After the CIP standartization 2000 there is a difference in size between the 500 Jeffery and the 12,7x70 Schüler !

Does anybody have a problem with that ?

Is there a difference between Kynoch and W.Romey ammo ?

I've got a CZ 550 in 500 Jeffery. Kynoch ammo will not chamber in it, Jamison brass slides in like it was made for it. I'm guessing (and that's all that it is) that the Kynoch ammo is built for the 12.7x70 Schuler. Rip will probably know

Thank you for your ansver !

I have a rifle from Ritterbusch built about 1998/1999 and use ammo from W.Romey or brass from Horneber for reloading , but from this time , before the "Standartization" .

Regards

FS

We puzzled over the 500 Jeffery history back in 2010:

http://forums.accuratereloadin...043/m/4101008731/p/1

Here is a very interesting drawing ALF brought to us first:



C.I.P. Specs:

12.7 x 70 (500 Schuler):
Shoulder Cone Angle = 39* 54' 22"
Shoulder Semi-angle = 19* 57' 11"
Date: 01-27-1998
Revision: 05-15-2002

500 Jeffery
Shoulder Cone Angle = 25* 13' 41"
Shoulder Semi-angle = 12* 36' 50.5"
Date: 01-12-1999
Revision: 05-15-2002

Hi Rip, I don't doubt you a bit, but would like a little help understanding why the Kynoch ammunition would not chamber in my CZ 500 Jeffery. I've also heard the same thing from two other CZ owners. I only bought one box of 5 figuring to start out with factory ammunition, but because of the fact that they would not chamber went straight to handloading using Jamision cases which worked very well.

Thanks!

chuck375,

The fact that your rifle was too tight for a certain ammo seems to indicate it must have the proper C.I.P. spec for 500 Jeffery, which is tighter in the shoulder area than 12.7x70 (500 Schuler).

But that would mean that the Kynoch ammo was out of spec, if it was supposed to be for the 500 Jeffery CIP spec.

When I tried the ammo for the CZ .505 Gibbs that CZ was selling to go with their rifle,
it was CZ-branded ammo, but was loaded by the now defunct A-Square Co.
I could not chamber a single round of it.
I got Jamison brass and used that, just fine.

It might happen that an ammo maker screws up the brass specs on small batch stuff like 500 Jeffery or .505 Gibbs.

The CZ rifle and the A-Square-made ammo were supposed to be compatible, marketed together from the get-go, following the same chamber design, on the same page, etc., but they were not.

I think CZ dropped that ammo line like a hot potato and refused to give any refunds to those that wanted to return it.
I was in the first batch of CZ .505 Gibbs rifle buyers, way back when.
Things got sorted out by trial and error, eventually.

If I may interject:

The CZ in 500 Jeffery is not a CIP regulated chambering but a product of CZ USA. If it were made in the Chech Republic they would be forced by law to cut the chamber to the CIP spec.

This means that CZ USA more than likely uses a non CIP chamber cutting die and thus it does not conform to the Kynoch ammo which incidentally is CIP regulated. In fact this ammo was the very first CIP regulated offering in this chambering.
There are no examples of 500 Jeffery ammo made originally by Kynoch. No examples exist only a drawing.

The original 500 Jeffery rifles were sold with Gecado ammo which was in fact 500 Schuler ammo
The cartridge dimensions of the original Gecado ammo was not the same as the chamber casting of the original 500 Jeffery rifles

The problem with the "modern " 500 Jeffery is that a number of dimensions existed prior to registration with CIP, various cutting dies of differing dimension existed prior to the acceptance of the drawings based on a original Kynoch drawing that was on file at the Birmingham Proof house.

This problem is not uncommon at all especially in the custom gun trade where different gunmakers were using non CIP spec cutting dies and calling it a 500 Jeffery.

So a call to CZ-USA to ask for their reamer specs might be one avenue of investigation.


Alf may well have the answer there.
Here is what A-Square was using for 500 Jeffery in 1996, posted on that 2010 thread also:

A-Square had something in 1996 similar to the Romey "Hybrid" of 1997?

Thank you ,i receive the answer of my question .

I use the Romey Hybrid in my rifle and have no problem to reload this cartridge with RCBS dies !

It does seem crazy that CZ-USA would use anything but a bona fide C.I.P. 500 Jeffery reamer,
if they called it a "500 Jeffery."
That was the existing standard when they made it, well known and widely accepted.

interesting, here is a what maybe a red herring. but I have a custome 500 Jeffery I had built and after firing the ammo I have fonf trying to reload the cases in the same die set that I crush a number of cases?? any ideas?

This is exactly why there is a standardization standard such as CIP.
The Germans and British gun trade went through this many years ago ( at different times) when they " normalized" cartridge and chamber dimensions. CIP normalizes dimensions for cartridge and chamber form as a matter of law for those countries who are signatories.

The 500 Jeffery in "CIP" form is a relatively new / recent development. Prior to this there were any number of dies and dimensions out there. Reloading dies also do not match the chamber form.

Now here is the kicker. The chamber dimension of the original 24 Rifles made by Mauser and finished by Leonard for Jeffery ( 21) and Gibbs
(3) do not match the dimension of the Original Kynoch drawing ( now the CIP spec) It does chamber and shoot Kynoch ammo as well as my own reloads using RCBS dies

We should ask Jason Morton at the CZ Custom Shop or Harlan at Triple River. I can do that unless someone else wants to

I asked Harlan the question, I'll either know more or be more confused in a few days. I'll post his response.

Harlan responded to my question today:

From: Harlan Satrang [mailto:tripleriver@embarqmail.com]
Sent: Monday, November 03, 2014 6:31 AM
To: Chuck Scappaticci
Subject: Re: CZ 500 Jeffery CIP, Schuler or ?

the reamers we us are from Pacific Tool and Gauge, which are made to the latest CIP drawings available. there is some ammo out there that is not compatible. hopefully everyone will get on the same page soon. one of the problems is that there are at least 3 different drawings out there.older than the one we used.
Harlan
----- Original Message -----
From: Chuck Scappaticci
To: info@tripleriver.net
Sent: Sunday, November 02, 2014 3:33 PM
Subject: CZ 500 Jeffery CIP, Schuler or ?

Hi Harlan, a question came up on the Accurate Reloading Forums and I thought I would ask you. I have a 500 Jeffery you built me and I’m very very happy with it. The question was: Is the CZ Safari Classic in 500 Jeffery chambered to the CIP standard? I know Kynoch factory ammo wouldn’t chamber in mine, but Jamison 500 Jeffery brass slid in like butter.

Hope you are well,

Thanks!

Chuck