All~ I recently acquired a Swiss Martini-Hammerli 3-position rifle dated around 1920. 

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The rifle is proofed for the GP11 ammunition, with a groove diameter of .307" and finally a full set of sights (bought Schützen sights because a base was added to the rifle, although I'll use the barrel-mounted rear sight assembly as they did in the original 300m competitions). 

I have never engaged in this discipline, and I confess my ignorance about how to handload for this type of rifle. I would appreciate it if someone were to walk me through what I should do. For instance: 

1 - Should I paper patch, and if so, at what diameter and why?
2 - Can I get away with a bit of trial and error without doing a chamber casting?
3 - What would be the drawback of using cast lead gas-check bullets? 
4 - Anything else I should know, or a good resource (even in French, Italian or German) anyone could point me to? 

Thanks a lot in advance--I want to make sure I get this right without messing up the rifle, which has an absolutely perfect bore. 

Tom

Thanks, Dave--I've been a member of that forum for over 10 years... I find it amazing for military-rifle and militaria info, but less so for highly technical non-military shooting. That's why the "Other Swiss Arms" forum is quite slow compared to the other ones. 

Anyone in the know there will be a member here, but not the other way around...