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w_houle
March 29, 2009, 05:37 PM
Can you fix holes partially drilled into a barrel that are say 1/4 of a hole off? Is there something to fill the hole and maybe I could re-drill it?

rgitzlaff
March 29, 2009, 06:00 PM
Try JB Weld, that might work. If it doesn't I don't know what will, except for maybe some stainless steel filled epoxy.

hunter11
March 29, 2009, 06:07 PM
Drill a larger hole big enough to have room for the new hole to be all in the plug you put in the big hole. either Tap the big hole or locktite the filler plug. Then be a lot more careful. Dan

Chris_B
March 29, 2009, 06:08 PM
Partially drilled?

I would not use a drill or even a drill press to do the next hole, I'd use a milling machine

ISC
March 29, 2009, 06:14 PM
1) finish drilling the holes in their current location.

2) tap them to the bottom of the hole.

3) use red loctite to set a screw in placein the hole

4) cut of the screw flush with te barrel and file it flat.

4) redrill in the correct location.

madcratebuilder
March 30, 2009, 09:23 PM
1) finish drilling the holes in their current location.

2) tap them to the bottom of the hole.

3) use red loctite to set a screw in placein the hole

4) cut of the screw flush with te barrel and file it flat.

4) redrill in the correct location.

This is really the best fix, any thing else is a band aid.

James K
March 31, 2009, 01:26 PM
The best fix is to find an expert with a heliarc welder who can fill up the holes and use a heat sink (wet cloths) to keep the heat from affecting the barrel. Then redrill, using a jig or a milling machine. With a bit of luck if you are installing sights or a sight base, the work will be covered and you won't even have to reblue the barrel.

When I was working as a gunsmith, we got that problem about once a month, as people who didn't want to pay for a proper drill and tap job used a hand drill or tried to have it done at a local garage.

P.S. JB weld won't hack it.

Jim

grymster2007
March 31, 2009, 02:03 PM
Yup; TIG weld them up, then re-drill in proper location. Tapping, then plugging with a screw would likely work also. I'd avoid JB Weld.

James K
March 31, 2009, 07:59 PM
Maybe someone can enlighten me, but what is it with JB Weld? I have used it and it is just another glue with metal in it, like a half dozen others. It is absolutely NO substitute for welding in any situation requiring any strength.

But for some reason, folks attribute to it some kind of magic. I remember one poster who had a barrel crack and was advised to use JB weld to hold in 40 or 50 k psi!

Those epoxies and "welds" are fine in their places but they are not hardened steel. They will drill and tap, but the threads won't hold under any significant strain.

Jim

grymster2007
March 31, 2009, 08:25 PM
Bingo, Jim. I tried it a couple times as a young pup, but found no good use for it. I like metal.... real metal.

HiBC
April 1, 2009, 01:55 PM
I agree the JB idea is not good.When it doesn't work,it makes life harder for your tig meister.

I would also agree with a toolmaker grade tig expert being one good option.

I will offer another option.The end result you want is a base screwed on the gun,and the hole in the base does not line up.It may be easier to move the hole in the base to suit the hole in the receiver.

There are a number of ways to do this,from blank gunsmith bases to milling the base to accept an insert to welding the hole in the base.

Myself,I think I would avoid more trauma to the rifle if you have a good tapped hole.Is it possible this was done on a mill with the old reverse backlash,or .100 error,or a slipped dial? Maybe the hole is centered on the action,in line,(y axis) but an error occured in the x-axis?.

You can try 2 or 3 times on bases,till something works,without doing anything more to the rifle.

hunter11
April 1, 2009, 02:32 PM
I have to agree with Hibc reworking the Base is the best fix. Dan

grymster2007
April 1, 2009, 09:54 PM
I have to agree with Hibc reworking the Base is the best fix. If'n ya can stand knowing that the hole is off location. :)

madcratebuilder
April 1, 2009, 10:04 PM
I wouldn't hesitate TIG'ing a hole in the receiver, but I would be very careful about TIG welding a hole in the barrel. No matter how well you control the heat you well effect the grain structure of the steel.

James K
April 3, 2009, 09:58 PM
There are several alternatives, including working over the base. If only one hole has been drilled, you can simply move the base so the old hole is covered and re-drill. This gets trickier if all the holes have been drilled crooked because the rifle barrel/receiver will look like swiss cheese if the base is removed.

Another possibility is using a different base with different hole spacing. Just inserting a screw and redrilling will usually work if you are using a milling machine or a very stiff jig and if the screw is soft and the drill is stiff. Otherwise, the drill will try to follow the edge of the screw, with bad results.

If this is a personal project, anything goes that works. But a professional gunsmith has a problem. If someone else did the work, he needs to have a talk with the customer and discuss options. If he goofed, the best thing is to fess up and offer to repair or even replace the gun.

I remember a Winchester Model 71 (.348 Win.) that came in for sighting in. I happened to notice what looked like the edge of a hole peeking out from under the side mount. I asked the customer to wait while I pulled off the mount. There must have been at least 15 holes in that receiver! The "gunsmith" who put it on couldn't get it sighted in, so he moved the mount, still couldn't get it sighted, and so on. The customer finally took it back and brought it to us to sight in.

The last I saw of the customer, he was going out the door, red-faced and steaming, headed for the other shop. I never heard of that gunsmith being murdered, so I guess it didn't get that far, but it does illustrate what not to do and not to panic and start doing irreversible things.

Jim

longrifles, Inc
April 3, 2009, 10:55 PM
Tig the holes.

A MIG will do it as well. When at Nesika we'd have an occasional woops during barrel engraving (using a 4axis CNC) by having a bad offset and it'd result in a carbide center drill committing suicide.

A quick zap and sizzle and five minutes with a file and a belt sander saved the day. Never saw any difference on paper either.

Cheers and good luck.

Last note. If you intend to blue it, then you will see the spot because of the difference in material from the filler rod/wire. Just be aware.

madcratebuilder
April 4, 2009, 09:26 AM
A quick zap and sizzle and five minutes with a file and a belt sander saved the day. Never saw any difference on paper either.

Apparently I'm overly concerned about the heat issue. I can't say I have ever did any welding on a barrel and you folks have much more experience that I do. I guess I won't hesitate to fix any boo-boo's I do.:)

ISC
April 4, 2009, 12:05 PM
Apparently I'm overly concerned about the heat issue. I can't say I have ever did any welding on a barrel and you folks have much more experience that I do. I guess I won't hesitate to fix any boo-boo's I do.

I wouldn't worry about it as much on the reciever as I would on the barrel, but I worry enough about it to avoid it if possible.

hunter11
April 4, 2009, 12:57 PM
I owned my own highly precision Engineering and Manufacturing business for 25 years so I feel I know of what I speak. Do not even think of JB Weld do not weld in any way. Either modify the mount or Drill a larger hole and plug it. Then drill the hole inside the plug where it belongs. Just friendly advise. Dan

HiBC
April 4, 2009, 02:51 PM
The one and only time in my whole experience in the shop that I ever had an extra hole in the wrong place(due,of course,to "concurrent engineering")

All I did was put in a plug screw,get out the letter stamps,and stamp OIL next to the hole.No problem.

I recall a friend adapted a Ruger 1/4 rib to another single shot and had to move some holes a bit.He bored thru the base on the new location with an end mill large enough to clean the off location hole,then counterbored the hole.He made a shouldered bushing to press in the new hole,complete with a hole and counterbore for the screw.It looks fine and works well.

I have seen some pretty amazing welding done in the bizz of moldmaking.

The word "microwelding" comes to mind.There is an outfit in Wisconsin saved my heinie once,but I don't know their name.

Unclenick
April 4, 2009, 04:11 PM
When I was working as a gunsmith, we got that problem about once a month, as people who didn't want to pay for a proper drill and tap job used a hand drill or tried to have it done at a local garage.


Heh, heh. Bubba and his Black & Decker can be a gunsmith's bread & butter. Almost as helpful as his brother who owns a Dremel tool.

The plug screw and re-drill fix needs the warning tossed in not to use a hardened set screw as the plug. Ideally, the steel should match so the next attempt at drilling doesn't walk the drill toward the softer of the two metals. This can apply to a weld-up, too if the filler is much different from the original material. A jig with correctly spaced drill guides is best for preventing the walking problem on the next go-around.

If you wind up needing to drill with an end mill, be sure to buy a cutter called an end cutting end mill. End mills without that designation won't cut down in the center.

James K
April 4, 2009, 06:28 PM
I sort of alluded to that about the screws, but it needed to be clarified, and you did it very well. Some of those plug screws and mount screws are very hard and anything but a stiff carbide starter drill will try to wander.

Jim

HisSoldier
April 4, 2009, 07:57 PM
He said the hole was 1/4 of a hole off. tapping it and plugging it won't work under those circumstances unless you drill and tap it large enough so that the new hole is entirely within the plug. With 1/4 of a hole off center you would end up with a tiny crescent moon shaped piece on one side, and it won't stay there if that's the case. In my work I have to fix this kind of thing sometimes. I'd take it to a mill with a DRO, use a center cutting endmill to center the hole oversize where it should be, which should still only be 1 1/2 times the original size, then drill that hole carefully, tap it with a fine threaded tap and drive in a threaded plug with permanent loctite. Then your new hole of the correct size will be centered within that, essentially you are making a threaded insert in place. Make sure and allow the loctite to set up well before drilling and tapping the plug. I've done this many times both with offset oversize plugs and with centered plugs, centered is better. In either case if done right it will never come out.

Or,,,, tig weld it. :)

dahermit
April 4, 2009, 08:05 PM
...use a heat sink (wet cloths) to keep the heat from affecting the barrel...If one needs to prevent heat from affecting other than where one is welding, one should invest in the stuff that is made for the job and to which I can attest is better than other metods. To wit: Brownells Heat Stop Heat Control Paste, stock number 083-012-100

longrifles, Inc
April 5, 2009, 09:39 AM
Lets do a comparison.

We'll look at a crankshaft in a circle track/road racing engine and a barrel.

The crankshaft accelerates and decelerates a 2500 pound car for the duration of the race. The dynamics of an reciprocating engine are pretty violent as one journal accelerates during the power stroke and the other seven struggle to keep up, then reverse the process during deceleration. Never mind that it also provides the motion for the camshaft/distributor and that alone consumes over 300hp when operating above 7500rpm.

These cranks develop cracks over time, regardless of how generous the radius is along the journal fillets. These cracks are welded, reground, chrome plated/nitrided, and then it goes right back into service.

Unless your a barrel on a machine gun deployed to Afghanistan your barrel with the buggered hole has a life that is quite easy by comparison. TIG/MIG the hole and forget about it. If your really that worried buy a copper rod that slips in the barrel, some heat exchange paste and stick it in the barrel for a heat sink. Overkill IMO but if it makes you feel good go for it.

I've done this repair and it works so long as the person running the welder doesn't turn the hole into Chernobyl or 3 mile island. It's worked on 1000 yard palma guns that have competed in world championships to magnum caliber elk guns. All of which were built over the last ten years and are still in service.

rbb50
April 5, 2009, 10:25 AM
I used a DC inverter welder drilled and cleaned the holes out heat sinked the barrel and filled the holes back in with a nice weld.

Grinded them back smooth with a demel tool and cannot even see where they were now.

You can buy a flux wire welder or even a DC inverter stick welder for cheap now days and with some practice (A lot of practice I should say) on a bunch of scrap metal before you know it welding stuff onto a receiver or barrel will be no problem for you.

Having a stick welder and a flux wire welder has been one of the best investments I have ever made and both only cost about $300 including a auto helmet, gloves and a bunch of wire and 15 pounds of sticks or so.

What is funny once I got them all of a sudden people bring me all kinds of good scrap metal for free I can build all kinds of stuff out of.

Check out this heavy duty target stand I’m still working on now to add some more targets.

http://raybb.com/tstand.jpg

Boards slip into the top for easy change out and stapling targets onto and the steel targets are so heavy they will probably stop a tank shell :rolleyes:

That one steel target hanging on the left weighs 52 pounds LOL

All of the metal used in them was being thrown away unless I wanted it so I recycled that metal for a good use :D

I just picked up 60 feet or so of 1/4" thick x 1" angle iron the other day so I'm having fun with the welders today :D

rbb50
April 5, 2009, 10:48 AM
I should have added if you are going to try that be sure to practice welding up a bunch of small holes on some thick steel stock first so when you put that weld on the reciever or barrel you know exactly what to expect.

Filling a little hole with a weld is not just a 1-2-3 operation unless you have had a lot of practice before hand.

I remember when I first got the welders I was going to do that then stopped myself for some practice before hand to find out I had to drill about 20 holes in that scrap steel stock as a way to get that weld just right.

Then when I did the weld to fill the reciever holes they were perfect :D

Practice made perfect go figure :p

ISC
April 5, 2009, 11:13 AM
If my welds were that bubble gummed up I would be embarassed to show them on a public forum.

It's easy to burn rods. It's even easy to run a wire welder. Anyone can have a welder, but not everyone can be a weldor. TIG welding is as much an art as it is a skill. Unless you are an experienced weldor that understands the effects of crystallization, and heat treating, welding a barrel can be dangerous. I would caution a beginner to use the tap and plug method instead.

His Soldier brought up a good point about the hole size. Drilling it larger and then using a smaller hole inside the plug would probably make it stronger. I think that 1/4 of the hole diameter off isn't too much to fill with the original size plug, but anything larger than that would definately be better to use a larger size plug.

totalloser
April 14, 2009, 12:21 AM
+1

I can't help but cringe at the thought of buzzing on a barrel. Maybe on a .22 or something, but you WILL anneal the metal. I don't care how clever or awesome of a welder someone is, that spot will get annealed. That makes me nervous, personally. I wouldn't even CONSIDER buying a rifle that had a weldment on the barrel, personally, would you?

Shooter_454
April 14, 2009, 07:07 AM
I would try this

http://www.youtube.com/watch?v=6YaSf9GhEkM&feature=related

rbb50
April 14, 2009, 07:41 AM
If the barrel has been heat treated properly you will never have a problem.

I have shot over 200 rounds out of the 7.7x58mm I fixed and it hits dead center bulls-eye every time.

I'm sure not going to sell that rifle when it is that accurate and even if I did someone would sure have a nice one.

microfusionwelding
May 4, 2009, 11:19 AM
This type of welding is our specialty saved many parts over the years.:)

check us out

www.microfusionwelding.com

dipper
May 4, 2009, 07:29 PM
I've been a toolmaker/moldmaker for over 32 years and have repaired a few things with the problem the OP described.
Here is what I normally do and it has worked out fine.

Make a plug of the same type metal you are repairing.
Make the plug .0002 to .0004 oversize...bigger than the hole you want to fix.
Make the plug about .015 shorter than the depth of your hole.
Heat the area with the hole up---use a hairdryer, heat lamp etc.
It doesn't have to be hot just fairly warm to the touch.
Put your plug in the freezer for half an hour.
Tap the plug in the hole and it should sit down from flush about .015.
Have someone that REALLY KNOWS how to tig weld fill up the remaining .015.
Smooth off with file and sandpaper till your happy---it will be invisible if done correctly.
Drill and tap any darn place you please, the repair won't affect anything if done properly.

smoakingun
May 4, 2009, 10:13 PM
this is going to sound dumb, but if he is only a quarter of a hole, and for probably a 6 screw, he's .025" off, so why not change the hole in the mount?