spanish mauser help

[brino308]

First I have to say that this site is great,lots of info for a beginner. My most recent project is a newly acquired small ring mauser . One that was re-barreled and chambered for 7.62x51 nato and then imported by samco global. I slugged the barrel and found it to be .310 groove to groove. I would like to cast some GC boolits for it but not sure where to start. Would .312 be ok ? Any help would be greatly appreciated .

[Yodogsandman]

Slug and size to the throat diameter. Sizing this way prevents the boolit from shifting and bending while entering the bore during the phase where the boolit is released from the case neck and is otherwise unsupported when fired. That way the boolit enters the bore straight when it's smacked in the butt with all that pressure, providing better accuracy.

Sometimes you can just measure the inside of a case neck from a case fired in that rifle to get a quick idea of what you might need.

[castalott]

Welcome brino... I have a small ring Mauser in 308. I don't shoot full power loads in it as it doesn't have the third 'safety' lug. But it is a very good shooter with plain base boolets and light charges. Flat nose boolets maybe won't feed from the magazine so a pointed boolet would be called for. I suppose you know to not put a round in the chamber and close the bolt as the rim of the cartridge is designed to go behind the extractor as it is being fed. Put the round in the chamber and close the bolt and you FORCE the extractor over the rim. Not good.

I might suggest the Lee Bullets for the 7.62x39.... especially if you have a 310 or 311 sizer.

Wait for others to chime in....there will be some good ideas here...

Dale

[runfiverun]

that lee sized to 311 should do a good job.
yodog, also made a good suggestion to measure the inside of a case neck this will give you an idea if the 311 or whatever size will chamber.
I have seen some 308's that wouldn't even chamber a 311 bullet because of the chambers neck clearance.
yours will probably chamber an 8mm bullet.
but you gotta start somewhere.
you didn't mention the lands [bore] diameter if it's 300 you need a nose in that area if it's bigger then going with the bigger nose diameter is a better way to go.

[MostlyLeverGuns]

The Spanish Mausers in 7.62 x 51 are based on Spain's 7.62 x 51 CETME or Spanish cartridge. It does not meet NATO pressure standards. Spain used a lighter bullet at lower velocity in their version of the 7.62 x 51. The pressure of the CETME cartridge is substantially less the the .308 Win or 7.62 x 51. That is why the early Spanish Mauser could be converted without incident. Be cautious and conservative with the Spanish Mausers in 7.62. Spain did finally move to the 7.62 NATO but the Spanish Mausers were the CETME version.

[brino308]

Thanks ,I knew I came to the right place,will be ordering that 7.62x39 mold this weekend . Haven't measured case mouth yet but will shoot a couple factory loads and check that as well.

[castalott]

I really would not shoot 308 factory loads in that gun. The original loading was 7mm mauser and it is not loaded that hot. I probably would not shoot 7.62 ball in it either...But that's just me...

[HangFireW8]

Another mold you should look at is the Lee C312 185gr round nose. I have a .310" bore FN Mauser and it simply loves this boolit. Size to .310 or .311 and have at it. You only need worry about the throat diameter if that doesn't work, but it usually does.

I have small ring Mausers including one I use regularly, one of the great things about Cast is you don't have to worry about what factory ammo will do to your rifle. Shooting cast around 1500-2000 fps it will probably last forever, it hardly warms up during long strings of firing.

[brino308]

Thanks for the info, should be fun developing a pet load for this old rifle