So I picked up this Mauser

[Gene L]

Hmmmm. . .

Is there any sign of there having been a rear sight mounted on the barrel? By the engraving it was pretty clearly intended to not have a receiver sight on it. . .and it's an American-made (Lyman) receiver sight anyway.

Could probably tell some really good stories.

I've got a guild rifle in 7 x 57 mm J (not JS) made before WW 1 that has a Lyman sight on it, which is original. I had it researched from the German Gun Collector's site. It's got lots of marking on it, including the stocker # and where it was sold. The action isn't from a military rifle it's directly from the Mauser company, pre WW 1.

I'll never sale it because no one will give me what it's worth.

Also, it's got a claw scope-sight mount on it.

[JunkCollector]

It's been awhile since I've been this curious about someone else's mystery gun...

I like mysteries too.
Been racking my brain a big part of the day knowing I had o6 rounds somewhere to try....the where the F would I have put them.
Out to dinner oh yeah there.....mystery solved.

Tried and the chamber mystery remains.
Maybe a simple 308

[Wambli Ska]

Or 7.65 Mauser

[JunkCollector]

Or 7.65 Mauser

Not exactly funny.......but could very well be 8

[Wambli Ska]

Both the 7.65 and 8mm Mauser are very good rounds! Definitely hand load propositions but it’d be a hoot to take one of those monster bucks you get in your neck of the woods, or even better, a bear! with an old European round chambered “Stalking Rifle”!

[Gene L]

Correction to my last post...my rifle is in 7.9 x 57, or 8mm. NOT 7mm Mausser. I wish it were.

Note: any military round is going to be a good hunting round. There was a lot of research going in to adopting them to the armed forces that led to their adoption.

[JunkCollector]

My best guess as of right now is going to be 303 British.
The bore did seem a bit over 308.
I had these 32 hollow base wadcutters so tapped one down tapped it back out and came up with 311 groove diameter.

Not quite sure what the future will hold for this one.
I initially want to have the stock and screws attended to.
The clambering need to find if I'm correct
Then decide if I want to stay with that or ?
I do have a bunch of 257 roberts brass around

Always thought 6.5 ×55 was neat too.

[CPJ 2.0]

I don’t know what it is, but I’ve got $5 that says it ain’t .303 Limey

[Wambli Ska]

My best guess as of right now is going to be 303 British.
The bore did seem a bit over 308.
I had these 32 hollow base wadcutters so tapped one down tapped it back out and came up with 311 groove diameter.

Not quite sure what the future will hold for this one.
I initially want to have the stock and screws attended to.
The clambering need to find if I'm correct
Then decide if I want to stay with that or ?
I do have a bunch of 257 roberts brass around

Always thought 6.5 ×55 was neat too.

Measure the lands. The groove diameter for the 7.65×53mm Argentine Mauser (often referred to as 7.65 Mauser) is typically .312 to .313 inches (approx. 7.92–7.95 mm). While the land diameter (bore) is 7.65 mm (0.301"), the proper bullet diameter for this rifle, which corresponds to the groove-to-groove measurement, is (0.313"). 

If it chambers a 30-06 it was one of the THOUSANDS of Argentinian Mausers that were imported into the USA and rechambered to 30-06 thinking the bore was "close enough", and it is. Many folks have been shooting 30-06 on these guns for almost 100 years and getting decent "hunting accuracy" as defined in the early part of the 20th century. If a 30-06 does not chamber but a 7mm Mauser does, or a 257 Roberts, you are in luck. There is properly head stamped 7.65 Mauser ammo out there and it's a very nice round! Remington even used to load it as part of their CoreLoct line, don't think they still do. I used to have an Argentine Mauser and if this turns out to be the case for you I'll see if I still have ammo for it and send it to you.

If it is chambered for 30-06 you could use 30-06 dies but get a 7.65 expander and a 7.65 seater/crimper and with hybrid dies you'll have a hell of a shooter. I guess you could call it 7.65-06.

[JunkCollector]

It's definitely a german 98 mauser
Receiver has the eagle
Pretty sure the crown over B means for the commercial market.
Unless your only talking about the barrel ?

[Wambli Ska]

Argentinian Mausers were made in Germany for the Argentinian Military. Most of them were exported into the US as surplus when their ARMY moved to more modern platforms and many companies and individuals made sporters out of them. Untouched Argentine and Chilean Mausers (also chambered in 7.65) bring big money because they are scarce.

The barrel probably has no markings because it was turned down to get rid of the steps in the military profile,

[Freezer]

Let me go Baba with this one. Will it chamber a piece of 06 brass? If not will it chamber 308 Brass? Just find out what it will chamber, add 5 grains of pistol powder and a primer, fill the brass with corn meal and cap it with wax. Fire formed brass, mystery solved. I used to fire form 7 TCU brass from 223 the same way.

I bought a beautiful sporterized 6.5 Arisaka with a Mannlicher birds eye maple stock. Thinking it was a 6.5 Jap I bought dies and bullets. The first shot surprised me, no recoil. Without thinking I ejected the brass without inspection and chambered another round. NO Hole on the paper. I ejected the brass and found there was no shoulder. Someone had rechambered it to 6.5-257 Roberts. It was a common conversion in the day. I spent $100 on new dies, reloaded some ammo and found it printed a 6" group at 25 yards. I gave the rifle to my brother, he had an ER Shaw barrel installed and it's now a 260 Remington.

My guess is you have a 7.65 Arg or a 7.65-06. Either way it will be interesting and .311 bullets are available.

[JunkCollector]

Won't chamber 06 brass
Tried 243 and no there too
Will try a roberts tomorrow

[Wambli Ska]

True process of elimination. There you go

[JunkCollector]

Roberts close to being able to close bolt but still no

[Freezer]

Base to bevel to neck All are 20*
243 1.634 to 1.804
308 1.556 to 1.712 ***
7.65 1.756 to 1.858
257 1.728 to 1.912

This is intriguing!

[Wambli Ska]

Roberts close to being able to close bolt but still no

That makes sense since I believe the 257 Robert’s is slightly wider at the base of the shoulder than the 7.65

[JunkCollector]

The shoulder does seem to be the hangup

[Jay]

Chamber casting alloy is $14. And reusable…

https://www.brownells.com/tools-cleanin ... =080027050

[JunkCollector]

It's been ordered.
Just playing around in the meantime

[Freezer]

OH! Now you'e making us wait to find out

[Jayhawker]

Holy crap! That's one of those guns that would be impossible to pass up...Lovely bit of work...

[JunkCollector]

OH! Now you'e making us wait to find out

Not necessarily
I can grab an Argentine round.
I know where some live...lol

[JunkCollector]

Holy crap! That's one of those guns that would be impossible to pass up...Lovely bit of work...

Thanks Sir it was
Knew it would take some work but will be worth it.

[Varmintmist]

Possible 8x57J with a .318 bore if its old enough. 8x57JS were .323. Dont mix and match.