Finding top center of a shotgun barrel

[JeremyK]

So does anyone have any advice for finding top dead center on a shotgun barrel so I can drill and tap for a front sight bead? Basically, I've got two shotguns that I shortened the barrels on, and I want to install beads, but can't puzzle out how to mark/punch/drill/tap a hole so that it's (more or less) perfectly centered and not cantered one way or the other. Brownells USED to sell a top dead center punch, but it's been discontinued and can't find one anywhere

Tips/advice would be appreciated.

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[Alexx1401]

So does anyone have any advice for finding top dead center on a shotgun barrel so I can drill and tap for a front sight bead? Basically, I've got two shotguns that I shortened the barrels on, and I want to install beads, but can't puzzle out how to mark/punch/drill/tap a hole so that it's (more or less) perfectly centered and not cantered one way or the other. Brownells USED to sell a top dead center punch, but it's been discontinued and can't find one anywhere

Tips/advice would be appreciated.

Do you have a drill press? If so that with a vice mounted to it and pair of calipers will get you close enough you would never tell. You put gun in vice, level it, mark center. If you do not have this Harbor Freight would have some that will work for what you want and not cost much at all. Then you have them for the next "need". For just putting a bead on like that you don't need much to get so close you would never be able to tell.

 

[MountainBear]

Let someone with a mill, a vice, a machinists level, and an edge finder locate then drill and tap it. Unless you have the right tools, there is plenty of room for error.
If you've chopped a barrel back close to minimum length, often you get one chance.
Let @Velzey do it is my advice. I know that isn't the answer you wanted, and I apologize, but it's honest...

 

[Stomper]

Shade tree gunsmithing idea.... Assuming the receiver has a flat top running down the middle, equally bisect it lengthwise in 2-3 places then take a 2' (or 3') straight-edge and align it down the barrel using those 2-3 benchmarks on the receiver to keep the sight-line perfectly parallel with the barrel, which should put you TDC....

 

[NWCustomFirearms]

With a milling machine and an edge finder

 

[JeremyK]

With a milling machine and an edge finder

If I had a mill, to go with my edge finder, I wouldn't be posting this

 

[Alexx1401]

If I had a mill, to go with my edge finder, I wouldn't be posting this

It's really not hard to do this at all. Some are poking fun at it but it's really not rocket science. Trying to put a set of sights on one, now that is a little more involved. Just putting on a new bead is not hard. As long as you have drilled and tapped something before?

 

[JeremyK]

It's really not hard to do this at all. Some are poking fun at it but it's really not rocket science. Trying to put a set of sights on one, now that is a little more involved. Just putting on a new bead is not hard. As long as you have drilled and tapped something before?

Oh yeah, I drill and tap all day long, I just need it to be done right the first time; I've got the beads arriving in the mail sometime this week from Numrich

 

[Alexx1401]

Oh yeah, I drill and tap all day long, I just need it to be done right the first time; I've got the beads arriving in the mail sometime this week from Numrich

Then it would be pretty simple with basic tools.As mentioned trying to put a set of sights on one is a little harder but just a new bead is not hard to do well enough that you will have no problem with it.

 

[peternov01]

if you have a vice, level the gun in it, once it is solid you can us a tool like:

to find center and punch it for drilling reference. the fancy ones with the level and degree finders are 60-100 bucks new but can be found used for a lot less. Anyway this is what i would use, you can google some videos and see them in use. the first one is a Flange wizard and the third one is a curv-o-mark, here is a link to a quick video.

 

[Goosebrown]

Turn the shotgun upside down. Place it in a vice you know is level with the barrel at a slight downward angle. In the muzzle drop a little oil on the side of the inside of the barrel. Where the drop ends up is the absolute top (bottom) of the barrel

 

[DirectDrive]

With the receiver/barrel dead nuts level and with good measuring tools/skills you could do this...

 

[edzz]

Without knowing what equipment / tooling you do have access to, and not knowing what type / brand of shotgun (s) you have all we can do really is spitball.

My wifes suggestion is not likely to meet your needs.
https://www.amazon.com/Applicator-B...t=&hvlocphy=1014226&hvtargid=pla-799011263887

 

[JeremyK]

Without knowing what equipment / tooling you do have access to, and not knowing what type / brand of shotgun (s) you have all we can do really is spitball.

My wifes suggestion is not likely to meet your needs.
https://www.amazon.com/Applicator-B...t=&hvlocphy=1014226&hvtargid=pla-799011263887

One Stevens 820B and one Stevens 67E. I've got several vices, a drill press, various levels, punches. Basically I've got everything I need (I think) to do it, just not the know-how to do it right and not have everything on there wonky. I'm liking the looks of those v-block pipe-gauges with the level and the punch.

Also, my girlfriend recommended that I vajazzle the thing as well