Case forming 7.65 Argentine from 30-06. Which die works?

I bought a RCBS case forming die for the 7.65 Arg for my 1891 Argentine. I formed the cases from WWC 30-06 new brass and then ran them thru a Lee sizing die. When I try to chamber a case the bolt will not shut. I have seen in older posts that the Lee die is for the Belgian & Argentine and that the Belgian chamber is a little larger. Unfortunately I managed to get two sets of Lee dies which I now cannot use. Are there any other dies made by someone that are only for the Argentine that will work without moding. I have seen where some one has shortened the Lee die and it worked but I don't think that I have the equipment to accurately do that or know of anyone that can do it for me.
Thanks

It's not an issue with the die per se. The hardness of the case in the area where the new shoulder is formed is harder than a neck/shoulder area is on a factory case. You can try annealing the case in this area prior to forming. Just be careful that you don't let the base get too hot. If you've never done annealing before, read up before attempting it.
Working the brass, ie: forming and resizing, hardens it. Annealing softens it. Only the neck and shoulder area should be annealed.

Or you can do this.
Take .005 off the top of your shell holder. Mark the shell holder for this purpose only. Use a good lanolin based lube like Imperial Sizing Die Wax.

You could also buy a set of the Redding shell holders that are in .002 increment different thicknesses, but they are pricey.
Redding Competition Shellholder Set #1 (308 Winchester 30-06

Finally, anneal the case necks when you are finished reforming them. They will crack if you don't.

Graf & Sons has new Prvi 7.65 brass for $60/100. After you reform/trim/anneal 100 cases, you will probably wish you just bought new ones.
Graf Sons - PRVI PARTIZAN BRASS 7.65x53 ARG. UNPRIMED 100/BAG

You may have to inside neck ream also as the case will be thicker there now. If you've seated bullets, it's like the snake that swallowed an egg...too fat. Also you will have to reduce the load by a bit because the remaining case will be thicker and not have as much inside case space.

Quote:

---

Originally Posted by no4mk1t

The hardness of the case in the area where the new shoulder is formed is harder than a neck/shoulder area is on a factory case.

---

Why would this keep a cartridge from seating?

Quote:

---

Originally Posted by browningautorifle

You may have to inside neck ream also as the case will be thicker there now. If you've seated bullets, it's like the snake that swallowed an egg...too fat. Also you will have to reduce the load by a bit because the remaining case will be thicker and not have as much inside case space.

Why would this keep a cartridge from seating?

---

Hard brass has a spring back property to it. This is what makes extraction of the case easy and why "cartridge brass" (70% copper/30% zinc) is used for cartridge cases.. Upon firing, the case expands and seals the breech, (its primary function) then the case contracts slightly and releases its grip on the chamber walls.
This same spring back occurs when reforming the case. You either have to push it slightly further into the die so after springback, the case will chamber properly, or anneal the area where the new neck and shoulder will be formed to make that area soft. The annealed area will then not spring back.
All in all, a lot of effort. You have to do it for antique arms where cases are no longer made, but if new factory brass is available at a reasonable price, it makes more sense to buy.

Quote:

---

Originally Posted by no4mk1t

This same spring back occurs when reforming the case.

---

IE metal has a memory. Same as barrel straightening, go past the bend and then it returns to straight. I've been reloading most of my adult life and have had lots of obsolete stuff requiring case reform. For me, the cheapest way to effectively load makes thee most sense.

I still think he may have other issues to deal with.

Quote:

---

Originally Posted by browningautorifle

I still think he may have other issues to deal with.

---

Maybe so. We will have to wait for him to report back and weigh in whether or not anything posted proved helpful. A cursory Google search indicates that he is not the only one having that issue reforming 30-06 to 7.65 though.
He may not have been aware that new brass was available and may abandon the attempt to reform them from 30-06. I would.

If you can't find "proper" 7.65 brass and have a little time up your sleeve, try forming these cases from 7.92 x 57 brass, new, preferably, and also available from our Serbian cousins.

Not nearly as much "extra" to trim off and any neck reaming will be somewhat less arduous than if the cases are formed from .30-06 brass.

The usual caveats about annealing (perhaps before and definitely after) still apply, though, if you want decent case life and "ease of working".

Shortening .30-06 cases was the norm back when the world was awash with ex-mil brass; sadly, those days are gone.

Are you lubing the inside of the case neck before running it through the sizing die? If not the expander may be stretching the shoulder enough to prevent chambering.
And I assume you're using a FL sizing die and not a neck sizer?
I never used a form die when converting 30-06 and similar brass to 7.65x53mm. I just lubed the cases good inside and out, ran them through an RCBS FL sizing die, rough trimmed, annealed, final sized/trimmed and loaded. Never had any not chamber or give any other troubles. I'm still loading some that I made up 25 years ago.
I preferred Remington or Winchester cases, Federal and military brass was thicker and sometimes required neck reaming.

Quote:

---

Originally Posted by vintage hunter

. . . I never used a form die when converting 30-06 and similar brass to 7.65x53mm. I just lubed the cases good inside and out, ran them through an RCBS FL sizing die, rough trimmed, annealed, final sized/trimmed and loaded. Never had any not chamber or give any other troubles. I'm still loading some that I made up 25 years ago.

---

Yup, same here - except I never found a need to anneal these until after a half-dozen or so reloads. (Also never had brass so thick or chamber so tight as to need neck-reaming.)

https://www.milsurps.com/images/impo.../33upoog-1.jpg
US military .30/06 anneal extends far enough to include 7.65 shoulder.

I'd venture that mrappe's problem might be traced to press spring during the FL sizing operation, perhaps combined with inadequate case lube. This can be addressed by adjusting FL sizer down about 1/8+ turn beyond no-load shellholder contact, and using castor oil as sizing lube.

https://www.milsurps.com/images/impo...7/1f8uwz-1.jpg
Visible gap during actual sizing indicates die might need to be adjusted down to compensate for press flex.

I agree with Bruce, 7x57 & 7.92x57 are a lot easier to work with !...................

7x57 is a tad shorter-bodied than 7.65. May present minor headspace issues that can be addressed by several standard techniques, all more or less time-consuming.

https://www.milsurps.com/images/impo.../2wn7m6s-1.jpg

.30/06 is easy - and readily-available, free or cheap. Never tried 8x57 - not much free boxer brass around here.

7x57 could be used in a pinch I reckon but it would require the extra step of fire forming or else you'd likely end up with excessive headspace and it's related problems.
I've used 8x57 brass to form 7.65, the forming part works out fine but of the 20 pieces I used 7 or 8 lacked enough neck tension to hold the bullet in place during recoil. A few were so loose I could seat the bullet with finger pressure only.
30-06 or 270 works best and requires the least amount of effort.
Even though new factory brass is available from PRVI now I don't like to discard brass unless I absolutely have to so it's a good way to get a few extra miles from suitable cases that would otherwise be destined for the scrap bin due to split necks. That's the biggest reason why I incorporate the annealing step in the conversion process.

I tried taking out the expander-decapper from the die and then put a 0.014" feeler gauge into the bottom of the shell holder and ran the case up again in the die after annealing it and the empty case then chambered easily into the rifle. I tried loading a bullet (Moyer's cast lead gas check 303 Brit 313 dia. 180 GR FP) into the case without primer/powder and the neck bulged on on side and was too tight. I then re-sized a case with the feeler guage with a whole in it for the pin and was able to seat a bullet evenly OK. I tried several and the rounds chamber OK with just a little tightness when opening and closing the bolt. I am still trying to determine if the necks need to be reamed/thinned as every once in a while some of them are tighter when removing as the bolt turns.

If necks are too thick, you can feel the resistance when slowly moving the bolt the last 1/4" or so forward to chamber the round. (Remove the striker assembly first for safety and better sensitivity.) After extracting, you should be able to see evidence that the surface of the neck has been scraped as it enters the chamber neck. But - the standard way to check for thick necks is to try inserting one of your bullets in a case neck after firing with a load generating sufficient pressure to expand the case fully (squib loads won't do). If the bullet passes easily through the fired case neck, that indicates the neck is not too thick for bullets of that diameter or less.

Instead of inserting a feeler gauge between shellholder and case, it's not hard to simply remove some metal from either the top of the shellholder or the bottom of the die. Either can be accomplished with nothing more than a few sheets of 180-grit wet/dry abrasive paper on a hard surface like a kitchen counter top. Just apply enough light oil to keep the paper from clogging and rub the die bottom or shellholder top around on the paper in a circular motion for a few minutes, checking frequently with a good caliper. Try sizing a case every time you take off about .003". Stop when the case chambers easily. This is not difficult and requires very minimal investment. (Make a notch on the outside of the die mouth or shellholder top to remind yourself it's been customized and isn't for general use.)

If you haven't yet checked for press-spring (looking for a gap between die and shellholder when ram is at top of stroke with a case being sized), do so first to ensure you're not altering die or shellholder unnecessarily.

Attachment 63994

When the Lee 7.65 dies first came out people found they are too long in the body so they will not size a case that will fit a 7.65 Argentine Mauser chamber.
The following is an investigation of the dimensions of my rifle chambers, reloading dies, factory ammo, factory brass, resized cases and a few fired cases and etc.

I have 4 rifles - 3 M1891 and a 98/09 .
This is what the chambers measure using a .375 diameter gauge ring in a Hornady gauge attached to my calipers. The set up was corrected to zero with a 7X57 gauge to minimize any shoulder angle and chamfer issues found on the tool. You will see that I cross checked these number several ways to avoid any silly errors.

This is the dimension (for each of the 4 rifles) from the bolt face/case head to the gauge diameter on the shoulder of cases that barely drag when the bolt is closed.
1.822
1.821
1.820
1.820

AMMO and virgin brass
PPU ammo measures 1.819 to 1.821. It is excellent for my rifles. This ammo might NOT chamber in a CIP minimum chamber
New PPU unfired brass measures 1.818. Ditto
New Norma factory ammo measures 1.812 to 1.816 (more variable and a little shorter than the chambers) You can see below that it more nearly matches the CIP minimum drawing
New Norma unfired brass measures 1.815 ditto for the Norma ammo comments

Reloading dies
These sizes were all taken with the FL sizer or trim die down hard againt the shell holder. The same shell holder was used for all the dies. The shell holder measured exactly .125 deep.
Each case was cycled in and out of the dies 4 to 6 times without an expander until I thought the brass was not moving the shoulder back any more. At the end of each sizing stroke I let the ram dwell in the up position for 3 to 4 seconds so the brass had time to creep and take a set if it was still moving. My goal was to duplicate the inside length of the die as exactly as possible using FL sized brass.
Most of the cases formed were commercial once fired .30/06 that had been trimmed. If you cycle your brass only once during FL sizing it may be .002 longer than my results. I was using a RCBS Rockchucker press.

The Lee FL sizer measures 1.838" using the same .375 gauge diameter on a FL sized case. This is way too long - about .018 to .020 too long.

I have 2 RCBS FL sizer dies that measure 1.818 and 1.819. Just right in my opinion for my chambers.
I have another RCBS die - this one is a trim die and it measures 1.816 - Again RCBS gets it about perfect.

I have a modern Lyman FL die (less than 10 years old) an it measured 1.814 - a little bit short but....more later

I have a set of older Pacific dies and they measure 1.797 - not even in the right ball park avoid these at every opportunity. They are way the heck to short - even dangerous.
I have an old CH trim die that measure 1.781 - even worse. These cases might separate when fired. This die was not made by the current CH die company but it predecessor

Gages drawings and headspace gauges
I also have a Wilson Case 7.65 Mauser case gage that checks from the head to the shoulder. Wilson gauges are well known for exacting accuracy. My formed cases agreed with the Wilson tool and it agreed with the RCBS dies. Other Wilson gages also agreed with my Forster headspace gauges in several other calibers mentioned below.

There are no SAAMI documents for this cartridge but there are CIP drawings. The only problem is the CIP drawings are dimensioned using a different datum structure and they are not toleranced.
Therefore I took the Minimum CIP chamber drawing and used the conventions for SAAMI GO, NO GO and Field gages and applied them to the CIP minimum drawing.
To get the dimensions to the .375 gauge ring I had to create a spreadsheet that could calculate the SAAMI numbers from the CIP numbers because the geometry that locates the shoulder is defined in a different manner.
To test my spreadsheet trigonmetry I double checked some of the CIP drawings for American loaded rounds against the SAAMI drawings.
The test drawings included the 6.5X55 Mauser, 7X57 Mauser and the 8X57 Mauser. I got exactly the same numbers. I used those three because I also have a Wilson case gage for each and a set of Forster headspace gages for each. I can tell you that the Wilson Gages, the Forster go gages and my numbers agreed exactly to within .001. They are even better when comparing with a .0005 dial test indicator.

Here are the numbers for the CIP 7.65 drawings

Minimum chamber 1.816 I called this the GO gage length. This is the number calculated directly from the CIP MIMIMUM Chamber drawing. This seems to be the target for the Lyman FL die.

No go chamber 1.820 I just added .004 for the NO GO (If you add .005 the number is 1.821 for some SAAMI gauges the steps are .005 but I prefer .004) Seems to be the target for the RCBS dies.
Field chamber 1.824 I added .008 to the min chamber (If you add .010 the number is 1.826)

I have used my personal judgment in the No Go and Field dimensions. If you prefer you can use your own numbers.
My goal was to determine all I could from my dies, my ammo, my brass, my chambers and the existing standard CIP drawing.
Since I control my ammo head to shoulder dimension when I reload it I know what dimension to make it to fit my rifles.

I also know what dimensions Norma and PPU ammo and brass are produced at.
I also measured 2 of the SF 81 Argentine military cases at 1.820. Both of these cases seemed to have the wrong shoulder shape and chambered tightly in my rifles.

For my rifles I will load with the head to datum length set at 1.821. If that is too tight for the two tighter rifles then I will load them at 1.820.

Finally case length over all

CIP Min is 2.110 CIP max is 2.114

My chambers measure around 2.125 I will trim my cases when they are longer than 2.122. I get a little bit longer neck this way.
There is no danger from this. If the case if FL resized, when it is fired it will shorten .004 to .007. It will lengthen when resized. Always check your cases for over length each time they are reloaded if you decide to leave them long.

If you have one of the Lee dies that are too long you can get it cut off so it produces brass to fit your rifle.
You should have the capability to measure your chamber and your die before modification. Otherwise you are going to be doing a cut and try process that may not work so well if you are not careful.

You can also complain to Lee and see what they say.

From my measuring and checking RCBS dies are the way to go.

Quote:

---

Originally Posted by ireload2

From my measuring and checking RCBS dies are the way to go.

---

They always have been. Lee is cheap so thus the problem.

Quote:

---

Originally Posted by browningautorifle

Lee is cheap so thus the problem.

---

I have no qualms with Lee dies. About half of the 50 or so die sets I own are Lee. Besides the occasional broken de-capping pin that can happen with any brand they've all worked flawlessly for me and the ammo loaded with them is just as uniform and accurate as that loaded with RCBS, Redding or Lyman. I had an RCBS FL size die that split from stem to stern once. Never had that happen to any of the cheap Lee's.

Quote:

---

Originally Posted by ireload2

The Lee FL sizer measures 1.838" using the same .375 gauge diameter on a FL sized case

---

Unless you gotten the same results from multiple sets checking just one example isn't enough to rule out the possibility of an out of spec die.

Quote:

---

Originally Posted by mrappe

I tried taking out the expander-decapper from the die and then put a 0.014" feeler gauge into the bottom of the shell holder and ran the case up again in the die after annealing it and the empty case then chambered easily into the rifle.

---

Sounds to me like his problem was a sloppy shell holder rather than the die.

The original poster and at least a half dozen others on other forum over the last 15 years have complained about the Lee die for this caliber.
If you carefully read the original posters comments he stated that he had 2 sets of Lee dies with this problem. And then I checked mine and I find the same problem so it is not a single die. The problem is Lee does not always do his homework. Lee could at least buy a set of RCBS dies and a set of Reddings and a couple of 1891 Mausers before he determines his final die dimensions. Many or most Lee sizers are very close to the same dimensions as RCBS but the 7.65 Mauser made by Lee is wrong.
I have spent a good bit of time and money gathering all these dies and forming cases so I can measure the dies and my chambers. I am not willing to spend more money on another Lee die when I know that another brand is more dependable in this caliber.

Quote:

---

Originally Posted by vintage hunter

Unless you gotten the same results from multiple sets checking just one example isn't enough to rule out the possibility of an out of spec die.

---

There is a very easy way to measure your chamber NECK diameter.
Take one of your successfully formed cases and use a tapered punch or equivalent ( I have used a FMJ bullet too) to expand the case mouth .020 to .030 oversize - all you need is a trumpet shaped mouth. Take this case and chamber it. You will have to force the bolt handle forward a little to get the trumpet to squeeze down into the chamber neck.
Extract the case and measure the compressed edge of the trumpet. That will be your neck inside diameter. To get a major warm fuzzy you can measure it 3 or 4 times and get the same number.
I think you will find there is plenty of room for almost any brass on the planet.
I have several hundred US military SL-54 cases that I have formed for my rifles and it works fine in all of them.
Just be sure to anneal or you might get cracked necks within one or two reloads.

My cleanest 1891 Mauser measures .348 in the neck at the case mouth.
The ammo that I have loaded with the SL-54 military brass measures .338 to .340 over the case neck with .311 and .312 jacketed bullets.

Your use of the feeler gauge under the case head is good evidence of the Lee die interior being a little too long.
Send me a PM with your location. We might be pretty close. I am in the center of the state. I have access to a lathe and can cut off your die when I cut mine off.

Quote:

---

Originally Posted by mrappe

I tried taking out the expander-decapper from the die and then put a 0.014" feeler gauge into the bottom of the shell holder and ran the case up again in the die after annealing it and the empty case then chambered easily into the rifle. I tried loading a bullet (Moyer's cast lead gas check 303 Brit 313 dia. 180 GR FP) into the case without primer/powder and the neck bulged on on side and was too tight. I then re-sized a case with the feeler guage with a whole in it for the pin and was able to seat a bullet evenly OK. I tried several and the rounds chamber OK with just a little tightness when opening and closing the bolt. I am still trying to determine if the necks need to be reamed/thinned as every once in a while some of them are tighter when removing as the bolt turns.

---

Quote:

---

Originally Posted by vintage hunter

I have no qualms with Lee dies.

---

You've been lucky then. I only have one if I can't get better. Then I replace it soonest. I have lots too. I've seen nothing but problems so I'd never use a Lee product as a regular item. None of it... One RCBS item failed? That's not bad.

Good News:
I recieved the Lyman die set that I ordered in 7.65 Argentine and tried a case with it after using the RCBS case forming/trim die and trimming the case. I loaded the brass with a bullet using the Lyman seating die and it chambered and extracted easily. It looks like I will not need to turn or ream the case neck after all.

The RCBS trim dies are .010 larger in the neck than the RCBS FL die. If your brass is thick enough sometimes the trim die can be used as a FL sizer and will not work the brass so much. You may not need the expander but you would have to decap with a hand tool.

Quote:

---

Originally Posted by ireload2

The RCBS trim dies are .010 larger in the neck than the RCBS FL die.

---

He's right. If you were having trouble I'd bet it's because you didn't properly full length size after the trim die. I just went back to post #1 and see that you call a trim die a case forming die. It ain't. It's a trim die. Then the Lee die after only compounded the problem. No wonder it wouldn't fit. Glad you have it sorted out now.

And if you don't have a proper heavy-duty press to form them with ( at the time my little Lyman Spartan C wasn't up to it) use a vice. Lube the case insert it into die , decapping rod removed, slip shell holder on case rim as a stop, then slowly close the vice jaws, making sure everythings lined up , Of course you have to use a rod and mallet to drive the case out of the die .
I once formed 7 X 57 cases out of 30-06....I was young and had thousands of once fired military cases. Still not a great idea.
Gary

Quote:

---

Originally Posted by gwpercle

Still not a great idea.

---

Exactly.

One case worked in the Lyman Die but the case was not going al of the way into it. The next case got stuck in the die and when I tried to lower the ram the case rim sheared off. I had to dig the case out and the expander's threaded rod got bent. It looks like I will need to turn the outside of the neck to get it to work. I ordered a Forester hand held neck turning tool since they were the only one that I could find with a 311 mandrel for.

Quote:

---

Originally Posted by mrappe

The next case got stuck in the die and when I tried to lower the ram the case rim sheared off.

---

A classic example of not enough case lube...there's a removal tool for that to make it easy.

Quote:

---

Originally Posted by browningautorifle

A classic example of not enough case lube

---

Yep. Can't be stingy with the lube when forming cases, or so I learned. The hard way.

Quote:

---

Originally Posted by browningautorifle

there's a removal tool for that to make it easy.

---

Or, you could make your own.

Yup, it's almost spot on for the factory...truth be told, you seem to need the tool every other session until you buy it. Then you almost never need it. Like twice in 20 years...

Yep! It's a bit like the various "extensions" of "Murphy's Law":

1. If you can't find something you KNOW you have, go and buy another one. The original will be staring you in the face when you get back from the store.

2. Incoming "friendly fire" is more accurate than incoming enemy fire.

3. "Quick-release" mechanisms won't.

4. Always remember: "Murphy was an optimist".

And a few "variations":

Law of Selective Gravity: An object will fall so as to do the most damage.

Jennings' Corollary to the Law of Selective Gravity: The chance of the bread falling with the butter side down is directly proportional to the value of the carpet.

Wyszkowski's Second Law: Anything can be made to work if you fiddle with it long enough.

Sattinger's Law It works better if you plug it in.

Lowery's Law: If it jams - force it. If it breaks, it needed replacing anyway.

Schmidt's Law: If you mess with a thing long enough, it'll break.

Anthony's Law of Force: Don't force it - get a bigger hammer.

Cahn's Axiom: When all else fails, get the instructions out of the bin and read them.

Speaking of Murphy's Law, a friend's cousin Capt. Edward A. Murphy is the person whom is credited with coining the law and who's name it came from.

FL reloading die tolerances cause some variation in the diameter of the sized case body.

I check the body diameter in two places by FL sizing cases and then measuring the case diameters.
1. Bright pressure ring at the junction of the solid case head and the case walls.
2. About .030" back of the shoulder corner.
At the shoulder dia. At the pressure ring
The Lyman FL measures .423 .466
The RCBS trim measures .428 .467
One RCBS FL Measures .430 .465
One RCBS FL measures .425 .466
The Lee FL measures .425 .466
The Pacific FL measures .425 .466
The CH trim measures .426 .467

As you can see the diameters are pretty consistent. Most of the variability was covered in my previous post that discussed the headspace dimensions.

Based on the numbers above I would expect the Lyman FL die to require the greatest sizing force.
The least sizing force should be either the RCBS trim die or the RCBS FL die with the .430 shoulder. This is debateable though because this RCBS die also has the smallest base dia.

Anyway this data is offered as food for thought.
I once had 4 sets of Lyman dies that I bought for the old PA (precision alignment) seaters. Everyone of the FL dies too more force than my original die sets to FL size a case.
These were late 1960s Lyman dies. I mention this because you had a case rim pull off. Verify that you have a good fit in your shell holder because the 7.65 rim is a little different than the common .30-06 size unless you are actually using .30-06 brass. Be sure to clean any new size out and use plenty of lube on the first case and size it in 1/4" increments relubing the case with your fingers until the first case is completely sized. Be careful with the first 4 or 4 cases in a new die.

The surface finish and Rockwell hardness of the die also affects the force required to size a case
I have found that polishing a new die with 400 to 600 grit wet or dry silicon carbide paper used wet with a light oil produces a superior internal finish and reduces the sizing forces required. I do this polishing in a lathe so it might not be possible to duplicate the precision polishing by hand without damaging the die.

Cases that have been tumbled to the bright jewelry finish are also easier to size.

Quote:

---

Originally Posted by mrappe

One case worked in the Lyman Die but the case was not going al of the way into it. The next case got stuck in the die and when I tried to lower the ram the case rim sheared off. I had to dig the case out and the expander's threaded rod got bent. It looks like I will need to turn the outside of the neck to get it to work. I ordered a Forester hand held neck turning tool since they were the only one that I could find with a 311 mandrel for.

---

I just got a RCBS die for the 6.65 Arg and it seems to do the trick. Now my chamber easily.

Quote:

---

Originally Posted by mrappe

I just got a RCBS die for the 6.65 Arg and it seems to do the trick.

---

And there you go! Once again we find RCBS doing the trick...(7.65 though, not 6.65)