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

Crown over B notes that the sporting weapon experienced proof in the final state.

Kind Regards,

Raimey
rse

I think Axel is probally correct and I bet this is the D case, I could measure one for you every half inch from the rim forward and you could compare against your casting if you would like, it would have to be later today after I get home, then you would know that you needs dies for the D case.

m-4

Ford's take on it:

"Axel is exactly right about what his problem is. He doesn't have to buy a reamer or special dies, unless he just wants to.If he sizes the case, at the point of intereference, so that it chambers; it will fireform to the chamber. Then, normal dies can be used and will work well as "neck sizing dies". He shouldn't have a problem with the expander button, since his groove diameter is .366. If it had been smaller,he would have had to go to a 357 expander. I loaded a lot of 9.3x72R ammo using 9.3x74R dies this way, and 9.3x62, x57, or 35 Whelen could be used by setting them above the shellholder and using the right expander....

I would try 38-55 Win. die, so the bullet would clear and maybe the body would be sized enough since the head size is a few thousanths smaller than 9.3x72R. I would do it by feel and mark the cases like he did to find the problem. Or he could pull the bullets, resize, then reload. This is a lot of trouble, but only has to be done once for each case and he would save custom dies or a reamer."

Or just drop it by Ford's house & he'll ream it for you. Email me and I'll connect you to Ford as he hasn't received your note. I realize that many have been converted or altered by I wouldn't take one metal shaving out as the above described method works fine.

Kind Regards,

Raimey
rse

Thanks for the proof comfirmation Raimey.

I have dies from CH-4D and we tried a sized case. The measurement difference between the chamber and the resized (or factory S&B) is .007 narrower just below the untapered area leading into the neck (which is about .380) It would have been great if the factory dies would have bumped it down far enough but not so.

I agree that as long as everything is true, the full sizing can be a one shot deal and after that it is all in the neck if using reasonable loads.

Tom

Would appreciate that when you get a chance.


thanks,

Rob

Hi Rob,
We went through this before in post #243316 & my finding were as noted in the responce below.

Raimey has called me out! I have about a 1/2 dozen guns in the 9.3x72R chambering & over 500 rnds of ammo & brass and I have a habit of collecting vintage ammo as well as guns, so I went up into the loading room and pulled 4 boxes of factory vintage ammo for measurements, my measurements were just taken with a pair of Brown & Sharp dial calipers so not exact. 1st recomendation is to get a copy of the 3 part article Mike Ford wrote for the GGCA and read it carefully as it is stuffed with lots of info for this fine cartridge. Let me start by saying the same factory cartridges will not fit in all my guns and I always drop each round from the selected box into the chamber of the rifle I am going to use it in so I don't end up with any suprises in the woods.If I were to grab one of my tight chambered early guns I found that the vintage old Norma 10 rnd boxes of 9.3x72R D with the red labels usually seemed to be the most universal in fitting all the guns, so taking these measurements even suprised me a bit. Measurements were, rim dia., then each 1" increment toward the mouth, then case mouth dia., & last bullet dia.

DWM 9.3x72R .483 .425 .403 .382 .380 .363 bullet

RWS 9.3x72R .483 .425 .405 .382 .382 .367 bullet

Gedaco9.3x72R NORM .483 .423 .400 .385 .383 .365 bullet

Norma 9.3x72R D .480 .427 .405 .385 .382 .365 bullet

DWM Handload .483 .425 .403 .383 .384 .364 bullet

I geuss the biggest lesson learned in this little exercise is that just a couple of thousands of an inch dia. in a long slow tapering case such as this makes a big difference in fitting the chamber and that ammo specifications at the turn of the century were not as exact as todays expectation. Folks were able to purchase manufacturers brand of ammo that the chamber was cut to and the gun regulated to! 100 years later and halfway around the world we have to learn to accept this and experiment and test various available ammo or take a good casting & have dies made for the chamber being used today. Get a good casting & slug your bore & take notes, once you know what you have and obtain you components its time for the fun to start! Feel free to contact me if I can be of any assistance.

M-4

M-4, somethings fishy! You can only take 2 measurements on the case if you're using 1" increments, then you're on the bullet. Did you mean 1/2" increments?

Rob,
Excuse me you are correct, measurements at 1/2" increments. Also looked up Fords article in the Waidmannsheild (GGCA) 3 part article in 2009, WA#39 pg 22, WA#40 pg 5, WA#41 pg 6 on the 9.3x73R

m-4

Here' are my measurements taken with 2 dial calipers, same readings from both. Casting is Cerrosafe, about 30 hours old so within the window of accuracy.

Rim had to be taken from the gun, not the casting, .490 but remember only 0.040 deep.

Base .430

.5" - .414

1.0" .399

1.5" - .392

2.0" - .389

neck -.387

Bullet -.366

M-4's eyesight must be slipping as he is a year older today I believe.

Kind Regards,

Raimey
rse