9mm to 308

[gvanzeggelaar]

Hi All,

I am wondering if it would be possible to cut the rim off of a 9mm case and swage it down to .308 diameter using a series of sizing dies. Anyone ever try doing this.

Thanks,

[Bwana]

It has been talked about before and would probably require a second, and possibly a third annealing before final forming.

[Artful]

9mm would be better candidate for 375 cal - 30 carbine make 358 cal pretty easy.

[BT Sniper]

Anything is possible! I'll just use the FN 5.7x28 brass for jackets though. I would bet at least 3 draws to size down with anneal inbetween though for the 9mmx308

[Bollocks]

Hi,

I draw 9mm cases first to .353 en then to .306. No second anneal.

Chrs,
BolloX

[coleman]

http://castboolits.gunloads.com/showthread.php?t=92578&page=2

[bohica2xo]

Hi,

I draw 9mm cases first to .353 en then to .306. No second anneal.

Chrs,
BolloX

You can do that with your Corbin press, but I do not recommend that with a reloading press.

I can skip the anneal all together if I stuff them through the punch press, and go straight to .306 from a fired case.

What I don't understand is the aversion to multiple anneal cycles. It is not hard or expensive to re-anneal, and cleaning is not necessary until the jackets are ready for the final draw or core seat.

B.

[Bwana]

Drawing them down without annealing would make the brass harder and this would interfere with the jacket peeling back at the same rate as the lead causing core seperation upon impact.

[sargenv]

Since all I do is punch paper with rifle bullets or ring steel.. core separation is a moot point for me.. but I can see where that might be a concern in a game bullet.

[Bollocks]

You can do that with your Corbin press, but I do not recommend that with a reloading press.


You got a good point there.

[gvanzeggelaar]

I am planning on using a rockchucker press and lee sizing dies. Does anyone have a problem with the case turning sideways a bit when going into the die.

[MIBULLETS]

The cases usually straighten themselves out as they hit the restricted part of the die when pushing the case head in first. If you put the mouth in first it might tip some more. The way they are made to work, the punch pushes them in mouth first, but if you make a longer punch that fits into the jacket you can size them head first.

One thing about the Lee size dies, if they are stock, your jacket has to be fairly close to the corrct size before going into the die. If you can open up the die entrance some and smooth out the lead to the actual final sizing portion, you could size a larger jacket down.

[gvanzeggelaar]

Ok ill see if I can ream them out a bit.

Thanks,

[Bwana]

To size the 9mm cases down to 358 you can use a Lee steel taper crimp die and size them head first. If your rod is long enough you could push them all the way through. Use a good lube and there's no problem. This is after a full anneal of course. No need to clean the cases after the anneal. Look up my procedures in my Hybrid bullet posts on this site.

[Bollocks]

FWIW,

last week I recieved some Lee bullet size and taper crimp dies to play with. The bullet sizers are too rough and need work. The 9mm taper crimp die sizes my cases to .360

My main die for sizing the 9mm cases down is a modified Dillon taper crimp die. The 9mm cases come out at 0.354. I can then swage .355 bullets in one step using the C4H point former.

Chrs,
BolloX

[MIBULLETS]

The Lee bullet sizers are just that. They are made to size lead bullets that are only a few thousandth too large from a mold. The internal part of the die is fairly smooth, but right at the mouth of the die, there is a short tapered section to guide the bullet into the sizer. This is the area I said needed to be opened and polished up so that larger brass cases can easily enter the die.

[sargenv]

This is the area I said needed to be opened and polished up so that larger brass cases can easily enter the die.

How would one do this? I take it a lathe may be required with some sort of progessive reamer or taper cutting tool? Then there is the question of polishing.. I'm interested in doing something like this.

[gvanzeggelaar]

The dies are quite hard so I'm not sure what you could drill them with.

[seppos]

Properly sharpened glass drill or diamond bit works with hardened steel.
http://teakdoor.com/Gallery/albums/userpics/10332/TILE--GLASS-DRILL-BIT.gif

S

[BT Sniper]

The lee push threw bullet sizers are easy to opern up that taper section. I really doubt teh die is that hard. I know I did a few of mine a while back. Think I had it in a lathe and used a dremmil carbide cutter to smooth things out.

Are you guys interested in sizing dies? I know a source but would have to see if any are still avialble.

BT