Unless you are regularly shooting large quantities of ammo, e.g. gallery rifle or pistol competitions, there is little point in choosing an indexing or full progressive press.
An excellent post by Sharpie. I'll add my tuppence worth, more like sixpence worth, as we go.
Since you are interested in accuracy, you should be considering loading as a batch process, rather than continuous.
An indexing or even progressive press seems attractive because you can produce one complete round at a time, with only a few pulls of the lever, but you are sacrificing the ability to modify your workflow or inspect the results at each stage. You will also be relying on an automatic powder thrower, rather than individually weighed charges. You will not be cleaning primer pockets or trimming to length. You will not be inspecting the results of each intermediate process. You can also rapidly manufacture lots of junk if something goes wrong with the setup.
I have a Dillion press. I currently use it for loading .38 Special, I might use it for .303 (neck resizing only with dry lube). I inspect each case as it goes into the press and when it comes out of the press as a loaded round. In theory, you could produce 400 rounds an hour with this press. In practice, the inspection stages reduces the rate.
Powder measuring. Why does anyone weigh powder charges? If your powder measure delivers charges that are +/ 0.1 grain that's good enough. There are other variables which have much greater effect than powder charge, e.g. bullet seating depth, so weighing charges is a complete waste of time in my opinion. I have a Redding powder measure which generally is within 0.1gr of the intended charge. To my surprise, the powder measure on my Dillon is almost as good (I weighed over 100 consecutive charges when I first got the machine). My standard .38 Spl load is 4.2 grains of powder.
I load 50 or 100 rounds at a time, batch mode.
My precision workflow for rifle calibres is:
Fit universal decapping die (precise adjustment unnecessary). Decap.
Scrape out primer pockets.
I also use a Universal Decapping Die, very handy thing. But, if I'm to tumble the cases I leave the primers in situ. Tumbling media can find its way into the flash hole and the Universal Decapping Die will remove it on decapping. You don't want to have to spend you time inspecting each flash hole and poking out pieces of media. (I use crushed walnut shell.)
Primer pockets. I use either the Sinclair Primer Pocket Uniformer (a small reamer which squares off the primer pocket and cuts it to a uniform depth) or latterly the Forster primer pocket cleaner. I have a Forster case trimmer and the primer pocket cleaner fits into the head of the trimmer shaft. It's fast to use. With the Sinclair, I use a small battery screwdriver to power the primer pocket uniformer. I hold the screwdrive in one hand and the case to be cleaned in my other hand. In both cases, it's faster than a hand powered tool and does a better job. It also prevents RSI to the wrist.
Inspect for e.g. splits, head separation etc.
Wipe off lube and inspect.
Measure OAL with calipers. If beyond limit, trim with Lee case length gauge/cutter and apply light internal chamfer.
Inspection is a crucial step. Earlier this year, a shooter next to me had two case consecutive head separations (the cartridge case body was left in the chamber and the case head extracted by the bolt) in a war production .303 No 4. He had reloaded this brass twice (i.e. this was the third firing). He had never inspected the inside of the case for incipient case head separation. (He had not head of it. If you don't know what it is, look in any decent reloading manual or google it).
The RCBS Case Master is a versatile tool for checking your brass. It has a sharp probe that will tell you whether your cases are thinning and you have incipient case head separation. You can also measure the length of you cases in second (i.e. whether they need trimming). If you are so inclined, you can also measure the neck run out (how concentric) your cases are and case wall thickness. It's a piece of kit worth having but not essential.
Resizing a case causes it to become longer. It is essential to verify that the resized cartridge case does not exceed specified maximum length. You could measure each case with a dial calliper but that's time consuming. The RCBS Case Master is faster. But I tend not to measure the brass, instead I simply put it through a case trimmer. I have the Forster case trimmer to which I fit the 3-in-1 cutter. This is a device that, as it's name implies, does three operations in one - so saves you time. It trims the case to length, and deburrs the inside and outside. You only have to handle the case once, not three times. The Forster 3-in-1 cutter isn't cheap, but it is an excellent piece of kit and it saves a
lot of time. It's fast and it produces an excellent finish. So I don't bother measuring resized cases, I simply put them through the case trimmer: if they are already below specified length, no material is removed. Otherwise, a few turns of the handle (or a push of the power screwdriver button) has them done in seconds and I have to handle each case once only.
I also have the RCBS Trim-Pro case cutter with the RCBS 30-in-1 cutter. It does the same job as the Forster 3-in-1 but you have to set it up and it's quite fiddly. (You have to adjust the cutter that deburrs the outside of the case.) Once set up, it should not need further adjustment. I have found that it can produce a satisfactory result but I have also had problems with the outside cutter 'wandering'. So you end up checking eash case, and that's time consuming. Due to this, I recently bought the Forster 3-in-1 cutter (I already had the basic case trimmer body etc). The Forster 3-in-1 cutter is set up at the factory so you simply fit it to the trimmer and start trimming, no messing about. (You will need the longer trimmer stand/body if trimming .30-06 length or longer cases since the 3-in-1 cutter effectively shortens the length of the shaft reach. But the body isn't expensive and to change them is dead simple.)
Since the RCBS and Forster cutter heads are about the same price - give or take a few quid - I strongly recommend the Forster over the RCBS. Forster make .224, .243, .264, .284 and .308 cutters. RCBS make a wider range of cutters. I'm in discussion with RCBS about the design of their cutter and I am to take some close up photographs of the cutter head in question to illustrate the problem to them.
-JMS