Newby question: Need help identifying the appropriate cartdridge for an old 7mm

This one looks like the Model 1936.. The forerunner of the Model 1954. This looks in great shape also. Please post a full lenth pic of both so we can see everything. Heres info on this one. Looks like yours was last year of production of this model.

https://en.wikipedia.org/wiki/Mexican_Mauser_Model_1936

Yes, it's 7x57 Mauser.

7x57mm Mauser. A fairly common round in South and Central America for much of the 20th Century. Here's a quick and fairly accurate thought. If the rifle is a military rifle that has not been 'sporterized' it is likely NOT a 7mm Remington Magnum or some such.

The 7x57mm Mauser round did differ - by nation as a rule - with different bullet weights and muzzle velocities. However, the external shape of the round (noting normal differences in bullet shapes) is the same and all those rifles typically used the same Mauser 1891 (pre '98 action). So a round from Columbia will chamber and fire without problem in a Chilean Mauser, but the military sight adjustments may be different.

Cartridge appears to be made in 1933. More that likely corrosive, personally I would NOT fire it, because of it's age. You have no idea how it's history. Buy a box of new shells.

Good luck

Jerry

Ammo is German manufacture: Deutsche Waffen und Munitionsfabriken. Again, looks like a date stamp rather than cartridge designator.

I don't know if I'd fire it or not. If the cases look to be in good shape, I might pull a bullet to see if there is any visible or olfactory evidence of powder degradation. Here's a good summary of what to look for. It relates to stored powder, but would apply to powder in a cartridge, too.

You can tell if a can of powder is good or bad by giving its contents a sniff test. If the smell ranges from no detectable odor to resembling alcohol, ether or acetone (from its solvent content), it is okay. If you get a terribly unpleasant, acidic odor that fries your nasal passages, extreme deterioration has taken place. The odor is difficult to describe, but my nose says the experience is quite a bit like taking a strong whiff of the fumes produced by muriatic acid.

Any change — regardless of whether it is physical, chemical or otherwise — indicates time for disposal. If a brown or rust-colored fume escapes from the container when you open it, the powder is unsuitable for use. The plastic cap on one of the containers of powder that went bad on me was originally blue in color, and the chemical changes that took place inside had actually bleached it snow white. Sudden rusting of the metal cap of a container is also a sure sign of bad things going on inside.

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Source: https://www.rifleshootermag.com/editorial/how-to-determine-gunpowder-shelf-life/83922

If all looked/smelled good, I'd probably try a round or two at least.

Charly2020! said:

Caliber: 7mm
Date: 1947
Brand: Fabrica Nacional de Armas de Mexico

I am confident this is a 7x57 Mauser as I’ve tried several 7mm variants and all are too big for this one.

Additional note: I have several boxes of ammo labeled DMW on the top and on the lower part of the rim 19 K 33. Thank you for your kind help. See pics below:

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Jackpot brother! The classic M1936 Mexican Mauser -- these were once popular for sporterizing because of their lighter small ring action. A few features like the cocking piece were borrowed from the '03 Springfield. I'd love to find one of these babies! Could you please post a photo of the entire rifle from either side, to determine whether any alterations have been made to the stock?

Since it still has the military rear sight, the barrel is also likely still in the original 7x57.

BTW, George Orwell mentioned in his Spanish Civil War account "Homage to Catalonia" that Mexican 7mm ammo was the best quality of any they were issued -- they would separate and save Mexican ammo for use in assaults.

It’s almost certainly 7x57. Put that old ammo on the shelf. Gun powder degrades unpredictably over time. New 7x57 ammo is readily available.

Lets try photos....I suck at photos on this site for some reason.
I keep forgetting at home, these are the only ones I have access to at work.

someguy2800 said:

It’s almost certainly 7x57. Put that old ammo on the shelf. Gun powder degrades unpredictably over time. New 7x57 ammo is readily available.

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Not to mention the likelihood of corrosive priming. Try pulling a bullet, dump the powder and take a look at the primer holes at the bottom of the case. If you're really lucky, these could be Boxer primed (one hole in the center) and reloadable with new primers. The headstamp described seems military so Berdan priming (a pair of small holes) is far more likely, but you never know unless you look. Don't test this with your sizing/decapping die or you can break your decapping pin.

My process with old milsurp ammo gifts is to use a kinetic bullet puller (the plastic hammer kind), dump the old powder and check the priming type. The powder goes into a small pile in the back yard and disposed by setting alight. Usually just the bullets are reusable, and even then often only after a tumble clean. I check the bullets with a magnet and segregate the non-ferrous from those with steel (many ranges do not allow steel jacketed or cored bullets.) Once I had a batch of old 30-06 that was Boxer primed, so I fired the old primers with a hammer and nail before de- and re-priming with new, added new powder charges and then reseated the cleaned up old bullets.

Old Ammo, 1947. Probably not 'rare' but it is 74 years old, and they don't make any more ammo in 1947 these days. What used to was cheap shooting ammo is now less in supply than in 1967. Check around with ammo collectors.
Old powder does degrade. But that means one is more likely to have a weak load and a stuck bullet than a blown up rifle. Even considering one is better than the other, either is a pain.
Primers are no doubt corrosive; the primers themselves doesn't have a direct corrosive effect (like some kind of acid), but does leave water attractive (hygroscopic) residue. Which can be cured by cleaning the rifle barrel and making sure nothing is left in the chamber or on the bolt face, either. There are a number of commercial cleaning products suitable, but hot (somewhat) soapy water does a great job. But then dry fully and lightly oil all the wet bits. Take the stock off before adding water.

Mr. DeLaurant's comments are totally valid. I keep old powder to use as fire starter, and I've heard it can be used on flowers or vegetables growing as fertilizer. Not much good to attempt to reuse, one never knows what powder is was or loading data.

Headstamp. DMW is (was?) a respected manufacturer with a good name. The headstamp is a 'military' style and I would expect it to loaded to the 1891 Mauser which are all the South American rifles. Safe in one is safe in all. (Which does not mean there are not 'lemon' rifles.) Manufactured 1947. The box would have information about which country ordered it. The headstamp rarely does.

Archie said:

The 7x57mm Mauser round did differ - by nation as a rule - with different bullet weights and muzzle velocities. However, the external shape of the round (noting normal differences in bullet shapes) is the same and all those rifles typically used the same Mauser 1891 (pre '98 action). So a round from Columbia will chamber and fire without problem in a Chilean Mauser, but the military sight adjustments may be different.

Click to expand...

Dave DeLaurant said:

BTW, George Orwell mentioned in his Spanish Civil War account "Homage to Catalonia" that Mexican 7mm ammo was the best quality of any they were issued -- they would separate and save Mexican ammo for use in assaults.

Click to expand...

You learn something new every day on here.