Rifling.

[sharpshooter]

I started doing some experimenting last night with rifling a short section of .200 ID steel tubing and actually got some interesting results. Rough but interesting. I modified a .218 drill bit and basically pushed it through the section of barrel and got a recognizable spiral.  The steel tubing section I used does not have a thick enough wall to cut much more than a visible spiral but does give me reason to think that with a bit more time and experimentation with cutter angles and materials I can get an effective rifling. I did not have any barrel material on hand with either a larger bore nor thicker wall to play with but am looking for something to fill the bill.
If and when I get some substantial results I will post pics and descriptions. Wish me luck. 

[Pellethuntr]

I have heard of guys doing a similar process with PVC pipe.. Obviously PVC is easier to cut, but you still have the problem of getting a consistent twist rate.. Have you put any thought into that aspect of it yet? I am interested to see what you come up with 

[sharpshooter]

The twist rate should be able to be controlled by the degree of angle of the cutter flutes. I`m going to try it with something similar to the tip of the drill bit with two cutting flutes and changing the angle. I will probably start with a 1/2 degree angle of cut on the flutes and go from there. As I said the rifling was rough but significant and when I forced a .22 pellet swaged to just a hair over bore size it does twist as it goes through the section of barrel I used. It was about a 4" piece. You could see the rifling marks left in the pellet after forcing it through. This is all still very preliminary.
We have a family member that is in tool and die and I am going to see if he might be interested in making up a couple of trial rifling bits. I may also try for a button rifling bit that would be pulled through the bore. Which ever way works out I`ll go for a 6 groove bore. I`m going to do a bit more research into twist rates and find what angle for the flutes will give the twist rate needed. I`ll keep everyone interested up to date with any results.

[Pellethuntr]

The twist rate should be able to be controlled by the degree of angle of the cutter flutes. I`m going to try it with something similar to the tip of the drill bit with two cutting flutes and changing the angle. I will probably start with a 1/2 degree angle of cut on the flutes and go from there. As I said the rifling was rough but significant and when I forced a .22 pellet swaged to just a hair over bore size it does twist as it goes through the section of barrel I used. It was about a 4" piece. You could see the rifling marks left in the pellet after forcing it through. This is all still very preliminary.
We have a family member that is in tool and die and I am going to see if he might be interested in making up a couple of trial rifling bits. I may also try for a button rifling bit that would be pulled through the bore. Which ever way works out I`ll go for a 6 groove bore. I`m going to do a bit more research into twist rates and find what angle for the flutes will give the twist rate needed. I`ll keep everyone interested up to date with any results.

Sounds like a good plan.. I am interested to see what your results are, keep us posted