Gentleman I created the 550 magnum first of all to be an easy conversion of a Cz 550 mag 416 rigby or simular rifle.
Next to be an affordable big bore. First I picked a brass source that would not have feeding or availability problems and tried to keep the cost down. It also must feed through a Cz 550 mag action or simular. I next decided to fill the gap between the .510 bore and the .585 bores. As a result the 550 magnum appears to have the capicity to compare with the 600 nitro express while keeping the beter penetration of the .510 cartridges.

458lott 500gr, 550mag 700gr, 550mag 800gr (Hawk), 600OK 900gr Bridger solid

Companies supporting this cartridge so far are

Barrels @ Cut Rifle/Wells Sport http://www.cutrifle.com/barrels.html

Bullets @ Hawk http://www.hawkbullets.com/
Bridger http://www.bridgerbullets.com/
GS Custom ( Said they would )

Head Stamped Brass @ Quality Cartridge http://www.owlnet.com/quality/

Loaded Ammo @ Quality Cartridge

Realoding Dies @ C&H Tool and Die http://www.ch4d.com/

Gunsmiths @ MICHAEL SCHEAR email @ gilagunwks@aol.com

Reamers @ Manson Reamers

We have 7 barrels right now for our inital order and would like to get a few more.

Here is a link which should answer most of the questions.

http://www.nookhill.com/ubb/ultimatebb.php?ubb=get_topic;f=16;t=004013

I can be reached at goldcoins1@aol.com

Thanks RNS