M70 Magnum bolt faces

[Ray B]

 

[Ray B]

Above are four bolt faces of some Magnum M70s spanning several years of production. Left to Right: 1996 .458; 1953 404; 1991 375 RUM; 1937 375 H&H
The reason for the comparison was to determine if the extractor for the 375 H&H had been altered. It appears that maybe it was, since it seems to have less shoulder and more taper than the other 3; but it is considerably older than the others so it may have been slightly different specifications from the factory. The interesting aspect of the rifles is that while the depth of the magazines are all constant at 47mm the first three hold 3 cartridges with space to insert a fourth enough that the bolt can slide over it sufficient to chamber it, giving the first three rifles a capacity of four while the older 375magazine can hold 4 cartridges with space to hold a fifth so that it can be chambered, giving the rifle a 5 shot capacity. The rails don't appear to be altered so the only conclusion that I can make is that the H&H cartridges are allowed to spread a little wider (horizontally) in the magazine to allow for the extra vertical space. Anyone having information on this, please chime in.

 

[Hoss Delgado]

My pre war model in .375 originally was owned by by Great Granddad who bought it in '38 or '39. He passed it on to my Granddad who gifted it to me . Mine holds 4 rounds in the magazine just like yours does. But unlike yours , mine can't be topped off with a fifth round. When l showed it to a gunsmith , he said that the only way a fifth round can be topped off in the chamber is if a gunsmith opened up the extractors. Very interesting question actually.

 

[Opposite Pole]

Mine is a 2014 vintage .416 Rem Mag. 3+1 capacity (user manual confirms this).

According to my manual the capacity of standard M70 is 4+1, while magnum and WSM are 3+1. The manual states that in order to load the rfile to full capacity one should load the magazine and place a round directly in the chamber and close the bolt while holding down the rounds in the mag. It states that more resistance will be felt on closing the bolt as the extractor has to jump over the rim.

http://www.winchesterguns.com/content/dam/winchester-repeating-arms/support/owners-manuals/2019/17-WRA-424_Model 70_SR_OM_WEB.pdf

 

[Ray B]

That Norma ammunition made quite the impression on the boltface.

 

[Opposite Pole]

That Norma ammunition made quite the impression on the boltface.

Sure looks like that. I bought the rifle new and only shot factory Hornady rounds through it so far. There’s an archaic law in Poland that any new gun sold by a shop needs to be fired 3 times and shells be sent to the police so the imprint on the bolt is from these rounds. What you’re seeing though is not an imprint but rather lack of it. Some Norma cases have markings on the rim carved quite deep (I’ve got a batch of 9.3x74R like that) and if you fire them on a clean bolt face such as in brand new gun without brass deposits on the face yet it looks like an imprint but it’s actually lack of brass deposits where markings were cut in the rim.

 

[Nkawu]

My M70 standard holds 5 down + 1. It’s a Classic stainless 30-06 with wooden stock (lefty). The mag looks magnum length with a small spacer at the rear. I’m not sure if the ejection port would allow a loaded mag round to exit? Are the ejection ports different for standard and magnum?

 

[Curious]

My M70 standard holds 5 down + 1. It’s a Classic stainless 30-06 with wooden stock (lefty). The mag looks magnum length with a small spacer at the rear. I’m not sure if the ejection port would allow a loaded mag round to exit? Are the ejection ports different for standard and magnum?

My M70 SG .30-06, built circa 2012, allows extraction and ejection of a loaded round. This is a safety issue, so I'm going to guess that yours allows extraction as well.

 

[Forrest Halley]

I'm topping off my 70 by loading one in the mag and chambering it. Then I safe the rifle and flip it over and dump three shells into the magazine and shut the floorplate. It closes easily so, am I doing something wrong? I learned this trick with my other 70 in .223. Seems like a fast way to reload too.

 

[Ray B]

About the only detail with loading from the bottom is to know which side of the stack the last shell in will go so that it aligns with the follower.

 

[Forrest Halley]

About the only detail with loading from the bottom is to know which side of the stack the last shell in will go so that it aligns with the follower.

This is a frivolous effort. Throw them in, tilt the muzzle up, and watch them sort themselves out as the follower comes under spring tension. Similar to aligning the revolver cylinder into the cylinder stop notch when speed reloading. A detail oriented effort that is unnecessary in the interest of reliability or haste.

 

[tunatoy76]

This is a frivolous effort. Throw them in, tilt the muzzle up, and watch them sort themselves out as the follower comes under spring tension. Similar to aligning the revolver cylinder into the cylinder stop notch when speed reloading. A detail oriented effort that is unnecessary in the interest of reliability or haste.

Until you try doing it while walking backwards through scrub with a pissed off Beasty eyeballing you

 

[Ray B]

This is a frivolous effort. Throw them in, tilt the muzzle up, and watch them sort themselves out as the follower comes under spring tension. Similar to aligning the revolver cylinder into the cylinder stop notch when speed reloading. A detail oriented effort that is unnecessary in the interest of reliability or haste.

Not quite certain that I believe you. It seems to me that if the cartridges were started in on the wrong side that when the floorplate was closed and the follower pushed against the stack, that the follower will possibly push the bottom cartridge over so that it dropped into the follower but the other cartridges are not likely to change sides, making for a problem. Maybe that's why I prefer to load from the top so that all cartridges are properly placed. Maybe I'm just being Obsessive.

 

[Wyatt Smith]

If you can press the cartridge intended for the chamber into the magazine just a little you can slip it under the extractor I do this with my m70 375. There is another thread on here where I learned that trick. Just press it down and push the bolt forward and the rim should be below the extractor, the let it up under the extractor.

 

[Forrest Halley]

So there is no mechanical infeasibility.

I had the single load figured out, but thank you for bringing it up @Wyatt Smith . Potentially saved my extractor and I appreciate it.

 

[Forrest Halley]

@Ray B , I have revisited the issue in practice and it turns out your thoughts have extraordinary merit. I was getting away with this dumpster loading with the 300 grain RNSP. The 300 grain Sierra's are a bit of a more finicky story on loading and can sometimes cause a condition where the cartridge is aligned nose up instead of level. It corrects with a cycling of the bolt, however I am not happy with a failed feed. Do you have any thoughts about polishing the magazine follower of feed ramps? The follower is apparently bead blasted and the ramps have machine marks.