Looking for advice regarding silver soldering scope bases. I recently bought a rifle with some odd European bases on it. Tried to remove them and got one screw out of each base. Drilled the head off the others and tried to remove them. No luck. Tried a propane torch to see if it was epoxy or low temp solder. No luck. Took it into Williams Gunsight to see if their smiths could remove them. He told me the bases were silver soldered on and that the receiver and barrel had their temper destroyed and had effectively been annealed and the gun was unsafe to shoot. What say the smiths on here? I don’t want to shoot it if it’s unsafe. Thanks,

Old70

How did the Williams 'smith determine that the action's temper had been destroyed ? Was the action's Rockwell hardness checked ? That's the only way to determine if the action's hardness/temper had been "destroyed". I would have the Rockwell hardness checked before arriving at the determination that the gun was unsafe to shoot.

I think there was an assumption made. Said that the steel had to be brought to 1700+ degrees for the solder to flow, and that was too much for the steel. It might have been smith-ese for ‘I don’t want to deal with it’

Old70

I believe you're right about not wanting to deal with it.

Source of the Information

Throw some heat stop around it, heat the rings till they pop and then smack the receiver with a temp reading. Over 1400 I'd be doing some investigating.....under, I'd rock on. It's notice you're soaking the lugs with that heat.

Thanks, I’ll see what I can do.

photos? I have had some experience with old claw mount type bases

Evnin, not that it helps much but some silver solder melts at 450 deg. and holds like chit to a screen door. Some knife makers use it to install guards on the knives. Trouble is ya don't know what solder was used. Bill out. 🐾👣🐾👣🇨🇦

Took it to an experienced local smith, he tested it and determined it was silver brazed, had been effectively annealed, and would need to be re-heat treated and re-blued once they come off. He quoted a decent price so I told him to go ahead. I'll let y'all know how it comes out. This will give me time to work on the stock while I wait.

O;d70

These things are handy around a gun shop, answer many questions. Bought it last year, should have bought one 30 years ago.








Olympic BBK action shown. 34 on the Rockwell C Scale. I have found many surprises with some M98's and especially with the 36 Mexican.

Mark X, 53 Rockwell C




Post 64 Classic. 47 Rockwell C.




Ruger M77 Tang Safety. Almost 49 Rockwell C .

The numbers tell a tale.


.

So you figure the receivers are made from 4140 steel then ?

No. Only a few. M98's are carbon steel, usually case hardened, this is why they are usually 20 or so on the C scale. I will post some photos of 98's later.

Mark X are generally understood to be 4140.

M70 and Ruger, generally 4140.

As hardness of 4140 is directly related to the tensile strength, it is interesting to know just how strong your receiver is, if made from 4140.

The post earlier about using a Santa Barbara action for a 338 Lapua got me to post up some hardness photos.

Edit: I have a Santa Barbara action, I will test it for hardness and post results.

Dan Lilja had an article about bolt thrust on his web site from some of the big cartridges like the 338 Lapua, his article says to not use a M700 for this cartridge, so some thought is in order when selecting actions for this one.

I have build a 338 Lapua on a CZ550, it works great.

Corona M98. 24 on the Rockwell C scale.

The problem with most Mausers is we do not know what the steel composition is. So we cannot accurately predict the strength as we can with a known alloy such as 4140. Tread with caution!

Hmm. This one was a surprise. Santa Barbara action. 26 on the Rockwell C scale. Expected lower.

The funny tape wrap on the barrel covers a strain gauge for pressure testing.

If the steel type in Mausers is unknown,
How do they retreat?
Or is it a simple quench, drawback, and hope it's what you wanted?