Ok I'm not completely sure of how to pose this question, but I will try and be as clear as possible. As it is I'm sick of waiting for DPMS to get around to making a hi-cap .22lr mag for the upper they sold me so I'm interested in going the route of the Ciener .22lr conversion which has 30 round mags available. I hear that accuaracy suffers when you put the Ciener kit into a .223 so I want to stick with having a dedicated .22lr upper. What I'm wondering is if it would be possible to use my existing DPMS .22lr upper and making whatever modifications that are necessary so that I would be able to use the Ciener kit. From what I can see the DPMS has a barrel extension where as the Ciener kit has the sub-caliber bolt/chamber adapter. If anyone is familiar with both setups and can recommend something that can be done to make the Ciener bolt compatible with the DPMS barrel or if this is even possible it would be much appreciated.

The best route to go with the Ciener is with a dedicated barrel.  Look at Accuracy Speaks, and somebody has mentioned Fulton having 22LR barrels???

The DPMS uses a COLT 22LR unit, and simply cut off the fake 223 shell at front and bored the remaining doughnut to .450 and slide the barrel into the doughnut hole so to use the real 22LR chamber.  

I have both the original COLT unit, and a pre-Ceiner (Atchisson) kit.

I'm definately set on having a dedicated upper with a .22lr barrel that's what I'm wondering if there is any way I'll be able to use my existing DPMS .22lr upper with the Ceiner conversion kit.

If hi-cap is all that important to you, perhaps you would be better served by selling your DPMS upper to someone who will use and appreciate it for what it is, and put the proceeds into a 10/22 and a pile of Butler Creek Hot Lips magazines.

Another alternative would be a Rhineland R22--AR guts, takes hicaps, superbly accurate, only costs about as much as the DPMS upper, if not less.