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View Full Version : Low pressure .308 and the 1916 Mauser


BlueTrain
July 19, 2007, 12:02 PM
I've been looking at a very nicely refinished Model 1916 Spanish Civil Guard rifle. It's even in .308 Nato, originally in 7mm Mauser. It has a straight stock and a bent bolt handle. It is supposedly the 1893 Mauser.

The real problem is that the pre-98 Mausers cannot handle the .308 pressure, at least safely for very long. In fact, postings on various message boards suggest it is an unsafe conversion, briefly stated. There have been suggestions to use a chamber insert and use 7.62x39, which sounds OK but I've never seen such a thing, nor one advertised.

Now comes Federal with a low-pressure load supposedly intended for just such a thing, a military surplus rifle. They achieve the goal with a lighter bullet and less propellant and the result is something close to a .30-30. On the surface it sounds like a good idea if you really wanted something like I've been looking at. It goes without saying that if you have to use special select ammuntition, it virtually negates having it in .308 or more accurately, 7.62mm NATO, in the first place. Still, with what little shooting I do, it makes little difference.

Does anyone here actually use such a combination or this particular load for their own .308 rifle? I believe Federal calls the round the Power Shock. And does anyone have a converted Model 1916 Civil Guard short rifle?

JR47
July 19, 2007, 12:45 PM
7x57 SAAMI specs are 51,000 PSI, while .308 specs are 62,000 PSI.

However, the specs on saboted loads in .308 are 52,000 PSI.

I didn't see a Federal Load listed as reduced velocity. However, Remington has a Managed Recoil Load in .308, with a 125 gr. bullet, at a little under 2700 fps. They have no SAAMI specs listed in their site, though.

I have a Model 1916 Spanish Mauser, converted to 7.62x51. I have fired several hundred NATO spec loads through it with no change in headspace. I believe that NATO pressure loadings are actually less than SAAMI for the 7.62 chambering.

moose fat
July 19, 2007, 12:59 PM
:) Do a thread search on 7.62 vs. 308.

This was discused, and will be discused more, when the surplus Ishapore 2a(s) came out. Rem Managed recoil works good according to other posts.

BlueTrain
July 19, 2007, 03:24 PM
My inquiry wasn't about the .308 Winchester compared with the 7.62 NATO. However, as it turns out, there is absolutely no reference on the Federal website about a low recoil .308, which one article referred to as the 308LR1 load. They did mention low recoil but I couldn't find a cartridge so described.
The original article mentioned a 170 gr bullet but there is no such Federal .308 load.

Remington has low recoil loads they called managed recoil and in the case of the .308, uses a 125 gr bullet. None of the various ammuntion company websites mention pressure and I did no research beyond that. I believe pressure figures are given in the Barnes book, at least for some cartridges, but the low pressure loads are probably too new.

44 AMP
July 19, 2007, 05:32 PM
Handload!

Abndoc
July 19, 2007, 05:57 PM
It's funny that this thread should come up right now. I was just leaving for the range and am just waiting for my brother to show up. And I'm taking my 1916 Spanish Mauser in .308.

I shoot 47grains of H4350 with a muzzle velocity of about 2500fps with a 150 grain fmj. This gives me, by the book, 37,500cup of pressure. This is well below the mid to upper 40's that the 7X57 is rated for.

I figure, why beat up an old horse. It shoots well with this load and if I want to shoot something with more oomph, I'll get something else out of the safe.

I'm not familiar with the reduced recoil loads, but I would check pressures before I used it. For me, this rifle is strictly a handloading proposition.

Scorch
July 19, 2007, 07:27 PM
I used to have a Spanish mauser in 7X57, and I shot some pretty stout military loads in it. Operating pressure of the 7X57 is 52,000 cup, IIRC. Operating pressure of 7.62X51 is 48,000 cup, IIRC, so it should be fine with military equivalent loads. Just use FMJ WW white box or Federal FMJ ammo in it and you should be fine. If you reload for it, use the data for 7.62X51 service rifle loads.

BlueTrain
July 20, 2007, 06:39 AM
This is a little surprising. Some sources state that the average operating pressure of 7x57 Mauser is some less than 45,000 (apparently greater than .30-40 Krag/.30 Government). The SAAMI website does not have this information, though it is available for sale. There are pressure tables published on Handloads.com and Leverguns.com. Mostly the two tables agree but some numbers are a little suspect and neither list is exhaustive.

The table on Handloads.com gives 35,000 for 8mm Mauser, which seems mighty low when .303 British is given as 49,000 and .30-30 Winchester at 42,000. In any case, the table on Leverguns.com states the pressure specifications are Maximum Average pressure (Piezo measurement method).

The .308 Winchester is listed as 62,000 and that is way above what I would call a comfortable safety margin for my purposes. I might note in passing that the differences in the standard and +P handgun ammunition (for .38 Special, 9mm and .45 ACP) is actually quite small, something like 10% higher but the two tables are not in agreement on each item. Overall the tables are pretty interesting.

Lastly, neither table distinguishes the .308 Winchester from 7.62 NATO, nor does the SAAMI website in its list of unsafe combinations, which does say not to use 9mm NATO in a 9mm Parabellum handgun!

Abndoc
July 20, 2007, 07:47 AM
Well, it didn't blow up.

52,000 cup seems a tad high. I lean toward the more conservative load figures with a rifle this old.

I had some surplus 7.62 NATO and I did put about 40 round through this rifle with no ill effects, but I'm unsure what a steady diet of this would do. I unloaded the rest and reloaded them to a lower pressure.

JR47
July 20, 2007, 10:09 AM
Here's a list, dated 2004.

http://www.leverguns.com/articles/saami_pressures.htm