Posted :: 7/5/2004 6:36:08 PM
I finally managed to get an Armalite single stage trigger for the AR-10 to fit the link into the AR-10. The results look very good but there will need to be some milling! The first problem is that the larger opening for the FCG does not come to the rear far enough to allow the Lightning Link to sit up against the disconnect, much less trip it, when the hammer is caught by the disconect. See the folloiwng photo:
Larger version:
quarterbore.com/images/qbi_ar10_ll_huge.jpg
This problem can be solved by milling the receiver to the wider diameter as shown with the pencil marks on the lower.
The second problem is that the larger rear takedown pin and subsequent larger rear takedown lug on the AR-10 does not allow enough room under the lug for the link to fit into the lower. In addition, the selector of the AR-10 is at the same height of the shelf of the AR-10 so I do not think that it will be desirable to try and mill the shelf on the AR-10 to make it fit. Instead, I think I will simply remove some material from the bottom of the rear takedown lug on the upper receiver to allow the link to fit under it.
The third issue I am expecting to have with the lower is in the rear portion of the lower as the rear takedown lug goes almost to the radus cut towards the buffer tube. I wouldn't need to mill this to the rear much to give me the slack I need or I could evaluate milling the rear portion of the takedown lug.
As for the bolt carrier, obviously I need to get the lower to function with the link before worrying about the carrier becomes important. With the LL, you can manually work the link to trip the disconnect without an upper on it and I need to be able to do the same with the AR-10 lower to make sure the mods to the carrier will be correct for the timing of the link.
This still looks like a very great project! As an aside, I managed to get a M16A2 burst kit and dremel and grind it so I have a select fire kit for the Bushmaster AR-15 and the she is golden for the 9mm, 223, and 7.62x39 uppers. By using the M16A2 hammer and cutting off and rounding the rear half of the hammer (removing the hook) it works fine even with the 9mm bolt. Thanks for those that care to share with me as I
slowely work on this!