Hi, Garnett. Hope you like chocolate!
Usually when the term "re-choked" is used, it means reaming out the original tight choke to a more open one. This can be done with an actual choke reamer, which only a gunsmith would usually have, or by various "shade tree" methods like wrapping emery paper around a split dowel, chucking it up in a drill, then "sanding" out some of the choke.
If done carefully with a variable-speed drill, that works OK, assuming that the operator has the tools to measure the inside of the barrel accurately and KNOWS the proper dimensions of the choke degree he is seeking. Needless to say, most amateurs don't really know what they are doing; they just know they don't want a full choke!
This 20 barrel seems to have been rechoked by the "shade tree" method. However, it seems to be concentric all the way along the choke area, which indicates that the guy went slow and checked with a caliper, which is better than most such. My measurements tell me it's more like "improved cylinder" than "improved," which is OK by me. Hopefully at some point I'll have it on a gun and get to pattern it. I'd try it on my 220SC action, but it won't cock that.
The other sense of rechoking, putting a tighter choke BACK into a barrel requires adding metal. That involves either re-sleeving and then reaming the choke area (gunsmiths only please!) or adding choke tubes (" " "), which is the more modern fix. These days only really classic doubles get the re-sleeving fix, and that is usually for those that are quite valuable but have suffered a catastrophic barrel failure, or have barrels with steel that is un- trustworthy with modern ammo. Re-sleeving costs a lot, and it is hard to find a gunsmith willing--and ABLE-- to do the work.
And that's all I know about that.
Mike Armstrong
