Cutting/threading for choke tubes?

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I recently did a deal with a fellow CGN'r for an old Stevens bolt action shotgun. I plan on using it exclusively for shooting slugs. I dunno what choke it's got, if any, but regardless I'd like to install a rifled choke. Is it possible to backbore the barrel and cut threads for a remington rifled choke? Alternately, could a gunsmith cut rifling for me in the last 6 inches of the barrel (I highly doubt this, but I thought I'd better ask)? What's the best way to go about doing this?
 
I've read a bit about cutting rifling, and the average wall thickness of shotgun barrels, and I don't think j-hooking some rifling in the last 6" or 8" of the barrel is feasible. How much thickness is required to cut & thread for a rifled choke? Anyone?

Edit; also, if anyone knows of a gunsmith in the tri-city area who's done stuff like this before, let me know :D
 
Cool :D I don't have the thing in my hands yet, so I dunno what the wall thickness is, but where's the best place to measure it? Can I just assume a nominal 0.729" ID, measure the OD and subtract? Or do I need telescoping gauges, or a dial bore gauge or something? And how long is the choke area, usually? If I measure to far forward in the bore (ie; towards the muzzle end), I'm afraid the choke (if it has one, like I said it's not in my hands yet so I dunno) will throw my measurement off. Maybe I should just wait until it gets here and take it straight to a gunsmith...
 
Unless you plan on buying the tooling to install choke tubes, the reamer and the tap. You would be better to take it to a gunsmith with the tools. To order the tooling from Brownells I think it is around $350 US for the tap and reamer.
Dave
 
to do chokes whether they are Remington or Winchester you need an OD of .840, less than that (min .820) and you have to cut and thread for Thin Wall tubes. If you are going to use it strictly for slugs you could cut the barrel back and then thread it for tubes. Remington makes a rifled choke tube that extends about 1" (?) past the end. This would give the slug a bit of a twist to stabilize it.
 
Queen Bee said:
to do chokes whether they are Remington or Winchester you need an OD of .840, less than that (min .820) and you have to cut and thread for Thin Wall tubes. If you are going to use it strictly for slugs you could cut the barrel back and then thread it for tubes. Remington makes a rifled choke tube that extends about 1" (?) past the end. This would give the slug a bit of a twist to stabilize it.
This is exactly the information I was looking for, thanx a ton :D I am definetely planning on using it for nothin' but SLUUUUGS, so a rifled choke tube would be perfect. Would you happen to know if it's possible to cut rifling in the last 6 or 8 inches of the barrel instead of boring & threading for installing a choke (I mean, is it possible for a gunsmith to do it)?
 
Anything is possible, but rifling the muzzle end of the original barrel is likely a non-starter. Right off the bat, the groove depth would be greater than the bore diameter for the rest of the barrel (unless the barrel were reamed oversize), so the slug wouldn't get spun. Most bolt action shotguns have fairly meaty barrels, so there should be lots of steel for the counterboring and threading. You might want to shorten the barrel at the same time; this would leave the walls even thicker. The original muzzle will likely have been choked by swaging it into a cone, so cutting off a bit wouldn't be a bad idea anyway. All sorts of choke tubes are available in the various proprietary thread patterns. Brownells sells a sleeve which is soldered to the muzzle which accepts screwin choke tubes. Easy installation, cheaper than reaming and threading, I've done a couple, but the parts would now be covered by Commerce Dept. export controls. ER Shaw, in the US, of course, sells rifled 12ga barrel blanks for making up slug guns. Rebarrelling a bolt action shotgun isn't much different than rebarrelling a rifle. You could install a sidemount for a low powered scope, or a scout scope, or any pattern of rifle sights. Your basic idea of making up a dedicated bolt action slug gun is a good one.
 
tiriaq said:
Anything is possible, but rifling the muzzle end of the original barrel is likely a non-starter. Right off the bat, the groove depth would be greater than the bore diameter for the rest of the barrel (unless the barrel were reamed oversize), so the slug wouldn't get spun.
I didn't consider this until recently, I can't remember the logic I used to convince myself this was a good idea, maybe I was thinking of rifling the existing choke and hoping that it would be able to grab & spin the slug? If it's a cyl. or improved cyl. choke, that won't really happen though, and if I cut the barrel back to get rid of the choke then the rifling definetely won't be grabbing anything :p

Hypothetically though, if one were to rifle a smoothbore barrel as I described, would there be any spin imparted by gas blowing by the slug through the rifling grooves? It sounds horribly inefficient when I describe it, and I doubt there would be any benefits so you're right, it's a non-starter :D

Thanx for the info, I'll probably end up taking the damn thing to a gunsmith though, sounds like it's gonna be a bit of a wrestling match for me, especially not having the right tools :rolleyes: Anyone have a rough idea how much it'd cost for a gunsmith to ream & tap for choke tubes?
 
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