Chambering a .30 Cal. blank into 7.65 Argentine Mauser

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elpocho

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Hi gentlemen,

Here is my predicament. I have a heavy barrel blank with a .30 Cal. bore and I would like to chamber it for the 7.65 Argentine Mauser. Obviously I will have to hand load using bullet in .308 diameter. but I would like to know if this is possible and who could perform this type of work in Ontario.

The blank is already threaded and has a very short chamber already cut into it, the muzzle needs to be cut and crowned and then mounted into a 1935 Mauser action.

Any feedback will be greatly appreciated.
 
You are going to need a reamer with an appropriately ground pilot. You will also need a loading die set up for .308" bullets.
There are a number of 'smiths who could do the work.
This is not going to be a low cost project, but it would certainly be possible.
 
tiriaq said:
You are going to need a reamer with an appropriately ground pilot. You will also need a loading die set up for .308" bullets.
There are a number of 'smiths who could do the work.
This is not going to be a low cost project, but it would certainly be possible.
Click to expand...

Thanks for your prompt reply.

Regarding the loading die I was thinking of using a regular full length or half length die, whatever I can get my hands on and then use a .308 neck sizing die. This should do the trick without having to order special expensive dies.

Can you suggest a smith that could do this work?

Thanks
 
You could probably get a Lee collet necksizing die with an appropriately sized mandrel.
If a reamer is going to be specially ordered, it might be an idea to have the neck ground for use with .30 bullets, as well as the pilot being appropriately sized. If the chamber is cut with a neck of standard diameter, it is really on the loose side for ammunition loaded with a .308 bullet. Of course, standard 7.65 ammunition could not be used.
You could ask Jason at Gunco, Doug at Epps. There are others.
I know of a rifle that was made in .30/.303. This is not much different from what you want to do. I do think that there is going to be a bit of a sticker shock, when you get a quote for the job.
I would be really tempted to see if the action would feed .308, as is, and if there is no problem, go with that cartridge.
 
"...blank is already threaded..." For a 1909 Argentine Mauser? Your rifle might have been made in 1935, but it's a 1909.
The 7.65 Argentine Mauser doesn't use .308" bullets. Uses .311" bullets. Case mouth diameter is .338". The Argentine sizing die won't size to use a .308" bullet. A .308 die won't size the case body to be anything like the 7.65 Argentine. Cu$tom made die$.
7.65 Argentine brass isn't exactly cheap anyway. Can be made out of .30-06, .270 Winchester, 7mm Mauser, and 8mm Mauser brass, though.
"...if the action would feed .308..." Loaded cartridge is 170 thou shorter. Empty case is only 5 thou longer. Don't have pressure figures for the Argentine, but I suspect it'd be lower than the .308. The rifle may not handle .308 pressures.
 
tiriaq said:
You could probably get a Lee collet necksizing die with an appropriately sized mandrel.
If a reamer is going to be specially ordered, it might be an idea to have the neck ground for use with .30 bullets, as well as the pilot being appropriately sized. If the chamber is cut with a neck of standard diameter, it is really on the loose side for ammunition loaded with a .308 bullet. Of course, standard 7.65 ammunition could not be used.
You could ask Jason at Gunco, Doug at Epps. There are others.
I know of a rifle that was made in .30/.303. This is not much different from what you want to do. I do think that there is going to be a bit of a sticker shock, when you get a quote for the job.
I would be really tempted to see if the action would feed .308, as is, and if there is no problem, go with that cartridge.
Click to expand...

Thanks for the info, I will contact Gunco and Epps and see what happens. And yes, I know that it will not be cheap but this is a nice blank and would like to make someting more unique than a .308. I can always go and buy one for a less cash but I already have one. Not that the 7.65x53 is any better than the .308 but it will give something different to reload.

sunray said:
"...blank is already threaded..." For a 1909 Argentine Mauser? Your rifle might have been made in 1935, but it's a 1909.
The 7.65 Argentine Mauser doesn't use .308" bullets. Uses .311" bullets. Case mouth diameter is .338". The Argentine sizing die won't size to use a .308" bullet. A .308 die won't size the case body to be anything like the 7.65 Argentine. Cu$tom made die$.
7.65 Argentine brass isn't exactly cheap anyway. Can be made out of .30-06, .270 Winchester, 7mm Mauser, and 8mm Mauser brass, though.
"...if the action would feed .308..." Loaded cartridge is 170 thou shorter. Empty case is only 5 thou longer. Don't have pressure figures for the Argentine, but I suspect it'd be lower than the .308. The rifle may not handle .308 pressures.
Click to expand...

sunray, the blank is already threaded but not for a 1909 Mauser, I got the blank and the action at different places although the blank might have been made for an FN FAL in Argentina because I got it there. If this is the case it would have been hammer forged and it should be .308 in diameter. However, I will have the barrel slugged just in case. If you happen to be right, that will save me a few pe$o$.

Regarding the dies, It should not be a problem, as mentioned before, I will use regular 7.65 dies and use a neck sizing die or a Lee collet die as tiriaq suggested.

As for the pressures, I already have a 1909 that had a new Israeli Mouser 7.62x51 (.308 Winchester) barrel installed. I did this because the original 7.65 Argentine barrel was pitted so badly that it looked like a smoothbore. Now it shoots like a charm and is very accurate. If I'm not mistaken the 1909 actions were pressure tested at 100.000 Psi. I'm not so sure about the 1935 actions made in Argentina under license but for what I have read, they should be strong enough to put up with any cartridge in the 50.000 to 60.000 Psi.

Nevertheless, if all of this ends up being a lemon I can always choose a more popular cartridge in either.308" or 7.62mm. but will try to see this to the end.
 
"...threaded but not for a 1909 Mauser..." How long is the barrel? If it's long enough, you could have the smithy cut the threads and partial chamber off and start from scratch. The threads will require changing anyway.
"...FN FAL..." If it's a heavy barrel it was likely made for an MG. Threaded but only partially chambered means it never got put on anything. Most likely means it's unfired. This is good. Very good.
Israeli Mausers were made by FN. If that barrel didn't need re-threading, you're ahead of the game.
"...in either .308" or 7.62mm..." Same thing. Sort of. .308", mathmatically, converts to 7.82mm. 7.62mm is the bore diameter. .308 is the diameter groove to groove. I'd forget about the 7.65 though. Too many expensive things needed to make it work. Any .30 calibre based on the .308 case will do. The 7.65 has the same case head diameter of .473". Gives you a lot of options.
 
"...a .308 expander in the 7.65 die..." A .308 expander will go into a 7.65 case without touching the case. The 7.65 is bigger than .308". It uses a .311" bullet.
 
sunray said:
"...a .308 expander in the 7.65 die..." A .308 expander will go into a 7.65 case without touching the case. The 7.65 is bigger than .308". It uses a .311" bullet.
Click to expand...

Whether this would work or not would depend on how much the 7.65 die sized down the neck. If the case were sized small enough, an expander for .308 would work.
As you know, a conventional fl die sizes the neck smaller than necessary, and then the expander brings it up to size as the case is drawn over it.
 
tiriaq said:
Whether this would work or not would depend on how much the 7.65 die sized down the neck. If the case were sized small enough, an expander for .308 would work.
As you know, a conventional fl die sizes the neck smaller than necessary, and then the expander brings it up to size as the case is drawn over it.
Click to expand...

Who knows, maybe I wouldn't even need an expander at all. It is possible that the FL sizing die might already leave the neck tight enough to hold a .308 bullet.

I have contacted a couple of smiths and they seems to be able to do the work but they all agree that they will have to order a apeciial reamer and this costs $$$.

So far the project seems viable but costly. The only thing that is starting to concern me now is that I would basically be left with a wildcat cartridge that is neither a .308 Winchester nor a 7.65 Argentine.
 
Hey, guys, it's only 3 thou that the argument's all about: thickness of the average human hair. LOTS of reloading dies size the necks that much too far; that's why we lubricate the inside of case-necks in the first place.

I, too, can load .308 slugs into a .303 case with no trouble; just change the expander ball.

Yes, you will have a wildcat, but it will be a wildcat with a .30 slug on a 7.65 Argentine casing. You have slightly more case capacity and pressures with any given load should be below what they would be if the same charge were fired in a .308W.

Do it, take it home, play with it, shoot it a LOT and then, when the barrel starts to wear out, shoot .310 slugs out of it. A lot of guys miss the simple fact that you can tighten up the shooting of a LOT of worn barrels with an oversize slug.

That's why I just can't understand why the Americans INSIST on making .303 bullets at .311" diameter. The Brits PROVED..... a flipping CENTURY ago...... that .312" gives better accuracy.... and some custom bullet makers even make them in .313" and .314" for well-worn old rifles. You're just doing the same thing, but this one will be YOURS and it should outlast you AND your son.

Have fun!
 
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I have a 1909 argentine with an excellent bore, but it was one of the unfortunate victims of a 30-06 reamer.

Can I use a 303 expander in my dies and basically make it a 303-06?
 
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