Has anyone had difficulty finding a lower that can be fitted to an IUR?
So far I have tried two stripped lowers. One an Aero lower and the other a Blue Line lower. Both of these lowers fit other uppers but will not mate with the IUR. It appears that the hole in the IUR rear takedown pin lug is a few thousandths higher than the matching holes in the lowers. The result is that the rear takedown pin can't be inserted.
Kinda reluctant to buy a 3rd lower. Could the IUR be out-of-spec?
So far I have tried two stripped lowers. One an Aero lower and the other a Blue Line lower. Both of these lowers fit other uppers but will not mate with the IUR. It appears that the hole in the IUR rear takedown pin lug is a few thousandths higher than the matching holes in the lowers. The result is that the rear takedown pin can't be inserted.
Kinda reluctant to buy a 3rd lower. Could the IUR be out-of-spec?
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