Home Forums Reloading 16 Gauge Society Gonna threading a 16 ga barrel for screw-in choke

Alright, I don't mean to be disrespectful and necro an older post, but after not being able to get a tap and thread the inside of the barrel, I chose to simply make a choke sleeve instead. Which will serve the same purpose as a screw in choke but I'm going to make it permanent and more like a fixed choke.

I'm not comfortable brazing the new choke in place because it's essentially an extra full choke and I prefer to weld it and then clean it up afterwards. So, I'm going to have a buddy mig weld it and I'll clean it up with some files and sandpaper afterwards. He said I could swing by Thursday morning probably.

Here's the progress so far.

I bought an 18mm reamer and made my own pilot bushing and extension to bore out the barrel to ~.710"



I reamed it deeper than the photo shows. But I took the pic before completing that step because I wasn't sure whether the camera would show the inside of the barrel very well had I waited too long to snap the pic



I turned the choke on the lathe. It started out as .75" OD and closer to .619" inside diameter, which is a little tighter restriction than a full choke (.624")



I used the taper reamer to make the mouth of the choke slightly wider than the barrel bore so it wouldn't snag the wad as it enters the choke. This pic is from the inside view using a bore camera. The choke had a lot of tool marks in the pic because I wasn't done with it yet. But, before I finished it, I wrapped a shotgun bore brush with some 400 grit paper and chucked it back up in my lathe and left it in there at 300 rpm for about 5 minutes. It's mirror smooth now, but this pic is showing the progress tool marks and all.



The choke will be a little less than 2 inches long altogether and will protrude out of the front of the barrel about a half an inch to give plenty of room for the weld. The choke tapers from about .669" down to .619" with the last 3/8-7/16" of an inch entirely being .619 constriction and is .065" wall thickness which is a little thicker than the barrel wall was to begin with. I'm hoping the long taper will help compress the shot well while not causing it to start kicking like a mule. The taper transition is very near 1-7/16" long. And as I mentioned, after polishing it, is now mirror smooth.

I plan to use a long string and fender washer down the bore to hold the choke tube tight against the barrel/shoulder until my friend spot welds it to ensure that it's flush up against the inside of the barrel and everything is tight. After he's done welding, 'll clean up the slag and blue it and put a ramped front bead on it and it should be done.

Again, I kinda hate to necro the topic, but since I couldn't thread it for screw in chokes, I figured making a choke sleeve will essentially be the same end result.