Author Topic: Drill & Tapping a 12 ga bbl for scope mount?  (Read 1019 times)

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Offline fredster22

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Drill & Tapping a 12 ga bbl for scope mount?
« on: November 10, 2010, 02:39:54 PM »
 Wonder what the general opinion is on drilling & tapping a 12ga 24" barrel
for scope mount for use as a donor for a 18" insert for 45 acp. Any pressure
problems or future use by another future owner for 12 ga only?  Thanks Fred
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Offline quickdtoo

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Re: Drill & Tapping a 12 ga bbl for scope mount?
« Reply #1 on: November 10, 2010, 02:48:41 PM »
It's been done, but most gunsmiths won't due to the thin chamber. Warne makes two steel scope rails that would be ideal for silver soldering.  ;)

Tim
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Offline 45LCshoooter

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Re: Drill & Tapping a 12 ga bbl for scope mount?
« Reply #2 on: November 10, 2010, 05:16:05 PM »
I worked around this issue by epoxying the insert in permamently. you may not want to do that but if you shoot a lot, you're not going to enjoy taking the insert in and out every time you shoot...well, i didn't and it was only a 10" insert.
All that's gold does not glitter. Not all those who wander are lost.
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Offline gjdykeman

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Re: Drill & Tapping a 12 ga bbl for scope mount?
« Reply #3 on: November 11, 2010, 12:20:00 PM »
I checked out the inserts, I have a 24" 12g barrel that I put muzzleloader sites on. Drilled through the chamber, used long screws and shortened them to just stick into the chamber then polished. I have fired this with over 200 rounds of all denominations. Still have all my fingers. If using the insert what's the diff. I would never sell this barrel, throw it away maybe. I haven't had any issues. To give to someone else, not. I saw a barrel blank on Numrich Gun parts. 45 long colt 26" long 1-1/2" dia. Strait tube. 77.00. Stub. machine shop and the 12g drilled barrel. long extractor. A possible project. I have a 45LC carbine on topper wood and frame. Love that gun. Don't need a 45ACP, but it would be a project.
SFC US Army 32y 8m 13d RET

Offline Spanky

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Re: Drill & Tapping a 12 ga bbl for scope mount?
« Reply #4 on: November 18, 2010, 11:20:00 AM »
I've got a 12ga. Pardner barrel with scope mount on it. I just drilled through into the chamber and tapped the holes. I measured the hole depth and ground the screws to the proper length to be perfectly flush with inside of the chamber. After that I polished up the chamber and you can't even tell where the screws are when you look into the chamber. I've fired hundreds of rounds through it without a problem.



Spanky

Offline Lazermule

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Re: Drill & Tapping a 12 ga bbl for scope mount?
« Reply #5 on: December 05, 2010, 07:51:24 AM »
I've got a 12ga. Pardner barrel with scope mount on it. I just drilled through into the chamber and tapped the holes. I measured the hole depth and ground the screws to the proper length to be perfectly flush with inside of the chamber. After that I polished up the chamber and you can't even tell where the screws are when you look into the chamber. I've fired hundreds of rounds through it without a problem.



Spanky

My Tracker II 12 ga is tapped as Spanky's is from the sounds of it.  Mine however did not have the screws flushed up on the inside of the chamber and in firing the brass and plastic would blow/flow up into these voids and stick the spent hull in the chamber.  I fixed it by filling the voids with JB welld and now all is good.

That said, I recently had a 12 ga pardner in having it cut to a shorty and screw in chokes installed as well as having a scope rail installed.  When I picked it up he had not tapped it for the scope rail as he said it was too thin...funny thing is that we went over that when I dropped it off and I told him to silver solder it if needed and he must have forgot about that...I didn't leave it as it had already taken him a year and I was just happy to have it back and I figure I'll take it somewhere else for the rail...

LM
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Offline MSP Ret

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Re: Drill & Tapping a 12 ga bbl for scope mount?
« Reply #6 on: December 05, 2010, 12:51:15 PM »
No problem at all, see the below post. My gunsmith says it will be safe as well. Not the best, but safe. He says he will not do it that way but has seen and shot many that have been done just as below. I suggest you locktite or epoxy the screws into position after fitting....<><....:)

I've got a 12ga. Pardner barrel with scope mount on it. I just drilled through into the chamber and tapped the holes. I measured the hole depth and ground the screws to the proper length to be perfectly flush with inside of the chamber. After that I polished up the chamber and you can't even tell where the screws are when you look into the chamber. I've fired hundreds of rounds through it without a problem.



Spanky
"Giving up your gun to someone else on demand is called surrender. It means that you have given up your ability to protect yourself to a power that is greater than you." - David Yeagley

Offline getom59

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Re: Drill & Tapping a 12 ga bbl for scope mount?
« Reply #7 on: December 06, 2010, 03:59:53 PM »
My son has a 12 gauge SB1S14 rifled slug gun and it was drilled and tapped from the factory.  This barrel is not the big diameter one that's on Ultra,  it's closer to a normal diameter.