hey i have a spikes lower and i noticed the spring hole for the takedown pin is threaded. anyone know that size or have a little hex head screw for that?
not exactly what you wanted, but it should of come with the screw...and you can run without it, I do and have no problems..pointless when the grip retains the safety spring.
Could of been Seekins that didn't throw it in there, thats who makes them. I recieved my IRMT-R upper last week and it was missing the titanium barrel nut. A quick call to seekins should get you fixed up. Still waiting on my barrel nut but I only called them wed of last week.
Insert detent, insert spring, screw in the receiver extension (that has castle nut and receiver plate already installed) until buffer retainer is held in position. Piece of cake.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WildBill3/75</div><div class="ubbcode-body">The seekins lower captures diffrently, it's located on the bottom where the pistol grip attaches like the safety spring. </div></div>
4-40 is correct. FYI Spikes and Aero Precision are two brands of lower that come threaded for the "takedown detent spring mod" from the factory. There may be others but those are two I have personal experience with.
If you're gonna do the mod make sure you cut down the detent spring by the length of the set screw (1/8") or the takedown pin will bind.