dwarven1 said:
I have a friend with a 1905 Mannlicher. Uses Mannlicher 7.63x21 ammo, with an 85 gr bullet at 1000 fps.
Now, since we know the dimensions of the cartridge, weight of the bullet and the speed of the bullet... how does one go about reverse-engineering the load?
Actually basic data can be found in a few books, Cartridge Conversions being one of them. And yes, they have the 7.63x21 Mannlicher listed.
dwarven1 said:
Are there tables or equations from the powder manufacturers relating charge weight, bullet weight and bullet velocity? Does a commercial reloader (like your dad, Nickle) use a pressure test barrel on the new loads first?
Just wondering.
Most small commercial reloaders/manufacturers don't have test barrels.
The most important thing for a reloader to have is a good library. The bullet companies, reloading equipment compaines and powder companies publish loading manuals, some go into great detail, some don't.
Advanced reloading should only be done by an experienced reloader, and only in strong firearms. Advanced reloading entails watching the signs of pressure when making up new loads. It's something you learn over time, and can be difficult to explain.
I've been making my own ammo for almost 40 years (I obviously started young), and have been involved in my father's business for many years. I still rely on manuals, and pay strict attention to their max loads, and work up to them SLOWLY, watching for pressure signs.
Ross, let your friend know that my father's rules on ammo are simple.
First priority is safety. It has to be safe.
Second priority is function, the gun must function. If this can;t be done safely, then you either live with less function, or don't shoot the gun.
Third is accuracy, and this falls under nice to have. If it can be made accurate, great. The first two priorities take precendence over accuracy.
The reason my father needed the gun in the case of the 7.63x21 was to make sure the ammo fit and functioned. He doesn't make hot loads for anybody, not even me. And the ammo he sells he openly says is on the light side a little. This actually helps accuracy, in most cases. There's only a couple of calibers that actually like max loads.