I have an A-1 upper laying around and instead of building another 5.56, I'd like to do a pistol caliber and need to know if I can use it or not? Specifically I need to know how does the large shell deflector mount and what modifications are required to do it? Any other tips will be greatly appreciated. Jim

No modifications needed.  You will wind up with several features that don't do anything (like the forward assist and the hole for the gas tube), but that's no problem.  The gas deflector and half-sized dust cover go right on after you remove the full-sized dust cover.

Just pull the pivot rod out towards the front and the dust cover will come off (don't lose the spring).  Then put the half-sized one on the same way, followed by the gas deflector.  There's a small spring that comes in the kit which goes in a hole in the bottom of the gas deflector and bears against the receiver.  This is to keep the top of the deflector pressed tightly against the receiver.

If you want, you can also plug the gas tube hole up with some epoxy.  You don't have to, but it keep solvent from leaking out all over the place when you're cleaning.

Quoted: No modifications needed.  You will wind up with several features that don't do anything (like the forward assist and the hole for the gas tube), but that's no problem.  The gas deflector and half-sized dust cover go right on after you remove the full-sized dust cover. Just pull the pivot rod out towards the front and the dust cover will come off (don't lose the spring).  Then put the half-sized one on the same way, followed by the gas deflector.  There's a small spring that comes in the kit which goes in a hole in the bottom of the gas deflector and bears against the receiver.  This is to keep the top of the deflector pressed tightly against the receiver. If you want, you can also plug the gas tube hole up with some epoxy.  You don't have to, but it keep solvent from leaking out all over the place when you're cleaning.

+1


i would just leave the gas port hole just incase you ever decide to go back

Thanks for the replies and the help.