spanish 93 rebarreling

[Gunnerboy]

i got a spanish 93 thats been bubba'd already so i was thinking of 257 roberts, but this made me think that if the 93s were chambered to 308 and did ok then would it be alright to go ahead and use 257+p in it being that there is only a 3-4000 psi differace in the two rnds, any input is appreciated other than that of another caliber suggestion.

 

[Stophel]

Granted, I'm not that familiar with the use of the caliber (other than reading nothing but praise for it for years), but is there something insufficient about it where you need a "+P" loading?

 

[Clipper]

I'd also look into Akley Improving it to reduce bolt thrust. You can still shoot factory Roberts to fireform cases.

 

[Slamfire]

The conversion of M93's and M1916's to 308 Win will cause a lot of controversy , especially from owners. This has been hashed out in these threads:

http://www.thehighroad.org/showthread.php?t=633704&highlight=spanish+mauser

http://www.thehighroad.org/showthread.php?t=632684&highlight=spanish+mauser

I would not convert this rifle to a 308 Win. That cartridge operates at higher pressures than the 7mm Mauser ammunition that these rifles originally used.

There are many other reasons, just look at the all the threads.


http://www.thehighroad.org/showpost.php?p=6707989&postcount=10

Originally Posted by Oceans

Thats funny Maj. Dad, I knew a correctional officer in the late '80s, who had one of them in what was supposed to be .308. This guy loved that rifle like it was a 1930s model 70. He talked about it constantly, shot it every time he went to the range and even bought an expensive case to haul it around in. I was always leery of a 1893 action chambered in .308. I was told that the Guardia Mauser was chambered for a very similar Spanish round, and not the NATO 7.62x51, and that this Spanish round was loaded to lower pressures. I do not know if this is true, maybe someone on the board does? I will say, that the rifle is handy, and nice looking.
Oceans - It is true, as I found out today, sadly.

I've had my 1916 Spanish Guardia Mauser from Samco for about 20 years now. Took it deer hunting every year until last year, when I heard about the same thing you did. I shot .308 rounds out of it.

Finally got the headspace checked by a gunsmith, and - well, the bolt locked EASILY on "no-go". And we're talking like butter. I snapped the firing pin and will have it hanging on the wall of my office soon.

http://www.thehighroad.org/showthread.php?t=632782

I recommend...
________________________________________
that you honorably retire the rifle.
My experience with the Spanish '93-type actions is that they are not suitable for rebarreling to any modern cartridge at all.
They are all soft (many years ago, I watched an old gunsmith squash one in simply tightening his action wrench onto it. When he noticed that the barrel shank wouldn't thread back into the action, and realized why, he simply took the receiver out of the wrench, laid it on his bench and smacked it with a big brass hammer until he could screw the barrel back in).
With pressures higher than about 40 KPSI (virtually all modern CF rifle cartridges), the locking lugs will set-back into their seats very quickly, increasing headspace until the bolt becomes hard to open and case heads separate. Several years ago, a customer (and friend) decided he'd like to make up a 7.62x39 rifle on just such a '93 Spanish action. I couldn't talk him out of it, so made and fitted a barrel for him. In shooting about 200 rounds of Wolf ammunition, it battered itself into just the state I described above.
Just my recommendation, but not based on hearsay.
PRD1 - mhb - Mike

 

[Gunnerboy]

I never said i was gonna build it into 308, im looking for 257 roberts to be the next contestant in that action.

 

[Slamfire]

Not familiar with the 257 Roberts. You want a cartridge that does not produce more than 40 K psia. At least that is my opinion for these old actions.

 

[MachIVshooter]

Not familiar with the 257 Roberts. You want a cartridge that does not produce more than 40 K psia

The Roberts is a 7x57 necked down to .257"

Standard .257 Roberts i s 45,000 PSI; Industry standard for the old 7x57 to be safely used in the M93 and variants is 46,000 PSI according to Speer #13. The Roberts +P, however, is rated to 50,000 PSI.

OP-

Your gun will be fine with the Roberts if you stick to standard pressure load data (and I'd probably stay a little under max just to be safe).

A shoot an unmodified M-93 7x57 and use mid-level loads, never had a problem.

 

[NCsmitty]

Your gun will be fine with the Roberts if you stick to standard pressure load data (and I'd probably stay a little under max just to be safe).

Good advice, stay within the design limits of the small ring action. The 257 Roberts is an ideal cartridge for the small ring Mausers.


NCsmitty