Anybody re-cut a choke bore.............

D

Don

New member
..............my active hunting days may be over and I am in the process of letting go of some of my hunting equipment, specifically to my younger brother, and I have an old side-by-side double barrel Remington 12 gauge that I would like to give to him.

Problem is, I guess it was originally built as a goose gun with both barrels as full choke, which has bothered me since I have always felt the biggest advantage of a double gun was to have 2 different choked barrels to choose from depending upon the distance range of the game.

So I would like to re-cut the full choke of one of the barrells to a modified choke to make this gun more versital and usable.

How difficult is it to re-choke a 12 gauge barrel? I have the necessary size expanding reamers and spring tension expanding stone hones, although I am not sure they are specialty built for bore choke cutting.

How far down from the muzzle is the choke cut made?

Anybody done this with satifactory results, tips?................Don
 
Don, in the trap shooting game I used to play, barrels and forcing cones were recut all the time on guns newly acquired.

If you really want a good result and the shotgun barrel you are working on has a short cone, I recommend getting a forcing cone reamer ground first and recut the forcing cone first if it is short. This tapered forcing cone causes less shot to be damaged and gives a more even pattern.

After elongating the forcing cone then repattern the barrel with the load you intend to use. The elongated cone will cause a slight net increase of choke.

Recutting chokes is a trial and error process. Oh sure there are "reduction amounts", say 0.008" for IC, etc but the really best way is to ream, pattern, then remeasure till you get the % choke you want. Ream carefully because you can't put it back.

Using the standard straight flute adjustable reamers, I perform the operation by hand using a 12" long tap handle to turn the reamer.
 
JerrySharrett said:
Don, in the trap shooting game I used to play, barrels and forcing cones were recut all the time on guns newly acquired.

If you really want a good result and the shotgun barrel you are working on has a short cone, I recommend getting a forcing cone reamer ground first and recut the forcing cone first if it is short. This tapered forcing cone causes less shot to be damaged and gives a more even pattern.

After elongating the forcing cone then repattern the barrel with the load you intend to use. The elongated cone will cause a slight net increase of choke.

Recutting chokes is a trial and error process. Oh sure there are "reduction amounts", say 0.008" for IC, etc but the really best way is to ream, pattern, then remeasure till you get the % choke you want. Ream carefully because you can't put it back.

Using the standard straight flute adjustable reamers, I perform the operation by hand using a 12" long tap handle to turn the reamer.
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Uh oh, now you have me scared Jerry. I was hoping for a simple ream, hone, and shoot operation.

Sounds like I need to study up on forcing cone reamers and their use.

Maybe I need to turn this over to a local shotgun gunsmith with all the right equipment, reamers, and experience.............problem is they are as hard to find around here as a qualified BR smith, and this shotgun probably does not justify the expense.................Don
 
My 2 cents worth...

PT&G, Manson Precision, JGS, and Clymer all sell the proper tooling.

For the time and expense of buying your tooling and making your jigs for this job it is less expensive and you will be happier to just send it to Briley in Houston.

Nat Lambeth
 
Don said:
Uh oh, now you have me scared Jerry. I was hoping for a simple ream, hone, and shoot operation.

Sounds like I need to study up on forcing cone reamers and their use.

Maybe I need to turn this over to a local shotgun gunsmith with all the right equipment, reamers, and experience.............problem is they are as hard to find around here as a qualified BR smith, and this shotgun probably does not justify the expense.................Don
Click to expand...
Don, shotgun barrel work is an art, a science, and some black hokus-pokus!!

It is not really that bad but I just didn't want to see you mess up a good shotgun. Changing barrels on a shotgun, as you know, is not as simple as a rifle.

If you feel uneasy, do like Nat suggests and sent it to Briley or Gary Yankee.
 
The choke likely extends only a couple of inches down the bore at most and then starts a taper to bore diameter. Look down the muzzle end to see. (use what I hope are the obvious safety procedures)

Ideally you would have a bore micrometer that lets you measure the bore and choke diameters to determine constriction. Even if you don't have a real internal bore measuring tool you can get useful measurements at the muzzle with dial calipers. Just record the number it gives you then cut and measure until the measurement reads larger by the amount you want. Cutting out .010" will get you a fairly different choke effect, something like modified choke.

So shoot it on paper to see what its doing now before you cut, then cut about .010" out and shoot it again. If you then have the desired pattern you are done, if not loose enough, cut out a bit more.
 
SHOTGUN BARREL ALTERATIONS FOR STEEL SHOT

Forcing Cone Alteration:

Factory shotgun barrels usually have a fairly short and abrupt forcing cone. The forcing cone is the tapered area just ahead of the chamber where the shell is contained. Altering the forcing cone, so it is one and one half or two inches in length, reduces recoil and improves the pattern density. Trap shooters and skeet shooters have been doing this for many years. It is a good benefit to the steel shot user as well.

Choke Alteration:
Choke designation from the tightest to the most open are:
Extra Full, Full, Improved Modified, Modified, Skeet II, Improved Cylinder, Skeet I, and Cylinder Bore.

Steel shot does not require the constriction that lead shot needs, to produce good patterns. In fact too much constriction, causes poor, erratic patterns, and in some cases, permanently damages the barrel. I have seen barrels bulged at the choke, I have seen barrels where the choke split right open, from using steel shot.

For steel shot, with thin barrels, chokes should be altered to at least Skeet II. Often, over & under, and side-by-side shotguns, are best altered to Skeet I and Skeet II chokes. Heavier barrels can be left at Modified choke but may see an improvement in the pattern if opened slightly.
 
henrya said:
The choke likely extends only a couple of inches down the bore at most and then starts a taper to bore diameter. Look down the muzzle end to see. (use what I hope are the obvious safety procedures)

Ideally you would have a bore micrometer that lets you measure the bore and choke diameters to determine constriction. Even if you don't have a real internal bore measuring tool you can get useful measurements at the muzzle with dial calipers. Just record the number it gives you then cut and measure until the measurement reads larger by the amount you want. Cutting out .010" will get you a fairly different choke effect, something like modified choke.

So shoot it on paper to see what its doing now before you cut, then cut about .010" out and shoot it again. If you then have the desired pattern you are done, if not loose enough, cut out a bit more.
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After the first 0.010" you better go carefully. Many full choke barrels only have about 0.025" of choke. I've never found a relationship between thousants of an inch and amount of choke. Shootng on paper at a yardage is the bottim line. 40 yards for a trap gun, etc.
 
The relationship of thousands and an inch to actual choke does exist to an extent but it is not always a fixed figure for any choke designation...

Choke is largely based on the amount of constriction so the bore needs to be measured well before the choke... many shotguns do not have the exact bore diameter they should have...some are way too tight, others are loose... the length of the choke will have some bearing on the pattern as well...

Steel shot patterns quite differently than lead and often different brands of shells pattern differently as well.
 
Send it to Briley and have them install screw-in chokes. If you have the money, have them lengthen the forcing cones too.
 
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SGJennings said:
Is the Remington SxS safe to shoot with modern ammo?
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Greg, if you are talking about the Remington M1894 or M1900 sxs there were three versions. A Damascus barrel version, a Damascus pattern barrel version, and a proof steel version. I have a Damascus pattern version M1894 and shoot it occasionally. Both it and the proof steel barreled are safe to shoot. You can shoot the Damascus barreled gun with black powder loads if the barrels are not pitted. http://www.wisnersinc.com/additional_info/RemingtonDblID.htm
 
henrya said:
The choke likely extends only a couple of inches down the bore at most and then starts a taper to bore diameter. Look down the muzzle end to see. (use what I hope are the obvious safety procedures)

Ideally you would have a bore micrometer that lets you measure the bore and choke diameters to determine constriction. Even if you don't have a real internal bore measuring tool you can get useful measurements at the muzzle with dial calipers. Just record the number it gives you then cut and measure until the measurement reads larger by the amount you want. Cutting out .010" will get you a fairly different choke effect, something like modified choke.

So shoot it on paper to see what its doing now before you cut, then cut about .010" out and shoot it again. If you then have the desired pattern you are done, if not loose enough, cut out a bit more.
Click to expand...

Hi Henrya,

Your approach is what I originally envisioned for re-cutting one of these barrels.............I was not aware of the forcing cone issue which complicates things and might make it more trouble than its worth for this old double.

I dont have a dedicated shotgun bore i.d. measuring tool, but I was going to slug the bore with a pure lead plug, the same way we do with our centerfire rifles to get the various dimensions, at least within the general ballpark, and go from there......................Don
 
SGJennings said:
Is the Remington SxS safe to shoot with modern ammo?
Click to expand...

I believe so. I have shot both 2 3/4" and 3" shotshells in this gun. I believe it dates to a 1940's era double, double trigger, internal hammers, definately not a damascas barrel.

I will have to pull it out of the attic storage area and take a photo of it, check for date stamps, and post the picture on this thread.

The exterior is all aged and weathered but the barrel bores are mirror finished...............something that I would never be able to duplicate by just reaming. A hone or polishing operation would definitely be required to match the exisiting bore finish.................Don
 
Don,
This won't answer your question, but if I were you I'd leave it as it is. Those old doubles with both barrels choked full are getting rarer by the minute. It's value is better if it remains as it was made.
That said, you can use an expandable reamer to ream out some of the choke if you so desire. As someone said, take out a littel and shoot it and see how it patterns. It's not rocket science.
I have to laugh when I hear all the forcing cone lengthening stuff. Before I got into rimfire BR shooting I was into outlaw shotgun shooting, match guns shot for rmoney. Full custom barrels, bull barrels, 36X scopes, etc. BR shotguns, if you will. My guns had NO forcing cone at all! Just a 90 Degee transition where the unfolded shell ended and the bore began. They would shoot 1-1/8th oz. of #9 shot in a hole bout the size of a nickel at 20 yards! Step chokes, with two step downs in the ckoke and then a parrallel as long as the shot column at the muzzle.
 
Hey Big Guy

Just to further confuse the issue, I have all the tooling to put in removable chokes if you would like to use it. Pumpkin
 
If all you want to do is open up a choke take it to someone with a Sunnen Hone and have it honed out. .010" with a hone is no problem and the hone will self center in the bore. Another nice thing about the hone is you can sneak up on the size with no worry of chatter or going oversize.

Dave
 
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