Barrel regulating?

[Britsmoothy]

Do any of you gentelmen know a thing or two about regulating muzzles via filing in order to bring an errant tube back on target?
My peder 12ga double has slowly been evolving into something I like, first I have had to shape the stock to get it to fit me better and now thats fine apart from finnishing etc but it does seem so that the left tube shoots to the left of which I think is common on these. I have heard of regulating the muzzles but not had it explained to me. My Greener breech loader has had quite clearly its muzzles regulated but wich way do you remove metal to encourage the pattern to shift a particular way??? Thanks, Nath.

 

[bpbrs]

you have to regulate when being built by shaping the center rib.
This pulls the barrels together to make the point of impact meet at a predetermined yardage.
Regulating also gives you pattern denstity high and low.

 

[paulvallandigham]

Filling the muzzles if often seen on original guns to regulate them. This is an old technique, probably " home grown ", because " cheap" import shotguns were common, but part of the savings was that the guns barrels were not regulated at the factory by changing the spacing of the center ribs, as mentioned above. " Best" guns were regulated at the factory, but you paid a high price for that kind of product.

 

[Todd Rickard]

I found this photo on an auction site and I wonder if anyone knows if this was an attempt to change the piont of impact?

 

[paulvallandigham]

NO, I don't think so. I think someone jammed the muzzle into something very hard, like a stainless steel pipe, and it took metal out of both barrels. It doesn't tkae much filing to move the pattern in one direction or the other.

 

[Joel/Calgary]

It looks more like those notches had something to do with the missing lug/lip that retained the ramrod. Possibly part of its function was to help hold the barrels aligned/together? Dunno.

Joel

 

[Britsmoothy]

Dear Paul, thanks for your reply and ofcourse to the others as well :hatsoff:
Do you happen to have any information on which way to file for a given direction?
I have got this gun shooting nicly now with 4 o/s cards and a 3/4 load basis and now have the stock fitting me and refinished in oil. If I can crack this last nut it would make me very happy.
Many thanks, Nath.

 

[Trapper]

I built a 16 ga fowler a year back and had the same problem. It shot 8 inchs low at 25 yards with the roundball and the shot pattern was just as low. I filed the front sight as low as possible and that brought it up a little, Bent the barrel alittle and that brought the pattern up some. Then I finally started to regulate the barrel by filing a little off the bottom (bout 12 strokes with a bastard file)and now it shoots real fine at 25 yards. You have to file about 6 strokes and test fire a pattern or roundball and see where it's hitting. If you want the pattern to go up file the bottom of the barrel, down-- file the top, right -- file the left side, I know you get the picture. I was told that filing the bottom let the gases out of the barrel first causing it to push in the upwards position taking the shot or roundball with it in that direction. An oldtimer gunsmith told me this. It seems to work for me. Just my 2 cents worth

 

[paulvallandigham]

File the opposite side of the barrel from the direction you want to move the pattern to. If its shooting to the right, then file on the right side of the tube to move it to the Left. Does that make sense to you?

What is happening is that by filing the muzzle down on one side or the other, the shot and wads are released from the barrel at different times, with the short side being released first. That allows the gases to force the short side to get ahead of the longer side of the shot and wads, moving the shot in the direction away from the short side that you filed.

This can only be done by trial and error. It is slow, hot work, as most shooters do it at the range, so that they can load the barrel and fire a test shot or two after taking a few strokes with a draw file on one side of the barrel or another. The only way you know if you are succeeding is to test the barrel ON PAPER. Or, if you belong to a club that has a metal plate for a shot patterning board, where you can just paint the metal after each shot to cover the impacts, you don't have to use paper targets.

 

[Britsmoothy]

Many many thanks for your imformation, I appreciate it.
I have to go away for a few days now but as soon as I am back I will conduct tests as to your recomendations so please wait for my reports.
Once more thankyou Paul and Trapper :hatsoff:

 

[CoyoteJoe]

Often one can regulate without modifying the barrels by adjusting the load. When a side by side is fired the recoil of the right barrel swings out to the right and the left to the left. Since some recoil movement occurs before the shot leaves the barrel this recoil swing affects shot placement. If barrels "splay out", right barrel shooting to the right and left barrel to the left it can be cured by either reducing total recoil or by increasing velocity to reduce barrel time. Before jumping into any permanent modifications I'd try reducing the shot load and or increasing the powder charge. Those load changes should bring the points of impact closer together. One sometimes must compromise, will an 80% pattern that is six inches off center bag more game or break more clays than a 60% pattern perfectly centered?
It's your gun but personally I prefer leaving the muzzles square to the bore.

 

[Britsmoothy]

Sorry for the late reply, I have been away.
C Joe, I hear what you are saying but I should be able to square the tubes of again if It does not work. They are off quite abit so I ,ll give it a try.

 

[Britsmoothy]

Well I take my hat off to you guys :hatsoff:
I filed my muzzles as instructed by Paul and others and on the first attempt it now shoots to point of aim- fantastic. I now have a stock that fits, stained and oil finished and a fine shooter if a little muzzle heavy.
The dog and I then went on a walk and shot two grey squirrel and a jack daw. The squirrel were running and the jack daw was flying fast so I am now confident, I feel shure alot of fun is to come with pidgeon, rabbit and pheasant :grin:
many many thanks for your guidence fellows :hatsoff:

 

[paulvallandigham]

Congratulations on regulating your shot pattern through filing the muzzles. Not too many men have the courage to try something like that, and I am glad you reported that it worked fine for you. After seeing a lot of double barrel shotguns from the Pre-civil war vintage on display or for sale by dealers at Friendship, I am convinced that before choking of shotgun barrels became common, this was the way the shotguns were regulated, and not just by the shooters. With the limited tools available to shotgun makers back then, regulating two barrels while they were being joined together was a major headache. This was mostly because there was really no way to control the thickness of barrels to less than .001" , so that the amount of heat a given set of barrel took on in the soldering or brazing process when the ribs were applied was just not something they could control well. A thin barrel next to a thicker barrel my warp one way or another during the joining process.

 

[Britsmoothy]

:thumbsup: :hatsoff: