Model 70 7mm question

[Listener]

Hello shooters,

I have a 1953 Winchester Model 70 Super Grade. The barrel is stamped "7MM VINCENTS". There are no other markings other than the Winchester stamp. Vincents was Vincent Roux's gun shop in Bakersfield, CA. I believe it to be chambered for 7X57 Mauser, but before I go shoveling in that cartridge I'd like to verify I'm correct. It can't be 7mm Win Mag, as that cartridge wasn't invented yet, so 7X57 seems like the best guess. Any thoughts?

May your groups be tight,

Listener

[T. O'Heir]

A new guy. Howdy.
Winchester stamped on the barrel?
Best you have a chamber cast done. It's a DIY thing if you buy the cerrosafe from Brownell's. The half pound bar will be plenty. Still kind of pricey even though it's reusable. You need a casting pot too. And there are lots of How-to's on-line.
https://www.brownells.com/gunsmith-t...y-prod384.aspx

[Jim Watson]

It can't be 7mm Win Mag,

Sure can't, there is no such thing, although Winchester eventually made 7mm Remington Magnums.

You need that chamber cast, Mr Roux might have fancied himself a wildcatter.

[Nathan]

You might look at the bolt face first. Bolt face and bore diameter may get you close enough the guess accurately.

[old roper]

Calif. could be 7 Wby case if bolt face is for mag.

[Jim Watson]

Time's right.
Not to mention all the Weatherby Wannabes. Didn't he have a patent on the shoulder?

[Paul B.]

Just because the rifle was was originally made in 1953 doesn't mean it was not rebarreled or rechambered to something else later on. Just a thought but I'm thinking the 7MM Vincents is a wildcat cartridge that Mr. Vincent Roux dreamed up. A chamber cast by a competent gunsmith is IMHO definitely in order and necessary. If it does turn out to be a 7x57, you're a winner. If a wildcat, well that would be up to you should you want to have custom dies made up and then try to figure out what to load regarding brass and powder charges. If an uncommon wildcat, it might actually be cheaper to just rebarrel the rifle to something you would rather have.
Paul B.

[Doyle]

Let's assume this is some kind of odd-ball wildcat. Rather than rebarrel, couldn't he have it rechambered by setting the barrel back and cutting a new chamber?

[taylorce1]

Originally Posted by Doyle

Let's assume this is some kind of odd-ball wildcat. Rather than rebarrel, couldn't he have it rechambered by setting the barrel back and cutting a new chamber?  

Maybe, maybe not. It depends what the original chamber is in and if the new cartridge will clean up the old chamber. Get a chamber cast.

[Crankylove]

You might look at the bolt face first. Bolt face and bore diameter may get you close enough the guess accurately

Everybody should do as they think best.

But, for me, if it was my rifle, and my face a few inches from that chamber, I’d spend the time/money to find out for sure rather than just guess.

[Scorch]

Bolt face and bore diameter may get you close enough the guess accurately.

So many reasons that is a bad idea. I could relate a story to you about a pre-64 Model 70 in 284 Win that someone fired 7X57 ammo in, but it's not pretty. Yes, the owner "assumed" it was 7X57 instead of paying for a chamber cast.

[std7mag]

By all means, get a chamber casting done!!
I find it odd that the barrel has Winchester stamped on it, but not the original chambering.
You may want to remove the stock, so you can see if there is anything stamped under it.
As in the barrel was turned down, and the original stamping is now on the bottom.

Lots of wildcatting done in the 50's. Could be some form of 30-06 necked down, with an unknown shoulder.
7mm-06 was around long before Remington adopted it as the 280 Rem.

[Bart B.]

Originally Posted by std7mag

I find it odd that the barrel has Winchester stamped on it, but not the original chambering.

Thousands of factory barrel chambers have been reamed out for larger cases for the same caliber. Many had the new cartridge stamped on the barrel and the original marked out.

[Listener]

Sorry for the pause, I took a few mental-health days in the Sierra; fantastically beautiful after our wet winter. Thanks for all the replies and suggestions. I am the second owner and don't think it has been rebarreled or rechambered. I'll pull the stock to see if there are any additional markings and take some pics and post them. I can also take some chamber measurements to see if that helps solve the mystery.

Tight groups,

John

[Scorch]

If it hasn't been rechambered, it's most likely still a 7X57, but get it checked.

[Listener]

The mystery deepens. I field stripped this Model 70 and pulled off the stock. No additional useful markings were found. However, it turns out that the stock is a custom job by Al Biesen from Spokane. I have attached three pics, the receiver, the barrel and receiver, and the bolt face. This was a 'bonus gun' that I never got around to until now that came along with a pre-'64 30'06. This is a bit ironic as I am familiar and comfortable with wildcats. I have another Model 70 of similar vintage in .240 Cobra that is the most accurate sporting rifle I have shot.

Tight groups,

John

[T. O'Heir]

"...Rather than rebarrel..." Waaay less expensive to rebarrel than it is to fiddle with the chamber. Especially as you'd be taking the barrel off to do anything to it.
"...The mystery deepens..." The mystery will go away with a chamber cast.
Lots of M70's were used as the basis of custom rifles. Know a guy who built a 1,000 yard DCRA(sort of our version of the NRA but without the clout) sniper rifle on one. The guy won regularly too.
"...odd that the barrel has Winchester..." Note the squiggly thing at the end of my question. Question mark '?'. Question is answered in Listener's first picture. It's on the receiver where it belongs. Means it's a custom built rifle on an M70 receiver.

[taylorce1]

Chamber cast, chamber cast, and chamber cast!

You have a custom rifle chambered in a wildcat cartridge by the stamp on the barrel.

[std7mag]

T.O.
When i made the Winchester observation it was due to Listener's original post.
Where in he stated that 7mm Vincents was stamped on the barrel, no other markings other than Winchester.
This was before any pictures.

And as Taylorce says.
Chamber cast....

[Listener]

I am a hobbiest machinist and relatively handy in general. Is it realistic to think that I could do a successful chamber cast?

[Jim Watson]

Yes.
Here are Brownell's instructions.
https://www.brownells.com/userdocs/learn/Inst-446.pdf

There are videos and other versions of procedure.
https://www.google.com/search?source...10.gMsUYw4o2gQ

I am not a wildcatter or gunsmith but I see in the second picture that the "Vincents" is not the same font as the "7MM". The short reinforce on the barrel looks like the Winchester Featherweight profile. Which is even more perplexing, they didn't make Featherweights in 7mm anything.

[BusGunner007]

Heed the 'Scorch' post.

[F. Guffey]

I am a hobbiest machinist and relatively handy in general. Is it realistic to think that I could do a successful chamber cast?

Yes I do believe you can be successful but in this crown you can never be all you can be. I cast chambers but my method/technique requires a little coaching.

I measure chambers with blind end micrometers, I also have used arbor presses. If a press can form a case in a die think what could/can be done with an arbor press.

F. Guffey

[Listener]

and the winner is...

wait for it...

Scorch with his 7x57 Mauser guess.

The prize? A nice IPA or the beverage of his choice.

Very excited to go shoot this. A big thank you all who contributed to this thread.

Best,

Listener

[Scorch]

Cheers!