A few Mauser Questions

[Guns&Religion]

I went to the range over the weekend with a good friend of mine. He brought his rifle, which was given to him by his father in law. It's a .308, but he knows little else about it. He was having trouble hitting the target with it, so I asked him if it was ok if I examined it. (I also got permission from him to post these pics to find out about it.)

The markings say it's a "Mauser Modelo Argentine 1891" There's also a mark on the top of the chamber that says "308 Cal" so I think it was rechambered. I was just wondering, would the barrel have to be changed to rechamber this rifle? (It was probably chambered in 7.65 Argentine, which has a bullet diameter of .311 thousands of an inch, and it's currently 308, which has a diameter of .308 thousands of an inch. Can anyone tell from these pics if the barrel has been changed and would it be necessary for a conversion from 7.65 Argentine to .308 Win?

My friend had trouble shooting it accurately, but I checked the rifling and it looks really good. I'm just wondering, Is the problem the rifle, or my friend having a bad day at the range?

 

[Uncle Grinch]

Think you are on the right track. Most likely it was rechambered, so you now have a 308 that needs .311 bullets. Think 303 British, 7.7 Jap or 7.65 Arg. Typically accuracy will suffer using undersize bullets.

As this is a '91 Argentine action, I would suggest handloading to a lower pressure level and would even consider using cast bullets that fit the groove better, i.e., .311~.314. You will find you'll get much better accuracy, albeit, with lower velocity, from 1200 to 1800 fps being optimum for cast.

The barrel appears to be original with the rear sight sleeve removed and the front sight replaced. It may have even been shortened.

The '91 Argentine is a sweet rifle, especially the way your friends is set up. I'd be prudent and not shoot factory 308 ammo unless it's loaded down.

 

[Guns&Religion]

Thank you for the input. I didn't actually shoot the rifle, but I noticed that I was getting much better accuraccy than my friend was, and I was shooting a Norinco SKS

I knew there had to be some problem affecting his Mauser, even though it's in beautiful condition.

 

[dfariswheel]

It was a common practice for importers to re-chamber the Model 1909 Argentine rifle, and somewhat less common to re-chamber the Model 1891 Argentine rifles.
The Model 1909 was a large ring action that could handle the 30-06 so they were usually re-chambered for the 30-06 since the Argentine 7.65 cartridge is more or less just a very slightly shorter 30-06.

It was less common to re-chamber the Model 1891 to .308.
In order to re-chamber to the .308. the barrel had to be set back in order to allow re-chambering for the shorter .308 round.

As above, the 7.65 bullet is larger then the .308 so accuracy is usually less then great.
Also, due to the small ring 1891 action which is not as strong as later actions, I'd load lighter loads for it.

 

[lefteyedom]

Rebarrel the rifle to 7X57 or 8x57would be my suggestion.
But I am president of the $100 saddle on a $5 mule club

 

[murdoc rose]

yep as we have figured out that is a chopped 91 Argentine. I would vote a rebarrel. How does the crown look? Do you see any import marks on it?

Personally I wouldn't fire the gun or recommend doing so. These guns and other like them where commonly rechambered/rebarreled.

 

[Guns&Religion]

Thanks for the response guys.

The crown looked like it was in good shape to me, just like the rifling and the overall condition of the rest of the rifle.

If a rebarrel is necessary, though, it sounds like we are approaching the cost purchasing another good but used rifle.

 

[StrawHat]

An easy way to check if the bore is .311 or .308 is to see if a .308 bullet will slide down the bore. If it is a very tight fit, you have a .308 bore. If it drops through, larger than ,308.

If you handload, there are plenty of molds available to cast bullets of the correct diameter.

 

[Sam1911]

We had a thread here a few weeks ago where a guy wanted to have his barrel re-lined because it was "shot out." Turns out it was simply an older version with a larger bore than modern guns and needed the old style larger bullets. He got the right bullets, his accuracy improved, and he's a happy guy with his guns still in original condition.

That's exactly how I'd approach this. Load a cast bullet of the correct diameter (these are NOT hard to find) and I bet the accuracy will be quite a pleasant surprise.

He'll have a soft-shooting and accurate rifle, quite capable of taking 'most any game he's likely to hunt.

 

[Scimmia]

An easy way to check if the bore is .311 or .308 is to see if a .308 bullet will slide down the bore. If it is a very tight fit, you have a .308 bore. If it drops through, larger than ,308.

If you handload, there are plenty of molds available to cast bullets of the correct diameter.

Not a good check at all. When we're talking .308 or .311 we're talking about groove diameter. The bore (land) diameter of the 7.65 Argentine Mauser is going to be around .300-.303 which a .308 bullet will not drop through.

 

[Sam1911]

Right. You really have to do a slug test (drive a soft lead slug like a fishing weight through the bore) to determine the groove diameter accurately.

 

[fguffey]

7.65mm53 Belgium Mauser to 308W, the 308W reamer will not clear up the 7.65mm53 chamber, the chamber from the bolt face to the shoulder of the chamber of the 7.65mm53 chamber is .196'” longer than the 308W chamber. The chamber length of the 7.65mm53 BM is longer than the 308W chamber by .095”.

I would check the barrel channel for evidence the barrel was moved back, I do not see an up side but when using 308 W 30 caliber bullets pressure is reduced because of the loose fit between the bullet and barrel diameter. If .311” bullets are used pressure will increase.

Then there are the conversions, 7mm57 barrels were inserted then converted to 308W, then there is a chance a 308W barrel was used with a with a small diameter shank, again, I do not see an upside.

http://dutchman.rebooty.com/1895Chile.html

Check the rifle for gas escape and a means of holding the bolt if the front lugs fail. One South American rifle before the Model 98 has a ‘form’ of a third lug.

F. Guffey

 

[StrawHat]

My mistake. Not enough coffee when I posted the erroneous statement.