I have a Springfield M1 Garand chambered in 7.62x51. While using the the adjustable gas plug i used all the settings and even with the smallest setting i experienced failures to feed. I would hand cycle the action and i might be able to get 2 rounds off before i would experience a failure to feed. I want to know is this just a case of still too much gas escaping and all i need to do is use one of the blank adjustments provided and drill a smaller gas opening, or could it be a weak return spring ? I know the bolt can strip a round and feed into the chamber because i placed the USGI gas plug on and the weapon functioned properly mostly. Also when loading a full 8 round enbloc clip the first round usually always needs the op rod handle tapped to help feed and close the bolt, but this i think is normal and not a result of a weak return spring. Now whether i use the adjustable gas plug or USGI one i always experience a second round failure to feed causing me to hand cycle and continue firing. I noticed if i remove one round and load only 7 rounds i never have a second round failing to feed. Is this caused by maybe the 7.62x51 rounds being fatter at the base making the fit in the enbloc clip (which was originally designed for 3006 casings) too tight and causing the second round failure to feed, or again is this caused by a weak return spring not putting enough upward pressure on the bullet guide forcing the round to catch the bolt face to feed? Thank you.