Andy,
Mate I would recommend doing bulk research. Research Fitting and machining, hand tools, carpentry, boilermaking, tech drawing, and everything in between. Write down your plans and ideas and review them constantly as you learn more. Live it, talk it, breathe it. Soak it up coz you'll need it all. It's a big learning curve but all you need to begin with is desire.
Get a torrent downloader and go to town collecting materials on how to build firearms, building custom bolt actions, gas operated sytems, lever systems, trade textbooks and so on for example ----> (
http://www.google.com.au/url?sa=t&rct=j ... 2246,d.dGY).
AGI have some videos on weapons systems and how they work.... Also, join a bunch of trade forums like practialmachinist, woodworking and metalsmithing forums. Surf catalogues and see what kind of tools and consumables are available and read about how people get around paying big bucks for jigs by building their own or inventing a new way to do things! --- Insert ppl like NoisyDad here --- Have an open mind and be flexible. You don't have to be a tradie to learn how to turn metals, it just helps if you have that background. Learn from those who do.
Anyway, I would recommend this lathe - minimum - to start doing your own work. It's an old workhorse, but very upgradeable and proven to do the job well time and time again. A bit more expensive and looks like it isn't any better but I think it is, that's just my opinion.
http://www.machineryhouse.com.au/L237 Spindle bore is 40mm, you can turn between centres as well if you prefer, or a bit of both... You don't need a foot brake, if you think about it you can design your own brake or add a VFD later on which can act as a brake. A good quality coolant pump is a more important upgrade than a brake IMO, get one with your lathe. Look for a second hand lathe if you want to save a bit of money, they pop up on gumtree regularly, and generally come with extra tooling and sometimes upgraded motors and rebuilt gearboxes etc. but make sure you have some way to move it! There are plenty of forum posts about this as well... Be prepared to learn how to strip and assemble your lathe to change gears, adjust gear tolerances as general maintenance! Ports can clog up and if you're lathe isn't oiling itself it will fail prematurely. Don't forget oils and lubricants
Tools can get expensive but if you focus on working the lathe and getting tools as you need them and not just generally it could work out a bit better. Watch for second hand stuff here too. Use HSS bits and learn to grind them to a fishtail gauge, although if you get carbides you save having to buy a bench grinder. But then again, a bench grinder can mount a linisher or buffing wheels for other works as well, you may want two.... You'll eventually have all of it if you want so it doesn't matter in the end. Lots of places to get good tools from; ebay is good, but MSCdirect is a good starting point for price comparison. I get lots of stuff off ebay, it's just so convenient. Ozmetool is a good aussie seller, mscdirect have their own ebay store, and you'll find more along the way as you research. There is about to be a big sale at Hare & Forbes from 20-22 Nov so you may save a few $$ if you're prepared to buy during these kind of sales. Get on the vip mailing lists of lots of toolshops here in aus, and overseas.
There aren't many places to get firearm reamers/gauges from around aus (if any?) but Pacific gauges and tooling are well known, Brownells, Clymer, etc. make high quality reamers and tools guaranteed to do the job.
Do loads of research before buying measuring gauges as you don't want to be buying these twice. This will kill you. Buy mitutoyo or starrett gear. Second hand isn't a problem coz it's lifetime guaranteed. Finger dial indicators, depth gauges, pin gauges, micrometers, verniers, etc. Learn to read and convert imperial measurements to metric and back again. Decide what your gauges will be, imperial or metric?
Anyway, you've got a mountain to climb :O get started or you won't get to the top eh?
Good luck.
HTH