Anyone using Kynoch Factory 500 Jeffery (CIP) ammo in their CZ 550 Safari Classic 500 Jeffery's? I bought a 5 pack and it won't feed from the magazine or extract if I single feed it. It's probably my rifle (which I will have to send back to Triple River Gunsmithing) but if it's the ammo I would like to know.

Regards,

Chuck

NEW kynock is bertram brass
call triple river and ask them what they used to verify feeding and which chamber.

quote:

... but if it's the ammo I would like to know.

I know the 500 Jeffery was known for feeding problems, but shouldn't a rifle be able to feed any ammo you throw into it?

I believe that André, who posts here as JefferyDenmark, had a lot of trouble with .500 Jeffery caliber Kynoch ammo in his Heym rifle.

You could PM him for the details. Or a search may turn up the relevant threads.

Buy Norma African PH .500 Jeffery ammunition instead!

570 grain Woodleigh bullets

Hi Husky, the only reason I bought the Kynoch was it was in a 5 pack lol, and it said 500 Jeffery CIP. I can send it back to Midway. I just want to make sure the rifle funcitons (feeds/fires/extracts) normally with good factory ammo before I start load development. This will be the only factory ammo I ever buy for it, since both the Norma and Kynoch run $20 a cartridge!

I'm going to call Harlan at Triple River Gunsmithing today and see what ammo he tested it with.

Regards,

Chuck

Checked with Harlan, he used the new Jamision brass and Woodleigh solids to check feeding and extraction. He's sending me two dummy rounds. I measured the Kynoch compared to my Jamison brass and they're vey different. I sent the Kynoch ammo back to Midway. Hopefully all is well, I should know in a few days.

Thanks all,

Chuck

If you continue to have problems an option would be to send your fired cases from Harlan to RCBS for deminsion check.

Chuck, I thought for safety reasons ammo could not be returned?

I guess I'll find out. I sent it UPS ground with a return slip. If they won't take them back I'll offer them out free as display rounds for those on the forum that collect cartridges.

Chuck

Yeah, Sevens is correct. They don't accept returns on ammo. Damned shame, too. Kynoch is the most overpriced ammo on the market.

quote:

Originally posted by jetdrvr:
Yeah, Sevens is correct. They don't accept returns on ammo. Damned shame, too. Kynoch is the most overpriced ammo on the market.

guess that they have the same problem as most small manufactures...

no one mentioned noody forgotten

And that is QUALITY CONTROL!

Yeah, husky, but they're gonna stay small if they don't get those prices down at least 25%. I'd like to try some of their .458 and .375, but there's just too much good stuff out there cheaper.

jetdrvr,
Agree, They need an Investor that likes Big Bores!

I am in the process of order some Kynoch 450/400 3 1/4" N.E. ammunition..

I have a 500 Jeff Heym rifle...circa 2008...and it feeds and fires Kynoch perfectly. The CZ's have had some trouble with chambers and feeding issues. Get some NEW Jamison brass and try it out. The Jamison and Kynoch brass are similar, but not identical.

Gary
DRSS
NRA Lifer
SCI
DSC

Thanks Gary, I have some new Jamison brass and it was substantially differentfrom the Kynoch ammo. The shoulder angle was very different. I plan to try the Jamison brass out, unfortunately I'm still working on getting my press in shape even though I have the dies.

Chuck

The .500 Jeffery was an original design by the German firm Schuler. I believe it was Kreighoff-Schuler or vice-versa. The Schuler design is known as the 12.5x70 Schuler (.500 bore UK land to land), the 12.7x70 Schuler (.510 caliber grove to grove), the .500 Schuler, and the .500 Schuler Jumbo. The .500 Jeffery has a 12.61 degree shoulder angle and an 8.33 mm neck length. The .500 Schuler has a 19.9 degree shoulder angle and an 8.70 mm neck length. They are not interchangeable. Source of this data is Dr. Ron Berry reaseach effort.

The cases will look different.

Thanks Buliwyf, the Jamison brass has a a more gently sloping shoulder, I didn't measure it, so I'm assuming the Kynoch ammo is 500 Schuler.

Chuck

You are welcome Chuck. The .500 Jeffery/.500 Schuler is worth every bit of trouble you are going thru at the moment. It is an incredible cartridge!

The following is Dr. Berry's original research that I am aware of:

For both cartridges, the simultaneous May 15, 2002 CIP maximum brass specs, of course, and all I did was some arithmetic and converted the minutes and seconds of angle to degrees, for fun:

Max brass length:

12.7x70mm (500 Schuler) is exactly = 70.00 mm
500 Jeffery is exactly = 69.85 mm

Schuler neck length = 8.70 mm
Jeffery neck length = 8.33 mm

Shoulder semi-angles (max brass spec, not chamber mini spec, mind you)
Schuler = 19.9503056 degrees
Jeffery = 12.614028 degrees

Schuler: shoulder diameter = 15.32 mm, base diameter = 15.73 mm
Jeffery: shoulder diameter = 15.42 mm, base diameter = 15.72 mm

Schuler rim diameter = 14.65 mm
Jeffery Rim diameter = 14.61 mm

I still like the Schuler better. It has a longer neck and less rebate, more body taper, and a more positive shoulder.


"Rip" Ron "The Don" Berry



There is a "Jeffery," a "Schuler," and a "Romey Hybrid."

.500 Jeffery: Kynoch 1928 drawing shows 12.63-degree shoulder semi-angle.

12.7x70mm Schuler: RWS 1940 drawing shows 23.54-degree shoulder semi-angle.

.500 Jeffery: Romey 1997 drawing shows 19.97-degree "Hybrid" shoulder semi-angle.


Three different shoulders. Search for Alf's elucidations here, complete with drawings of the relationship of shoulder angles.

I do have the monograph on this, courtesy of Alf and his RSA Big Bore friends.

Dies should be made specific to the chamber being used. The same brass will work in all of them when properly formed.

The original 1928 500 Jeffery ammo will chamber in all three rifles.

The original Schuler ammo will not chamber in the other two, only works in the Schuler.

Draw those shoulder angles all terminating near the same point at neck-1 (shoulder-neck juncture), but widely divergent at beginning of shoulder: three different headspaces.

Where is that drawing? Search ...


"Rip" Ron "The Don" Berry

Buliwyf-
Thanks for the above- I haven't seen this info gathered together in one place before. This should be a sticky.

RG

You bet RG!

You can send fired cases to RCBS and those nice people will make you a perfect set of dies regardless of which chamber your rifle has. The .500 Schuler/Jeffery is a glorious round and well worth the effort. They feed as slick as you could ever want.

/

Hullo Alf,

Yes, without question, Col. Casey Lewis is one of the world's leading experts. I have talked with Casey by phone a few times and in fact have tried to assist him with his past research. The last time we talked would have been around 2005 I think.

Thank you for your post.

Buliwyf,
Good work in flushing Dr. Alf out of hiding.

Alf,
You did not give me that monograph, you sold it to me, and I thank you for that!

Yes thanks for all the great info!

Chuck

I got my dummy cartridges from Harlan. Jamison brass, Barned Banded 570g solids. They feed, chamber and extract fine. So I'm going to use them as my template for my handloads. If it feeds and extracts the Barnes solids, it should be awesome with Woodleighs.

Thanks all, I'll post a range report in a bit once my press is all set up and I can make it to the range.



Chuck