New Birthday Present Mauser

[Deep Six]

Today is my birthday and my wife did pretty good this year! - A Yugo 24/47 in 7.92x57mm. It's one of the "Special Selects" from Samco. The bore is the nicest I've ever seen on a surplus WWII gun. It's bright and flawless with nice sharp rifling - it basically looks brand new. The rest of the action checks out excellent as well, and the bluing is dang near 100% with no pitting or rust anywhere, even beneath the wood line. The stock has an average surplus rifle finish but has a weird twisted warp at the muzzle end. Basically the bayonet lug is at about 6:30 instead of 6:00. I've got a call into Samco and they are trying to find me a spare stock for it. If they're not successful, I'll find another one on gunbroker or something. The only issue is that the front site band came unsoldered from the barrel. So I'll either have to solder that back on or possibly just drill a small hole in the bottom of the band, spot weld it to the barrel, grind flush, polish, and cold blue. Right now I'm thinking the spot weld option sounds easier.

My plan is to make this my dedicated cast boolit rifle. I already load 8x57 for a commercial Husqvarna so I've got dies, brass, etc. I slugged the barrel on the new Yugo and it's 0.324 in the grooves and 0.3125 in the lands. Perfect! :razz: I didn't get a chance to slug the chamber but I've got a supply of 1950's Yugo 196 gr ball ammo and that chambers without hesitation. I mic'd the Yugo ball ammo and the bullets are 0.324 for at least 0.200" past the case mouth, so I should have ample throat to work with for cast boolits.

[Deep Six]

I started designing a mold. I think 175 gr would be about right. Here is what I came up with using Mountain Mold's design tool. This is my first attempt at designing a bore-ride design so I welcome any feedback.
84599

[Frank46]

Tap the front sight blade out of its base. A lot of mausers have a set screw under the blade as well as being soldered in place. Frank

[Multigunner]

Hot bath bluing can dissolve soft solder.
If the rifle was reblued by someone unfamiliar with the Mauser they may have blued the barreled receiver without first removing the front sight.

I would solder it back using HighForce44 solder, its the strongest there is.
Clean away any remnants of previous solder first.

There a chalklike material you can get for coating any of the barrel surface that you want to prevent solder sticking to avoid damaging the finish. I have some but have never had to use it.

[Deep Six]

Well the last time the gun was worked on was probably the late 40s when it was re-arsenaled and then submerged in cosmoline for the next 60-something years. I'd like to think the people who were re-arsenaling them knew a thing or two about Mausers....

I've never tried high temp solder and I'm not sure that I want to try my luck at it now. I' m pretty sure I could use my MIG setup to get a nice strong spot weld between the front site band and the bottom of the barrel without damaging the barrel. I little sanding and cold blue and it'll be plenty good enough for an war-horse cast boolit working gun.

[MtGun44]

IMO, any weld on a barrel damages it for certain. You will note that NO gunmaker
welds on a barrel. Use regular soft solder like Mauser did. I lasts just fine.

Bill

[Deep Six]

The stuff from Menards that I use to sweat copper water pipes together? If that will hold, I'll give it a try...

Also still looking for feedback on the bullet design I posted.

[MtGun44]

Yes, if you bought it 5-10 yrs ago. If recently, it has a substantially
higher melting temp and doesn't flow as easily, they removed the
lead.

Bill

[Deep Six]

The plumbing solder I have is lead free (it's 95/5 tin/antimony). The electrical solder I have is the good old 60/40 lead/tin stuff. I can still buy both types at the store today. Is there any reason not to use the electrical solder?

[MtGun44]

No, that is what Mauser used - "soft solder" (63-37 actually is the optimum mix although
60-40 is the common name, eutectic solder, lowest possible melting temp from a binary
tin-lead alloy - the eutectic point). Get the surfaces tinned if they are not
already and then assemble and feed in a touch - done! Goodsteel has a nice thread on
getting steel to tin if you need it. If this is the old stuff, it should still be tinned.

Bill

[Deep Six]

OK. Any thoughts on my bullet design?

[MtGun44]

Don't pretend to have the knowledge of rifle boolits to criticize other's designs. Still
learning about rifles. I have some stuff that works for pistols, and am comfortable there,
but not so much with rifles. A few particular rifles have been loaded with a few different
boolits with success, but not enough breadth and depth to feel like anything but a
student of boolits in rifles.

Ask Ben if he has any info for you.

Bill

[Deep Six]

Just checked underneath the front site blade. Sure enough there is a set screw, and even a small hole in the top of the barrel to engage it. For some reason the screw had a flat point that didn't fit in the hole in the barrel. I removed the set screw and chamfered the point. Now it fully engages the hole in the barrel and the sight is rock solid. I'll see if it holds up to recoil. Perhaps I won't have to mess with solder or welding after all.

[tdoor4570]

If you deside that you would like to put a scope on that Yugo I have a way of mounting a LER handgun scope and not change or damage the rifle at all. Just get a hold of me and we will talk on the phone. Its real easy to do tdoor4570@bresnan.net

[ebner glocken]

IMO, any weld on a barrel damages it for certain. You will note that NO gunmaker
welds on a barrel. Use regular soft solder like Mauser did. I lasts just fine.

Bill
How did they get lugs on thompson contender barrels? They look TIG welded to me.

Ebner

[MtGun44]

If it is welded, it will typically be done to a blank and then heat treat or at least normalize
and stress relieve the whole assembly before doing any significant machining on it. Welding
messes up the strength locally and warps stuff. If you do it early, then re-heat treat and
then do your machining, it can work because you get the strength back and then work out
the warpage (let it warp) and then machine it straight. Welding on parts that are fairly
far done will mess usually them up.

The are some exotic welding methods out there now that keep the heat extremely localized,
like electron beam welding, that may work if done really carefully. Normal arc or gas welding
(TIG, MIG, oxy-acetylene) would not be good choices, in general, unless there was going
to be "corrective" action afterwards. Of course, there may be some exception out there, just
to make me squirm. I stand by the basic comment - with maybe a clarification - something
like "it is very tricky to weld on something like a barrel, you are likely to cause a lot of
problems, and it is never (rarely?) used by manufacturers". E-beam welding can punch in
deeply yet have a very small amount of excess heat added, which minimizes warpage.

I'd actually like to know what TC does do with those barrels, I have never examined a Contender
closely, and I think I know what I would do if I was in charge of production, but there are some
smart engineers out there and maybe they have a special trick.

Bill

[ebner glocken]

No insults intended, wasn't trying to "make you squirm" Mostly I was wondering if NO maker welded on their barrels what kind of bonding process they was using that looked like TIG welding.

It has been my experience that if the heat affected zone is held to a minimum and not close to that is needed to be heat treated (temp greater than 250*F), all will be fine. IE, you can weld a lug to a pipe w/ very little warping if coolent is run through it while welding. I am curious if thompson is doing this or simply welding lugs then heat treating....... Or of course using some process that none of us are familiar with.

Ebner

[Multigunner]

Some older front sight bases look like they were either cut from the blank or welded on but were actually brazed on. Even the heat of brazing could cause problems if not done properly.
Some shotgun barrels had the lug brazed or silver brazed in place.

A seam welded tube can be stress relieved to greatly reduce chances of it splitting along the seam under high pressure.

[MtGun44]

No problems, I made a slightly overbroad statement. In general, welding is
not friendly to finely finished parts due to heat oxidation of finished surfaces,
warpage and structural integrity damage due to the local softening.

It is not impossible to weld guns but typically the heat causes more trouble than
it solves, so most avoid it. E-beam welding could be an exception if engineered
correctly.

Bill