7.65x53 Brass Forming

Hello chaps

I have a reloading query here. I want to make 7.65x53 mauser (for the Argentine and Belgian Mausers) cases from a more available calibre. I tried using a Lee 7.65x53 full length sizing die on 30-06 cases and then trimming, but the resulting cases wouldn't chamber. I contacted Lee Precision and they said that full length sizing dies are not designed to form the desired calibre from a different one, and I also found that a few others had this problem caused by the Lee die not pushing the case shoulder down far enough.

Looking for a solution, I found one reference to someone using 308 cases which are a little too short but could essentially be fireformed to become 7.65x53 - link here: https://www.thehighroad.org/index.php?threads/7-65x53-argentine.675310/
(final comment)

My question is, has anyone else tried using this method with 308? Does it work, or can anyone suggest another solution? I'd rather not purchase the PPU brass if I can help it. I'd also prefer not to purchase any more dies. Any help is much appreciated.

 

I use .30-06 shells and RCBS FL dies and it does fine. But the final case is a bit short of what factory cases are ... not much but ~ 0.5 to 1mm short. They work fine for me with some Hornady 150s and IMR4064. Since .30-06 shells are short, there is no way .308s will work.

 

Are you annealing? Handloader's Manual of Cartridge Conversions shows:
Use .30-06 brass.
Trim to 2.1".
Anneal and full-length size in the Mauser die.
Trim and chamfer.

 

I like Lee dies, but I've had lousy luck when using them for major case reforming operations. Most of my problems have been caused by the oversized bleed holes Lee uses.

You might try sizing, rotating your cases 180 degrees and running them into the die again.

Do you have your sizing die set up to "cam over" the press?

I recommend that you try to work out the problems with forming from 30-06. I haven't looked at the actual dimensions, but I'd be worried about excessive headspace fire forming a .308 case in a 7.65x53 chamber.

The only way that 30-06 (7.62×63) cases would be too short when formed into 7.65×53 cases is if you trimmed them too much.

 

I went the simple way. PPU makes loaded 7.65x53mm ammunition and cases. I only seem to find it online (not at local store) but then a set of Lee dies and I was set. Powder and primers are pretty much what I have anyway and bullets are the same size as .303 British. (Looking at the data, so are the ballistics.) That does not directly address your question of forming brass, but worked out well for me.

 

That's possible. I may have trimmed them prior to reforming. I just remember the final product being a smidge too short.

 

I actually went to the CIP website and compared the dimensions of .308 and 7.65x53.

https://bobp.cip-bobp.org/en/tdcc_public?page=1&cartridge_type_id=1

They don't give lengths to datum line, but going by length from the head to the beginning and end of the shoulder, it looks like you'd have at least 3, and possibly more than 4 millimeters of excess headspace.

You could safely convert .308 cases to "too short" 7.65x53 if you necked 'em way up and then formed a false shoulder to fireform, but that'd be more work than converting '06 cases.

Just necking up .308 cases to take .312" bullets and shooting them in a 7.65x53 (as suggested in the post you linked) would be a dangerous and even stupid course of action. Your headspace would be entirely dependent on your extractor.

Just take a look at the C.I.P. dimensions for each of them and judge for yourself.

 

Hornady loads 7.65x53. That would be better brass for reloading.

 

Jean-Luc, Your empty '06 case don't chamber because they probably need more sizing. Turn the die in more, an eight turn and more if needed. Push that shoulder back more. Castor oil might be good for you. By the way it isn't resizing, It is Reforming brass and it may take some extra leverage.BestoLuck

 

I'll give rotating a go. I'm afraid I don't know what 'cam over' means.

The cases won't go any further into the die. It bottoms out. I'm thinking I will try to remove some material from either the shell holder or the die itself so that the case can go further into the die.

Okay I'll avoid using 308 brass then. Shame as it's so plentiful.

Thanks for the replies all!

 

Jean, I'll still say your brass has not been reformed enough. So the die is all the way in with no gap and no brass in the press. But I'd bet that when you put the brass in for reforming, you can see a gap between the shellholder and the die. Bottom out the die as you have done, then the lower the ram and turn the die in further(1/8 turn or more) until the cases reform properly and chamber. Removing metal from die or shellholder is not a good idea.Best