doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com .500 ?

Thank you Raimey for posting my pictures and guys for the interesting conversations.

I have cerrosafe on order to do a chamber cast. I slugged the barrels 6" down on the breech end and 2" down from the muzzle. Both areas mike at .510 groove dia. It's hard to measure the lands being an odd number and narrow. The best I can mike the length on the chamber to the first step is around 2.100" with touching the rifling at 3.100" Unsteady hands and bad eyes now. Hopefully a chamber cast will help

Sounds right, if you have access to gage pins the getting the land diameter becomes easier.
Steve

I had access to pin gauges before I retired. I worked in an automotive stamping facilities. Team leader in Maintenance. They had a very nice tool and die dept.

Shortgrub,
You can get a pretty good approximation of the groove diameter from the chamber cast, or a lead slug driven into the barrel, with a digital caliper by lightly closing it on the slug, then "rolling" the slug until it "clears" and check that reading. You should do it a few times until there is a consistent reading. A friend of mine wraps the slug with a piece of his thinnest shim stock and mikes across the diameter. He then subtracts twice the shim stock thickness for another way of approximating the diameter. If you had access to pin gages, they may have also had ring gages to match.
Mike

Shortgrub;

The conversations here are of some interest to you I am certain. However, I suggest that you to to the acknowledged world expert of British double rifles, Graeme Wright of Australia. You can contact him at his email address:
thepilotgw@hotmail.com

I have always had very quick responses back from him when I have emailed him in the past. Send him an email and photos requesting the information you want.

Graeme Wright's book on the British Double Rifle will be of much value to you and I suggest you buy it. On page 70 (3rd edition) is information that I call you attention to where he states that by in large all original British black power rifle cartridges were paper patched; and further he states in regard to the .500 black Power express cartridges: "In looking at the .500 black power express, the British standard size are .502" bore and .510" groove diameters. The original projectiles that I have measured were .502" for the projectile and .508" to .512" with the paper patch in place."

I think that your measurements indicate the above information from Graeme Wright is consistent with your double rifle's chamber dimensions.

I know that copies of Mr. Wright's book are difficult to find and are costly, and if you would like for me to send you copies of pages from his book concerning your rifle caliber, please send me a PM with your email address and I will send them to you.

Kindest Regards;
Stephen Howell

Well gents, I need new glasses. I cast the chamber today and found it to be a bottleneck case. 577/500 No. 2 I'm pretty sure.

Chamber cast trumps pics on the internet anyday, that is a great cartridge. Enjoy it!

Stephen,
I understand a 4th edition of Mr. Wright's book is currently underway, how far off I do not know. Best regards,
Steve

I certainly will enjoy it after I find dies, a bigger press, brass and bullets. Got everything else needed. Any suggestions?

Join

http://forums.accuratereloading.com/eve/forums

and

http://forums.nitroexpress.com/ubbthreads.php


Post a Want to Buy add in the classifieds of both and here at doublegunshop, watch ebay and gunbroker as well.

I just picked up 450 3&1/4" and 400/350 dies for very good prices.

Good luck.
Steve