be about 4 lb. Reset will be short. Takeup will be smooth, due to NiB coating. All parts will be CNC machined from billet tool steel - nothing is cast. This will be an entire drop-in trigger group - no parts interchangeability with OEM parts. It will be ambi, so it will convert every lower to an ambi lower, though I'm still designing the selector. I can make an ugly selector that will be compatible with both metal and polymer lowers, or I can make nicer looking ones, but the two lowers will need different levers, or a different safety cam. Gotta figure out which way I want to go on that one.

Updates coming, as events warrant.
 

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Discussion Starter · #3 ·
I'll get some.

Trigger pack was tested in both a 9mm and a 308, and it popped the primer, and cycled smoothly, so I got the geometry right. Next step is scaling up the one I made to make a half dozen, possibly using heat treated steel, likely a housing in aluminum.
 

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Sounds like an awesome project, keep us posted!

As far as the selector goes, HK people like things to look original/factory. Regardless of whether its ambi or SEF, I would say the more you can make the selector look factory German, the better. Some folks straight wont buy it if it looks weird.
 

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The factory extended selectors are great, as long as you can pick whether you want it on one or both sides.

A lot of folks weren’t happy with an unnamed trigger company, whose selectors both looked weird and also would interfere with your trigger finger side.

Glad to see progress.
/signed/
A SAR95 SS trigger pack owner.
 

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Any updates yet? I’ve got some of your M14 triggers & love them. I have a SP5 I’m wanting to try out a trigger for.
 

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Subscribed for interest! Art I talked to you at Shot. Guys...anything he makes will be an excellent product. The man is a genius.

Oh and...Thanks again for the Scar carbon scraper bit!
 

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Discussion Starter · #8 ·
Couple of weeks of down time in March and April. My two machinists stayed home, and I found myself spending my days on facebook and reading up on covid stats. Kind of depressing, actually.

But we have rounded the bend, and I've gotten back to the grindstone. Plus, a couple of my suppliers were working while I was not. So I have trigger hubs and hammer hubs, I have springs, I have steel ready to go for all the parts, my aluminum extrusion die was completed and a first run was made for the trigger housings, and I spent time on the CNC, programming the final machining of the housing. This weekend I'll build in the prototype parts to confirm all my dimensions, and I think Monday I turn the EDM machine loose. I also need to get a small batch of housings anodized, just to confirm all my hole sizes. Hard coat anodizing adds about 0.001 to 0.0015 to a surface, so hole diameters shrink by 0.002 to 0.003. I'm using a 4mm drill for the pivot holes (0.1575) for pins that are 0.154, so after anodize, it *ought* to be perfect, though I'd like to check first before I make a bunch of them :).

So - good progress, despite everything else.
 

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Nice. I have your Tavor RPS trigger with the aluminum housing which I got in 13 or 14 (got the Tavor in 13 when MD lost its mind and did a quasi AWB) and it is a fine piece of work. Will keep an eye out
 

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Very nice! I know you guys put in a lot of hard work to get this completed. Look forward to getting my hands on one soon. 👍
 

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Done. Test fired the first production model today, both in an MP-5 in 9mm, and a PTR-91, chambered in .308. Worked great!
Awesome!
Can’t wait to try one out!
 

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Discussion Starter · #17 ·
Semi-only. Will not accept a sear. This was a ground-up design, so it is not compatible with any F/A parts.
 
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