Threading bbl for chokes?

[cwebb]

Hello, if I cut an 870 Super Mag bbl from 28" to 20-ish are there barrel diameter or wall thickness differences at that length that would make threading a more complicated task than say threading a factory length barrel?
Thanks in advance for any replies!

[Synchronizor]

The important dimensions when threading a barrel for chokes are the inner (bore) diameter, which has to be below a maximum, and the outer diameter, which has to be above a minimum. As far as I know, all factory 3.5" 870 barrels use a straight, standard 12ga bore, so inner diameter shouldn't be a concern unless you buy a used barrel that was custom-overbored by a previous owner.

The minimum outer diameter I've seen quoted for Rem Choke installation (assuming you're going with Rem Chokes) is usually .85", sometimes .845". Any factory 870 barrel should be comfortably above this minimum at the muzzle, with an equal or greater diameter anywhere further back. My Express barrels are in the .88" - .89" range at the muzzle, and even my lighter-contour Wingmaster slug barrel is .876". In all likelihood, any SuperMag barrel will be as thick or thicker than my 3" barrels.

Short answer: there should be no problem threading a SuperMag 870 barrel for chokes no matter what you cut it down to.

[cwebb]

Many thanks for the detailed reply! I'll confirm bbl specs before I attempt but this sounds very promising. That's exciting news. I've been researching the process of both cutting and threading a barrel from a DIY standpoint and would prefer to do this rather than buy a SPS Predator bbl...if Remy will even sells the bbl alone.
Thanks again.

[Synchronizor]

Cutting a barrel is a fairly straightforward process for the average do-it-yourselfer, especially with vent-rib barrels, which don't need to have a front sight re-mounted.

However, threading a barrel for chokes requires some very specialized tools and more advanced skills. Unless you already have all the necessary equipment lying around, or there's some really nifty (and well-priced) kit I'm not aware of, you might be better off letting someone else handle that part.

[Odyknuck]

You can do it however the tooling alone will coast about 300 bucks for the reamer and tap. Unless you plan on doing 20 of them, you would be better off in the long run to buy a ready made barrel. here is a link on how to along with a link in the article to buy the tools.

http://ktgunsmith.com/choketube.htm

[Synchronizor]

Neat article and site, thanks for sharing the link.

Actually, $300 doesn't seem to be too bad of a price. Quotes I've seen for barrel threading are generally in the $75 - $100 area, plus shipping if you need to send the barrel out. For someone who has multiple shotguns/barrels that they want to tinker with extensively, a tap and reamer could pay for themselves pretty quick. I also found out that these tools can be rented to folks who just need them once in a while. Fifty bucks for a week's use is a pretty good deal even if you're just threading one barrel, though that deposit'll be there to bite you in the butt if the tools get FUBAR'd.

[Odyknuck]

Not sure I would rent them out personally as not everyone has the required skills to use them and how would you know? You would have to charge 300 dollar deposit just to cover your butt. Food for thought.

[cwebb]

Synchronizer and Odyknuck,
Thanks for your replies and Odyknuck thanks for posting the link to that great article.

I saw a Brownell's video that briefly demonstrated the steps and required tools which is what got me thinking.

The tools aren't cheap but I'd have to spend some money for a gunsmith to do this work so thought I'd roll that money into the cost of the tools so I can to do it myself.

I have to wait a few months before I can begin this project but I'll be documenting all of my work for forum members to see.

Thanks again!

[Synchronizor]

Not sure I would rent them out personally as not everyone has the required skills to use them and how would you know? You would have to charge 300 dollar deposit just to cover your butt.

The site I linked to lists a $250 deposit in addition to the $50 rental fee. Sounds like their butts are pretty well covered.

I saw a Brownell's video that briefly demonstrated the steps and required tools which is what got me thinking.

The tools aren't cheap but I'd have to spend some money for a gunsmith to do this work so thought I'd roll that money into the cost of the tools so I can to do it myself.

I have to wait a few months before I can begin this project but I'll be documenting all of my work for forum members to see.

Looking forward to seeing it!

[Odyknuck]

I guess I misunderstood. I thought you were talking about the OP buying them and renting them out. I did not even see they were renting the tools lol.