Cap Head, Hex Drive, Pistol Grip Screw with Washer
Shown as parts 82 and 83 Above.
I'm not sure when it became OK to cheap out on AR Lower Parts Kits and put in screws with big straight slots and forget the lock washers... but it happened and that annoys me. So I bought the proper grip screws and washers in bulk and put them in all my rifles.
Offering up my extras here as add on items. Throw out those cheap screws that came with that bargain kit and get it 'right'. Its even easier to assemble when you use the proper screw with washer to hold your pistol grip to your rifle. A drop of blue thread locker should be used to help hold them into the lower.
I'm not sure when it became OK to cheap out on AR Lower Parts Kits and put in screws with big straight slots and forget the lock washers... but it happened and that annoys me. So I bought the proper grip screws and washers in bulk and put them in all my rifles.
Offering up my extras here as add on items. Throw out those cheap screws that came with that bargain kit and get it 'right'. Its even easier to assemble when you use the proper screw with washer to hold your pistol grip to your rifle. A drop of blue thread locker should be used to help hold them into the lower.
These can be used in other applications such as automotive use.