doublegunshop.com - home Forums General Discussion German & Austrian Sporting Guns @ doublegunshop.com 9.3x72? Chamber cast shows convex walls?

Thanks Raimey
OOp's I just grabbed that from a past post and messed up and nobody brought my mistake to my attention that time. Lot's of variations and why I have a variety of factory ammo, I have several 9.3x72Rs & each get's the ammo checked to the rifle before it ever goes into the woods! So far have 2 different sizing dies and will probally end up with more before all said & done. Fun old cartridge also!

m-4

My Drilling is an early 9,3x72R of the "D" or Deutsch form. RCBS dies for 9,3x72R are for the nomalised case and, like yours, my case so sized was left sticking out and the gun would not close. This is also what happens with any new manufactured case.

A set of dies from Dave at C-H did the job and I can size brass to fit. The D has a curved base for 40mm above the base,(rim). The E (for English)version has a straight taper to 50mm from the base. TYhe normalised is a hybrid form. Simply measure your cerrosafe cast every 5-10mm and you should know what you have. However, don't ask Dave for a D or an E but rather, send him the measurements or the cast or both.

The rim also varies. If it's a D you'll need to reduce it and this is best done from the top, using a spiggot so you're just taking off a small strip, not reducing the whole head. The latter would make the case weaker and also you'd need to recut the primer pocket deeper.

I have here copies of origional factory case drawings of both D and E cases but it's problematic attatching a copy.

Hi guys, I'm Mike Ford. I finally registered so I could reply directly and not just scream at the computer screen. All that is necessary is to size the case(maybe cartridge) enough to chamber,one time.Then it can be loaded easily with common dies. I wouldn't recommend someone else work on live ammo(for obvious legal reasons),but I would try it first,myself.I tried a live S&B(older berdan primed)round in my 38-55 sizing die, with decaper/expander removed. The bullet clears the neck,and it looks like the lower body might be sized enough to chamber in your rifle. If not,then you are no worse off.BTW if you have to thin the rim,using a spiggot as recommended by Kiwi is one way. Another is to use a 38-55 die,turned into a 7/8 14 threading die and chucked into the lathe.Insert the case into the die and push it with the tailstock. It won't go all the way in, giving you room to reach the front of the rim.Putting a radius on the front edge of the rim may be enough,depending on the space between the barrels and breech face.I wouldn't be afraid to thin it from the rear,and use pistol primers.Older drillings sometimes have trouble igniting large rifle primers anyway. Rechambering to the "N" chamber is the one rechambering job I support,for people that either can't or don't want to handload.After all, as Axel said, that is the purpose of the "N" chamber.You would be surprised at how little metal is removed.Whatever markings are on the barrel would still be correct.On the other hand,I can understand anyone enjoying loading for unsual calibers. Do I have everyone confused enough yet? If not I can talk about making a simple die to size the cases to chamber for fireforming.
Mike

Thank you for backing up the comment regarding the curved brass Kiwi. I was hoping that someone had the info on it.

I think that some testing is in order before reaming chambers and whatnot. It is a hammer gun with the transfer bar, so what if it doesn't light off rifle primers?
Once the chamber is reamed for modern brass, rifle primers are the only option. With the thin rim at least the opportunity to thin from the back and use pistol primers is there. Grabbing some cut off and trimmed 30-30 brass should solve the problem for testing either primer.
Also, with all of the differences in bore diameter, an interchangable pilot reamer is going to be a must so a lender may not work.

Tom

Tom,
Since you would turn the reamer by hand,it would be easy enough to avoid deepening the rim recess. You reported a bullet dia.of .366, so a solid pilot reamer should fit. If you had a .358-9 groove dia.Your concern would be well founded. BTW 30-30 rim will likely have to be reduced in dia to check primers. It may have to be thinned also.
Mike

Hey Mike. I picked the 30-30 because it had alot of material to work with. Should work as a good test cartridge for the primers. Hopefully it will have to be thinned to check and see if the pistol primers are the better option. I think that the bore diameter measured at .357, so if it the reamer did fit, the cleanup of the chamber would make shooting somewhat simpler.

Tom,
You'r right about the 30-30,plus the world is full of the cases.I use it for everything I can. I make 8.15x46R cases from it even though 8.15 is avaliable. I think the pilot of a reamer for the normalized case with .366 bullet will fit a .357 bore. It won't fit either of mine, one has .358 groove- the other is .359. Solid pilots can be easily reground with a toolpost grinder,or a "moto tool" setup in a boringtool holder. Of course you either have to own it or have permission.

Gentleman,

The rest of the story...

Seems everything hinged on whether the rifle firing pin would set off a rifle primer. Thanks to good friend and molder of young minds Tom Hall who turned a 30-30 case to the proper diameter and then thinned it down to .036 by taking metal off the front of the rim. My rim cut is .040 deep so the primer was about .004 below the rim. She fired right away and left a nice mark in the primer, a good solid hit.



This is a no name drilling, no marking at all except the proof marks, an E.W. and an R.R. It's going to be a hunting gun and I want things as simple as possible so I'm just going to have the chamber reamed to the Normalised version so I can use modern ammo and cases.

No one local seems to have a 9.3x72R reamer and the cost of having it done along with rental is about the same as buying a reamer so it would be more cost effective to buy a reamer than to ship the barrels out to have it done unless one of the members can make a suggestion. I was quoted $150 to clean the chamber up because the reamer needed to be rented.

I know some of you may disagree and if the gun had a makers name on it I probably wouldn't alter it but as it is I may even open up the right barrel choke.

Rob,
I have a reamer,but no FFL. If you or your "agent" can bring the drilling to me, it would only take 5 minutes to do the work, and I have a place within a short drive to try it out.Whether it is worth it, to avoid handloading(keep in mind that you can use standard dies after fireforming cases)is entirely up to you. The upside is that the work won't cost you anything. For whatever it is worth,I don't consider the chamber work an alteration since it wouldn't change any of the markings.
Mike

Mike,

PM sent.