Firs off I am sorry if this has been covered before but My first AR is waiting on this part.

I need the size of the grip screw,  I believe a 1/4 inch fine thread will do it but i need to know the length.

   Have torn the house and packing materials apart and cant find the screw or lockwashers  so either they never got sent or I really lost them.  everything else was there and is installed.

Second question   What size allen wrench is needed for that little bitty set screw on a Magpul trigger guard?

Thanks
Mike

Welcome to AR15.com!  

1. The AR grip screw size is 1/4" with 28 threads per inch and 1" long.
2. I have never used a Magpul product.  Sorry.

Thank You  Now I can get it running tomorrow.
 I missed the hardware store by about 3 minutes and Wal Mart does not have any fine thread machene screws no mater how many times you look at them  they are all still 1/4-20's.  I can live with the Magpul being not right but I need to put at least one round out of it.

Thanks Again
Mike