Screw it, lets see if I can make an AR.22LR bolt work in my FNC

**HK51** · December 8th, 2009, 03:18 PM

So I enjoy my FNC, but the selection of parts is slim at best aftermarket support is nothing like the AR platform and the parts that are available for it are hard to come by sometimes so even if you want to buy something you might have to wait with it on backorder for a while.

As of yet there are no other uppers available other than the one that comes on the gun, and if you want to find a back up upper receiver good luck you might as well just buy a whole other gun. With the parts and aftermarket support so limited if one wants to do something they are left to their own devices

Enter the .22LR AR bolt to FNC conversion attempt

I was wandering over on FNCTalk and someone brought up the thought of trying to retrofit a .22 conversion to work in the FNC, I didn't have anything in particular to do that day and I have 2 extra Ciener .22 bolts sitting around and my FNC so I figured why not lets see what I can do with this thing.

First thing I noticed is that to even get the bolt to sit in the chamber I was going to have to cut a huge groove the entire length of the bolt to fit past the FNC ejector which sits in the path of the bolt as it slides down the receiver. After that I saw I was going to have to add a charging handle to the bolt itself to cycle it.

At first I had planned on welding everything but after a quick pow wow in my head I decided to just go quick and dirty to move the process along quickly and if it turned out I could get something to work after what I did with this bolt I could do a second prototype properly.

Step one: Getting medieval on the .22Bolt

Just from eyeballing the bolt vs ejector I knew I had to cut... a lot. And I knew that some of the places I had to cut might end up so thin that after the first round the metal splits and thats the end but to make an omelet you have to break some eggs right.

After 2 hours of cutting/grinding/testing it finally slide all the way forward

as you can see in the first picture, the groove actually cut into the chamber as I suspected it would, I believe that one could leave enough meat to not go into the chamber but trying to keep it that tight with an air powered cut off wheel just wasn't in the cards.

Thats a .22LR bolt sitting in the chamber of an FNC, as far as I know thats a first.

Now I have to add an extension to the rear of the bolt to the assembly stays all the way forward and then add a charging handle of some sort in order to cycle the bolt to see where I need to do MORE cutting so it will fit past my sear.