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725
03-19-2022, 08:50 PM
I'm trying to un-Bubba a used rifle I've purchased. Mauser 98 action and our hero D&T'd the receiver a little off center. Question: Can the old holes be welded shut in preparation of re-drilling for a new base? My concerns include the heat treatment of the receiver. I don't want to affect the lug area which, if altered, will lead to future problems. I don't have any particular objection to just re-drilling in as much as the prior holes will be covered by the new base, anyway. Any thoughts? Also, any leads on a good one piece base or even a two piece if I cn find one that will allow the proper scope placement. I will be using a Vortex 4x12 and that scope has a very little in the way of extra leeway to move fore or aft in the rings.

Appreciate any info on this one.

Alasgun
03-19-2022, 10:08 PM
As a Machinist (retired) for over 4 1/2 decades; here’s how i see it. It can be welded but done properly it will probably cost you a bit. However, depending on how far off center it is; the easiest repair would be to oversize the buggered holes by picking up the the center of the action (indicating) and use an endmill to cut the new holes to the tap drill size. Then tap to the next size screw and move on. If the error is not too great that would be the easiest. At best you may have to also open up the recess in the base to accept a larger screw head.

If it’s off more than .010/ .015 thousandth’s you may have to get creative. If you try to use an over size drill it will follow the original holes and you wont gain anything but a bigger mess.

LAGS
03-19-2022, 10:11 PM
I would rather not weld on the front ring.
The rear isn't that important for the heat treatment like the front half of the receiver.
I had a receiver that was drilled off center.
So I welded up the scope base and offset the holes to match the receiver.
Worked good , but that scope base only fits that rifle.

725
03-19-2022, 10:36 PM
Thanks fellas. I can see both ways as viable. I never thought of an end mill drill. That could easily solve the issue and just move up to a #8 screw. No problem re-drilling the base to accept the #8's. Appreciate your answers. 725

Winger Ed.
03-19-2022, 10:38 PM
I'd get a steel scope base, weld up its holes, then re-drill them to fit the rifle.

Alasgun
03-19-2022, 10:58 PM
That works too!

samari46
03-19-2022, 11:58 PM
Burrie makes a set of rings with the inserts off center. Comes in different sizes. Might be cheaper than having to weld and redrill. Frank

Scrounge
03-20-2022, 12:09 AM
I would rather not weld on the front ring.
The rear isn't that important for the heat treatment like the front half of the receiver.
I had a receiver that was drilled off center.
So I welded up the scope base and offset the holes to match the receiver.
Worked good , but that scope base only fits that rifle.

What do you think of Loctiteing spring steel screws in place of the original screws, and then relocating and re-drilling & tapping the new holes for the correct sizes? High-strength Loctite.

Bill

45DUDE
03-20-2022, 12:13 AM
I had a 22 with offset holes. It had a double base. The front base was close and I ordered an adjustable for the rear and when I installed the scope it looked to be in the middle and plenty of scope adjustment.

LAGS
03-20-2022, 12:31 AM
I have filled the holes on receivers that were drilled in the wrong location with screws and then filed them flush.
But most of the time.
The holes for the new mount are so close to the old wrongly placed holes that it makes it hard to redrill and retap without overlapping the holes in the old screw filler screw.

indian joe
03-20-2022, 02:06 AM
work on the mount base not the rifle

plenty different ways to get this

endmill to take out the old holes (oversize and centred on the dodgy holes in your reciever) then turn a couple little bushes so your original screws fit
can even turn those little bushes off centre to better locate it all then when all set - silver solder them into the base

John Taylor
03-20-2022, 04:53 AM
I get a couple a year that have been bored off center. I set them in the mill and bore a new hole that is over size enough to clean up the old hole but centered. I then tap the hole and screw a plug in then drill and tap the plug in the right spot. Most will clean up with a 1/4-28 plug. The plug is installed with loctite. after the scope base is installed you can not see the repair. The only ones that get welded are Winchester model 70 pre war rear bridge which are not supposed to have a hole. They require a scope base that uses the side holes on the rear. Collectors do not like them with holes that were not factory.

country gent
03-20-2022, 06:35 AM
Tapped holes off location or worn out dowel holes got sleeved and redrilled and tapped if needed. Hole was taken out bigger a plug turned and threaded then cleaned and degreased the sleeve either pressed or threaded in with locktite and redrilled on location. If possible we used allen head cap screws for the plugs it was a good tough material. The enddmill is a goo way to move the hole on to location with out having to bore it. Cutter grind would grind dull carbide endmills down to tap drill sizes for us.

725
03-20-2022, 08:07 AM
So many ways to go. Thanks again, fellas.

JSnover
03-20-2022, 09:13 AM
Tapped holes off location or worn out dowel holes got sleeved and redrilled and tapped if needed. Hole was taken out bigger a plug turned and threaded then cleaned and degreased the sleeve either pressed or threaded in with locktite and redrilled on location. If possible we used allen head cap screws for the plugs it was a good tough material. The enddmill is a goo way to move the hole on to location with out having to bore it. Cutter grind would grind dull carbide endmills down to tap drill sizes for us.

^^ That! The easiest way to move a hole is to fill it first.

elk hunter
03-20-2022, 09:36 AM
I get a couple a year that have been bored off center. I set them in the mill and bore a new hole that is over size enough to clean up the old hole but centered. I then tap the hole and screw a plug in then drill and tap the plug in the right spot. Most will clean up with a 1/4-28 plug. The plug is installed with loctite. after the scope base is installed you can not see the repair. The only ones that get welded are Winchester model 70 pre war rear bridge which are not supposed to have a hole. They require a scope base that uses the side holes on the rear. Collectors do not like them with holes that were not factory.

(+ 1)

atr
03-20-2022, 12:46 PM
Burris makes a set of rings with the inserts off center. Comes in different sizes. Might be cheaper than having to weld and redrill. Frank

This has worked well for me due to an off-center set of base mount holes. Totally cured the problem

uscra112
03-20-2022, 01:31 PM
I've fixed mis-drilled holes in a barrel using the John Taylor method. About to do another.

DougGuy
03-20-2022, 01:38 PM
then tap the hole and screw a plug in then drill and tap the plug in the right spot. Most will clean up with a 1/4-28 plug. The plug is installed with loctite.

I don't know if you have ever heard of Fluid Weld but it's a fluid electrochemical bonding liquid that they use to hold the tiles onto the space shuttle. Withstands 3000F, bonds dissimilar metals to the point that total destruction will occur before it loses the bond. This is some BAD BAD STUFF buddy, I am telling you!

It is possible to bore a clean hole and tightly fit a dowel into the hole with fluid weld, no threading needed. You won't get the dowel back out without drilling it out. Heat won't loosen the bond.

A single 2oz. bottle lasts me a lifetime. Worth EVERY PENNY of the $30 price! Loctite of any variety cannot begin to come even remotely close to the bond this stuff creates.

297871

https://shop.silver-seal.com/storefrontCommerce/itemDetail.do?item-id=2318&order-quantity=1&item-index=0&customer-item=30333&order-uom=EA&warehouse-id=25&item-number=30333

bigdog454
03-21-2022, 01:07 AM
have used Taylor's method. works good.
BD

Der Gebirgsjager
03-21-2022, 11:34 AM
Take a look at Millett adjustable bases and rings.

DG

LAGS
03-21-2022, 05:05 PM
I wanted to coment on Mr Taylor's suggestion on drilling out the misplaced hole and tapping it for a larger threaded insert that will then get properly redrilled and tapped.
I have done this before , and it works great.
It also gives some people the option to do things themselves.
I had several Tangs for TC Muzzleloaders where someone tried to drill a hole for a tang sight.
They were either off centered or the screw was tapped at the wrong angle.
So I drilled them out to a 5/16 - 24 bolt and then drilled and tapped the tang correctly.
Also , for those that do not have a welder.
You can drill out the hole in the Scope Base for a larger tapped insert.
Then redrill the mounting hole in a location that works to align the scope properly.
Doing the scope base option saves you from having to refinish the receiver on the rifle.

725
03-25-2022, 10:25 PM
Never heard about "Fluid Weld". I can see applications in addition to this problem. Thanks. Thanks to all.

copperlake
03-27-2022, 01:16 AM
I wanted to coment on Mr Taylor's suggestion on drilling out the misplaced hole and tapping it for a larger threaded insert that will then get properly redrilled and tapped.
I have done this before , and it works great.
It also gives some people the option to do things themselves.
I had several Tangs for TC Muzzleloaders where someone tried to drill a hole for a tang sight.
They were either off centered or the screw was tapped at the wrong angle.
So I drilled them out to a 5/16 - 24 bolt and then drilled and tapped the tang correctly.
Also , for those that do not have a welder.
You can drill out the hole in the Scope Base for a larger tapped insert.
Then redrill the mounting hole in a location that works to align the scope properly.
Doing the scope base option saves you from having to refinish the receiver on the rifle.

To riff on this: drill old holes the size of a stud that is oversized to be DRIVEN into it, Countersink a tad with the stud proud. Dance over with TIG, making sure to get a good fill around the countersink. There will be no voids as with threading and little heat problems if an aluminum shank is turned to the bolt diameter as a heat sink. The forward hole isn't gonna get hot enough to cause a problem. I use a common penny nail for the stud.

pietro
03-27-2022, 09:42 AM
Take a look at Millett adjustable bases and rings.

DG

This....... Millet rings will compensate for off-center holes w/o doing anything else besides swapping out the rings.

725
03-27-2022, 10:22 AM
Life, being what it is, I haven't been able to move forward yet. I did mount some Burris "Insert" rings but they were way to high over the bore. Had to lift my face off the stock and that isn't something I'm willing to do with a hunter, which this one will be. Many thanks to all. As the weather breaks and before hay season, I'll be on this one for sure.