I will preface this by saying this is my interpretation of the rules and that I have reached these conclusions after consulting the BATF Seattle Division. Your local BATF region may have other interpretations of the regulations, please check with them first.
Please read this whole thing before you go further than the first part of the post and get your panties in a bunch and tell me that I will go to jail forever for doing this.
There has always been a great interest in a Handi Pistol here on the boards and other places. After lots and lots of thought, research and personal consultation with the BATF Seattle Branch I am ready to show the work so far.
First, this is why it is OK to do this:
You must absolutely start with a gun that was never controlled as a firearm according to the gun control act. You must start with what is classified as an “antique” firearm, which is what a B.P. Muzzle loader is classified as. As such, it is not regulated by the gun control act and you may build any weapon that is legal for you to own in your state using its parts. You may not build it for someone else or for the purpose of sale. Once it is built it becomes a modern firearm and is subject to all the regulations that apply to them. You must also build it as a pistol first, if you build it as a rifle then it is a modern rifle and converting it to a pistol would be illegal, so start with a short barrel. This conversion is like the practice of putting a center fire conversion cylinder in a black powder M.L. revolver, which is a common.
I began with a Sidekick frame (which was never sold as a modern firearm). The Sidekick frame is narrower inside than a standard Handi Rifle is, so to enable a modified H&R C.F. barrel to fit, you must machine out the front of the frame to the proper width. After doing that, you also need to shorten the underlug of the H&R CF barrel and cut a new hinge pin notch in it, there are pictures of the process below. It also has a fireing pin the size of a modern shotgun pin, not the fat pin of the earlier BP only Huntsman frames. This is not an easy task for the home hobby shop, but with some thought and a little skill it is within reach of the more advanced hobby machinists.
Wish I could build more of these, but please don’t ask, I cannot, you must do it your self if you want one.
This project is a 22 Hornet pistol with a 12 inch barrel, I used a commercially available hand grip and a modified H&R forearm for the project. I have not cut the extractor slot and have not fired it. I have a 2-7X32 pistol scope for it when it is finished and will Parkerize the barrel after getting it drilled and tapped for the scope base. I started with a Hornet because it is a nice low pressure round and still useful for varmint hunting, I also happen to have a reamer for it.
Take a look at the pictures (some are of a Stainless Sidekick which was just too nice to cut up) and I will answer any questions on how to do it that you may have, Again, after talking to my local BATF I am satisfied this OK to do, (I would be kind of stupid to post if I weren’t). If you have questions about this part of it please talk to the BATF personally, they are really a nice bunch of people if you are not a bad guy. I have more pictures of the barrel mods etc. to follow later. Larry