I do love the looks of the wrap-around front sights. But 1) my understanding is that they require reaming to achieve the exact inside diameter to fit the barrel and 2) the current front sight ramp has some grooving/checkering that looks like it was hand-cut and it matches the pattern on the rear sight so I want to retain that.
Crack in Front Sight Dovetail Slot
- Thread starter mrh477
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I do love the looks of the wrap-around front sights. But 1) my understanding is that they require reaming to achieve the exact inside diameter to fit the barrel and 2) the current front sight ramp has some grooving/checkering that looks like it was hand-cut and it matches the pattern on the rear sight so I want to retain that.
Update: Took the rifle over to a friend who welds. No one in town micro welds or laser welds that I could find, and this option was basically free. He said it could be TIG welded but he would have to polish the bluing off around the crack. No big deal. If it is small enough I can touch it up with cold blue, and I'm thinking about rebluing the whole rifle anyway since I'm refinishing the stock. It was re-blued at some point in its life before and the second bluing job was with hot salts I believe. There are a few pieces that are a different color, presumably these parts were not included in the reblue and thus have the original rust blue which I like better anyway.
Anywhoo, we ran into problems TIG welding the piece--kept getting pin holes. It is definitely some type of steel but being 70+ years old and from Germany we cannot know the exact makeup of the metal. That's the only explanation I can think of. Maybe this friend is just a ****ty welder but I don't think that's the case.
So, option 2. Took the rifle to the best gunsmith/machine shop in town and asked the expert. His recommendation was to mill off the entire dovetail slot and cut a new slot. It'll probably end up costing me $60-70 or more but oh well, I want to do this right. The machinist here doesn't have a dovetail cutter small enough (it's a tiny, odd size) so what we're probably gonna do is cut the new slot square, drill and tap a hole through the sight insert and into the ramp, and attach the sight insert via a set screw. There's enough metal on the ramp for the hole to be pretty deep so it should be a solid enough attachment.
So, moral of the story, don't waste time trying to save money. I seem to keep learning this lesson repeatedly.
Anywhoo, we ran into problems TIG welding the piece--kept getting pin holes. It is definitely some type of steel but being 70+ years old and from Germany we cannot know the exact makeup of the metal. That's the only explanation I can think of. Maybe this friend is just a ****ty welder but I don't think that's the case.
So, option 2. Took the rifle to the best gunsmith/machine shop in town and asked the expert. His recommendation was to mill off the entire dovetail slot and cut a new slot. It'll probably end up costing me $60-70 or more but oh well, I want to do this right. The machinist here doesn't have a dovetail cutter small enough (it's a tiny, odd size) so what we're probably gonna do is cut the new slot square, drill and tap a hole through the sight insert and into the ramp, and attach the sight insert via a set screw. There's enough metal on the ramp for the hole to be pretty deep so it should be a solid enough attachment.
So, moral of the story, don't waste time trying to save money. I seem to keep learning this lesson repeatedly.
- Joined
- Dec 19, 2002
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- 22,474
Thanks for updating us on the final outcome.
One of my classmates had as his final project the rewelding of some part. Turns out it was pot metal and could not be welded. He was afraid he had flunked and would not graduate. I told him that the only way he could have gotten it to work was to make an entire new part and the easiest way to do it was to scan it into the computer and CNC it (followed by heat treatment). You went for the easiest route first and when that failed, to the next level. Nothing wrong with that.
One of my classmates had as his final project the rewelding of some part. Turns out it was pot metal and could not be welded. He was afraid he had flunked and would not graduate. I told him that the only way he could have gotten it to work was to make an entire new part and the easiest way to do it was to scan it into the computer and CNC it (followed by heat treatment). You went for the easiest route first and when that failed, to the next level. Nothing wrong with that.
thehobbygunsmith
Member
do not mill it off its not necessary, that front sight is soldered on get the front sight cherry red with torch and knock it off or pull it of with pliers. then get machinist to fabricate new one since you have the piece off and after done just re-solder back on the rifle. trying to mill it off will be more trouble. and more chances to scratch your finish on the rest of the rifle.
I won't be the one doing the milling--I'm leaving that to the professionals. It was the gunsmith's recommendation and I trust him. I'll be rebluing the rifle anyway so a little bit of scratching wouldn't be too big a deal. That said I expect there won't be any damage done. Fabricating a new sight ramp would be easier if it wasn't for the checkering/groove pattern that looks like it was hand-cut. It matches the pattern on the rear sight so I would like to retain that.
Yep, I wish I would have thought about the issue of metallurgy before going forward with the welding idea but oh well. Live and learn. I would imagine it is a common issue on older guns as well as foreign ones perhaps.
HisSoldier
Member
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- Sep 26, 2007
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- 1,330
Having both manual and CNC capabilities I'd mill a new one using a Bridgeport type manual mill from prehardened 4140 from a hand drawing of the original. The real problem for me would be silver soldering the new one back on, it should be done in an oven using silver solder foil and black flux, THAT part I'd farm out. Oh, and if $60-$70 seems high I'd never touch it.
But I'm a machinist, not a gunsmith.
Edit; silver soldering would knock most of the preheat treatment out of it, so there's no sense using Pre heat treated stock.
Blue68f100
Member
There is low temp solder used on guns that would not remove any heat treating.
beag_nut
Member
Very true. It's called silver-bearing soft solder, sometimes available as a foil (or one could flatten some with a hammer instead). You JUST beat me to replying to HisSoldier, by a millisecond!
BBBBill
Member
Brownell's Hi Force 44 -
080-649-301WB
1 oz Hi-Force 44™ Ribbon
$8.99
Quoted from the website - "Flows free and smooth at about 475° F., greatly reducing heating time. No need for cumbersome oxyacetylene setups. Prevents black oxide formation to reduce cleanup time. Provides 14,000 to 28,000 PSI tensile strength. Will not crack under stress as do other low temperature soldering materials. And, a big plus . . . customers report that parts joined with Hi-Force 44 Solder showed no effects when immersed in hot bluing tanks! Use #4 Comet Flux."
beag_nut
Member
Yup, that's one of the candidates. A little low on the silver content, but that's OK. A product called Eutectic is the cat's meow, but hard to get from non-industrial suppliers. The Hi-Force is much less expensive.
BBBBill
Member
I've used it many times with great success. Even though the risk is much lower, to ensure no damage and control the heat spread I pack the bore with heat control paste and build a dam of it around the solder site.
If you weld or solder, chances are the barrel will have to be refinished and part of the rifling may be damaged. BBBill had the right idea, just mill the top flat, cut a crosswise dovetail and install a tad higher sight blade. A bit of touchup blue should finish the job..
As a side note, I never cease admiring the folks who think every problem can be fixed with JB Weld. Shotgun barrel burst? No problem. JB Weld will fix it. Trailer hitch broken? Reach for JB Weld. Cracked connecting rod? JB to the rescue. Tank took a direct hit from a Russky 203mm HEAT round? Apply JB Weld and load up. (OK, I made up the last, but the first three "fixes" were actually suggested on line!) JB and similar products are fine for some jobs, but gluing a shotgun barrel or a cracked connecting rod back together? Come on, guys
Jim
As a side note, I never cease admiring the folks who think every problem can be fixed with JB Weld. Shotgun barrel burst? No problem. JB Weld will fix it. Trailer hitch broken? Reach for JB Weld. Cracked connecting rod? JB to the rescue. Tank took a direct hit from a Russky 203mm HEAT round? Apply JB Weld and load up. (OK, I made up the last, but the first three "fixes" were actually suggested on line!) JB and similar products are fine for some jobs, but gluing a shotgun barrel or a cracked connecting rod back together? Come on, guys
Jim
beag_nut
Member
My only issue with this comment is about "solder", causing damage to the rifling. Not true, will not happen. We have been talking low-temp soft-solder here, nothing above 800 degrees. The higher-temp process is properly known as brazing.
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