I bought the MCarbo parts to upgrade my trigger assembly, feeding ramp, etc. I watched the video beforehand several times and then followed it during the install. The video for the install is three years old and does reference the difference between the Gen 1 and Gen 2 for particular part differences, but I ran into an issue during the trigger assembly install. When it came to installing the trigger assembly, the video references a shim that was supposed to be included in the new parts and installed with the assembly. I had carefully sorted all of my new parts and left them in the bags until they were to get used so I didn't mix them up with the old parts. I could not find the shim so it was not included in the trigger assembly kit. I was at a loss, so I went through my parts bin and found one that looked just like it. It fit over the pin exactly as needed. Of course there was no way to tell how thick the shim should be, but I had no choice. I noticed that my rifle had a small lip of polymer on the side the shim was to be placed on, but I had no reference if this was supposed to take the place of the shim or it was in addition to it. The trigger assembly worked when all of the the parts were in place and I tested it with the ejecting side of the gun still off. I installed the rest and tightened the screws down. When I did so, the trigger would not return forward. I did some trouble shooting and finally figured out that once the screw in the center, right above the trigger, was tightened, it no longer returned forward. Once I removed the shim I installed, the trigger worked fine. The install would have taken about 3 hours, but since I had to open the gun up several times to figure it out and then reassemble it to test it, it took about 5 hours. I included screen shots of the video showing the shim that is referenced in the installation video.
The question is, does the Gen 2 not need the shim, or was I just not provided one that would work? The installation video was 3 yrs old, so it would have been nice to know if it was no longer needed/provided or if I just didn't get it in my kit. I shot the gun and everything works great. It has a nice soft trigger pull with a smooth trigger reset.
So MCarbo, does the shim still need to be installed in Gen 2's, or is it no longer needed or included in the kit?
In addition to the trigger upgrade kit, I installed upgraded screws and pins, and the same on the fore end. I also installed the recoilless charging handle (which dealing with installing the new spring end was a bitch), the bolt tube cover, the rapid deployment latch, the QD single point sling mount and sling, the recoil buffer, and a recoil pad.
All in all, I like the new parts a lot and the gun shoots great. I will be getting the upgraded rear sight as my groups were consistent, but down and right of the bullseye by about 2 inches down and 2 inches over from about 75 yards. I'm assuming this is because you have to push your face down so far to get a cheek weld that it's pushing the shots down as you do so. I'm hoping the upgraded rear sight will help with this. I have a red dot sight which I installed on a 45 degree mount using the M-Lock mounts, but didn't get my bore sight in time to try and sight it in so that still needs to be done.
Thanks.
