A long time ago I built a 22lr conversion unit for my 9mm AR carbine. I know that Oly Arms did one but it was later on down the road and they used the M261 conversion unit and I used the Ciener. I honestly didn't know if there would be any value in having a conversion like this for 9mm carbines but it does seem difficult to find 9mm ammo these days. The idea with the 9mm/22lr conversion was that you could take out the 9mm bolt and slide in the conversion with it's own 22 caliber barrel and shoot less expensive 22lr bulk ammo. Obviously nobody gave a darn 15 or so years ago but I thought it might fly these days. The same thing could also be done for all those 7.62X25 carbines although the diameter of the conversion barrel would need to be turned down. What brought this to mind was the fact that I have a 9mm carbine that I'm having trouble finding ammo for that doesn't cost an arm and a leg. I know that 22lr ammo is in short supply but not as much as 9mm or 7.62X25. Just a thought.
Edit to add: the Ciener unit was designed to also run in full auto AR's and there are several companies out there that are building ciener unit copies.
Last Edit: Mar 15, 2013 11:16:38 GMT -5 by 22boomer
Tim, I got the unit together and it works great. It's an old Ciener unit on which I modified the chamber adapter and added a barrel that fits inside the 9mm barrel. The barrel that fits into the 9mm barrel has brass bushings to make for a tight fit but not so tight that the barrel can't be installed and removed easily. I use a Black Dog magazine right now but I do still have the original metal Ciener mags in both 10 round and high capacity. I can't wait to see how the accuracy is compared to the original 9mm round. The last one I built put the 22lr rounds just about in the same POI as the 9mm at 50 yards.
I have 9mm ammo but you know haw easy it is to go through a bunch of mags worth of that stuff. 9mm and 22lr are both kinda hard to find right now but I do have better luck with the 22lr than stuff like Winchester white box 9mm ammo. I've saved up all kinds of 22lr ammo and thought it would be nice if I still had that old 9mm-to-22lr conversion unit I built years ago. I gave the darn thing away so I went ahead and built another. All that needs to be done is pull out the 9mm bolt and the magwell adapter, then install the Ciener conversion kit with the 22lr barrel and use a Black Dog mag or one of the original Ciener mags.
The only other carbine I was thinking about building a conversion for is the 7.62X25 DI carbine but I don't think I have the ability to decrease the barrel liner diameter without making it weak. HK made a 22lr conversion kit for one of their 30 caliber rifles (expensive kit) so I guess it can be done but I don't think it will be by me. This is a picture of the HK91 conversion kit for 22lr.
so it can be done. Redman barrel liners measure 0.308 in diameter so just a hair must be taken off that diameter. By the way, that HK kit costs $1000 and I've seen them costing more.
Last Edit: Mar 23, 2013 16:21:01 GMT -5 by 22boomer