Reloading for 7mm Mauser

[amadeus76]

Recently acquired a Chilean 1912 Steyr Mauser in 7mm and am looking for a starting point for reloads. I can find some decent soft tip hunting rounds and I'm certainly looking to find a good recipe for that, but I'm also interested in pure accuracy load using match grade bullets for vintage competition...

Anyone reload for this round?

Information

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[Parashooter]

. . . Anyone reload for this round?

Yes, many folks reload 7x57. It's one of the best.

Lots of data at Take Aim at Rifle Reloading Data | Hodgdon Reloading and elsewhere online. Chilean M1912 in sound condition can handle anything published by established component or tool manufacturers.

[Brian Dick]

I deer hunt with a 1990 vintage Winchester Model 70 Featherweight in 7x57 and wouldn't trade it for the world.

[Bruce McAskill]

That is the same rifle and cartridge I use for hunting too. I have always enjoyed my M70 Featherweight in 7x57. 44 gr of 4320 with a 140 class bullet means venison on the table.

[amadeus76]

Side question... Does anyone know what bullet weight the 1912 Mauser is graduated for?

[Ovidio]

I use 41 grs. of N150 behind a 140 grs. FMJBT from S&B
OAL 78 mm.
WLR primer.
Works fine.

[Doco overboard]

I use 45g of H4350 and a 140 bt bullet, WLR primer. Shot right through a small sapling one time that I didn't see on a drive and still flattened a decent buck.

[Sunray]

"...what bullet weight..." Don't like quoting Wikipedia, but they claim: "The rear tangent sight was graduated for 1893 pattern 7×57mm Mauser cartridges loaded with a 11.2-gram (172.8 gr) long round-nosed bullet from 400 to 2,000 m (437 to 2,187 yd) in 100 m (109 yd) increments."
Prvi loads a 173 grain SP. I'd be loading or using a 139/140 though. Just for the lighter felt recoil.

[amadeus76]

"...what bullet weight..." Don't like quoting Wikipedia, but they claim: "The rear tangent sight was graduated for 1893 pattern 7×57mm Mauser cartridges loaded with a 11.2-gram (172.8 gr) long round-nosed bullet from 400 to 2,000 m (437 to 2,187 yd) in 100 m (109 yd) increments."
Prvi loads a 173 grain SP. I'd be loading or using a 139/140 though. Just for the lighter felt recoil.

I saw that, but further down is says...

"...[In 1913] the Spanish ordnance authorities issued a redesigned 7×57mm cartridge with a spitzer bullet...loaded with a 9-gram (138.9 gr) spitzer bullet..."

And then again, farther down...

"After that military ball ammunition loaded with a 10.5-gram (162.0 gr) spitzer bullet..."

The problem is the page is referring to the Spanish 1893 Mauser and not the 1912 Steyr Mauser which is a Mauser 98 action. I can't find anything anywhere specifically talking about the Chilean 1912 Mauser.

[Parashooter]

Originally Posted by amadeus76
Side question... Does anyone know what bullet weight the 1912 Mauser is graduated for?

Interesting question. I have a box of Chilean military 7x57 dated 1976. It is loaded with a 138-grain FMJ spitzer bullet. This is a clue but the real answer involves some math.

On my M1912 Chilean, the rear sighting surface moves vertically .26" when raised from 300 to 1000 (meters). Given the rifle's 25.6" sight radius, this corresponds to a difference of 34.91 minutes of angle - reasonably close to the calculated "come-up" from 300 to 1000 meters with a projectile having a BC of .425 at 870 m/s muzzle velocity (2854 fps). This velocity is entirely within the practical span of acceptable-pressure loads from the 29" barrel of the M1912.

By contrast, the old 170-grain RN bullet at a practical 750 m/s (2460 fps) would need a come-up of almost 70 MOA from 300 to 1000 meters. It therefore seems reasonable to assume that my M1912 is sighted for a faster spitzer much like my Chilean military sample.