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.
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.
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.