Hello Everyone.

I have a Colt Sporter 20" (R-6551) I bought new in 1991. It has the Colt Sear Block in the Lower Receiver behind the Hammer.

Can anyone tell me whether the Ciener or M261 22LR Conversion Kits will work with this Lower?

Thanks

Ciener will work. First host for my Ciener was a Colt Match H-bar, R6601. It has the block and there were no problems. I do not know anything about the M261 kit. The conversion is definitly worth buying, even if you have to wait for it.

Doughtful the M261 will work with the Colt Sear Block. The upper will not close all the way. It will be a couple of thousands off, don't try to force it. The bottom of the M261 is shaped like a M16 bolt carrier. To get the M261 to work with my Colt, I had to remove the top part of the block that stick up above the receiver walls. I used a dremel cut off wheel and went slowly, very slowly. On the Ciener kit the bottom is open, so the block doesn't come into play. Hope this helps.

Two4spooky - REAinPA

Thanks for both of your responses.

Looks like I’m going with Ciener.

I think I’ll also look into one of the BDM Full Size Mags.

Thanks for your help.