Maybe think about the core processes and what you need for each.
- Choosing a load
For this you will need a reloading manual from a bullet manufacturer. The manual will also contain essential information on safety and technique.
- Case cleaning
This can be as simple as cleaning the primer pocket with a small scraper, but many people end up wet tumbling in steel pins to maintain a consistent case capacity and get new-looking cases every time. To start cheaper, ask any veteran reloader if they have vibratory tumbler they could spare. IYKYN.
- Case preparation
This involves de-priming (decapping"), resizing and trimming the cleaned case. You will need a set of dies for your chosen cartridge. The set will include a case holder that slots into the top of the ram in your press. Resizing dies incorporate a decapping rod. If you buy a separate universal decapping die, you can decap your cases before cleaning them, making subsequent resizing a cleaner process. Additionally, as brass migrates towards the case mouth over repeated firings, you will need a case trimmer (a kind of small hand lathe) and a chamfer/deburring tool to clean up the edge of the cartridge mouth after trimming. Alternatively, you can just discard a batch of cases when they exceed the "trim-to" length in the manual. This may cost you nothing more than an ethical twinge, as .243 is in such widespread use that you will probably know a non-reloader who will give you their once-fired cases. For sizing, you will need lubricant to prevent the case becoming stuck in the die, and of course a reloading press. A single-stage press is sufficient, but you will probably want to upgrade to a turret press as you seek to streamline your processes later. Resizing cases "works" the brass and makes it brittle, reducing case life, so many people use gas or induction annealing machines to heat the case necks/shoulder and restore its ductility and elasticity. Alternatively, discard a batch of brass once cracked necks occur and start afresh. Resizing is nothing without measurement, so you will need a reliable caliper tool. Finally, you will need a reloading block to stand your cases in between processes.
- Priming
This involves inserting ("seating") a suitable primer in the pocket in the base ("head") of the case. Most people use handheld tools, but several presses integrate priming systems.
- Charging
This involves measuring out the charge you have chosen and decanting it into the primed case. You will need a scale (beam or digital) and a powder measure. Scoops are the simplest/cheapest type of measure and quite adequate. A hopper-type thrower is faster and easier to fine tune. An automated combination thrower and scale is fastest. You will also need a funnel that fits over the mouth if the case.
- Bullet seating
This involves seating the bullet into the case mouth to a consistent depth. The die set you choose will include a seating die. Your calipers will be essential here, too. Hornady make a case comparator tool that lets you measure from the base of the cartridge case to the shoulder ("ogive") of the bullet - a more consistent distance than to the tip of the bullet.
- Load development
Now that you have your first loaded cartridges, you will have to test them for velocity and accuracy. This requires a chronograph as well as your usual range gear.
As you gain experience, you will identify scope for extending and improving your tools.
I am sure I've forgotten something here, but equally sure others will eagerly fill in the gaps.
Footnote/afterthought
A complete set of good reloading tools might cost you £2K. If you don't want to invest that heavily, used/old reloading gear is often available very cheaply through regional firearms auctions.
