The next step after sizing or resizing the cartridge case is priming. Every loading press has some way to prime the case. I know we're trying to pinch pennies here but forget that. The loading press has far too much leverage for the job, so much so that we can't feel the primer bottom out. Anyhow, unless one buys the automatic primer feed, priming on the press is just way too slow. If we want to buy the auto primer feed we might as well buy the hand tool. RCBS and Lee each make one. I prefer, in this case, the RCBS. The Lee is actually a bit faster but the pot metal lever tends to break after five or ten thousand rounds. That's okay for the box of shells a month shooter, maybe, but not for the guy, or gal, running through a thousand or more rounds per week. Whichever priming tool you choose, read the directions. Three times.
The RCBS hand priming tool has another feature I like, a steel stamping that keeps the primers in the tray from contact with the primer being seated. In the forty-five plus years I've been rolling my own I've only had about three or four primers pop while being seated. Still, that tray holds a whole box of one hundred primers, the detonation of one could cause more to pop off. One primer going off didn't ever hurt me, a hundred at once? That would cause damage. Now is a good time to put this in...Pardon the raised voice. ALWAYS, ALWAYS WEAR SOME GOOD EYE PROTECTION WHEN PRIMING CARTRIDGE CASES!!! As a matter of fact, wear eye protection when engaged in anything to do with shooting or handloading. Even something as mundane as getting clean cases out of the tumbler. I once spent an hour with an eyewash thing getting a piece of ground walnut shell out of an eye, I was shaking the tumbling media out of a case just a bit too vigorously. This was before these durned bifocals. Think I'm woofin' about eye protection while doing anything shooting related? Try getting a drop or so of bore solvent in an eye while cleaning your shootin' iron. If we have enough solvent in the bore to do any good it will spray when the brush exits the bore. That stuff smarts.
Okay. I haven't yet mentioned this in this series so now I will. Every time you go to the range, scrounge around for those plastic inserts they put in the cartridge boxes of factory ammo. There's no such thing as too many of them. They're useful in holding the brass in between stages of loading it. I have some eight or ten thousand .357 and .38 Special cases, every one that isn't loaded is either in those inserts or those coffee cans with plastic lids. I've only been shooting and loading the .45 Colt cartridge for about eight months, I only have 750 or so of those. They too are in those 'blocks' and coffee cans. Don't drink coffee? Buy some Tupperware, or the supermarket equivalent.
Okay, ready to prime some cases? Clean off a space on your bench. Set a box of cartridges in that plastic block down. Lay the tray from your priming tool down and take the clear top off your box of one hundred primers and lay it over the tray. Now slide the box out of it's cardboard sleeve, slow and easy. The primers are in ten rows of ten. You'll feel and hear each row drop onto the tray. If you're only priming one box of fifty (or twenty for that matter) drop only fifty primers.(or twenty). Now, close that box up if there are primers left, if you're priming a hundred, throw it away. All of the primers must be anvil up on the tray. They won't start that way. Shake the tray gently, in a circular motion. Gently, we don't want primers flyin' all over Hell's half acre. See those circular grooves on the tray? The feet of the anvils catch in those grooves and flip the primer over. Once I'm down to the last two or three upside down primers I usually give up and flip the last couple by hand. Make sure your fingers are clean and dry before touching the primer. Before we put the clear cover back on and insert the tray into the body of the tool, take a primer and give it a close look. See how the feet of the anvil stick out past the cup a tiny bit? A primer isn't fully seated until those feet are flush with the cup. Don't worry, you'll feel it when it happens.
Note: In the old days the slightest bit of sweat, skin oil or case lube could kill a primer. Primer sealants have improved a lot over the last few decades but it's still best to handle those primers as little as possible.
Okay, we're almost ready...before starting did we scrape out the thick carbon from the primer pockets? If we have a case tumbler, look to see if there's any tumbling media stuck in a flash hole. Last chance to get it right. Take that block of cartridge cases, put one hand, or a piece of cardboard over the cartridges and flip it over on the bench. Slide your hand or cardboard out from under and now lift the block off. Most of the cases will be standing base down. Don't worry if some fall over, it doesn't hurt anything, just slows us down a tad. Lay the block back down next to the cases. As we load a few boxes we'll adjust the placement for speed and to minimize fatigue. Now, pick up the priming tool in your strong hand, a cartridge case in your left. Slide the case into the shell holder and squeeze the handle. You'll feel the primer start into the primer pocket, then as those feet bottom out, you'll feel a slight increase in the resistance as we push the lever through to the stop. Voila! A primed case. Put it in the plastic block. As we develop a rhythm our speed increases. Don't force the speed, it will come. As you prime, work on eliminating wasted motion. I pick up a case in my left hand, slide it into the shell holder, and, unless it's a real short case like the 9mm Lugar, never turn loose, I seat the primer, slide the case out, put it in the block and pick up another case on the return trip. Starting from scratch I can prime a hundred cases in less than five minutes.
Note. Do NOT have the mouth of the case pointing at your face while seating a primer. Don't have your finger over the mouth of the case, either. It's real rare to have a primer pop, it's not unheard of. That primer flame is hot enough to give a real owie. It won't kill us, but there is enough unavoidable pain in life already.
Until we're experienced in seating primers, there is one more step. Lay a piece of glass like a hand mirror down and set those primed cases mouth up and give the mirror a little shake. Just do a few at a time at first so you can see if they wobble. Any case that wobbles has a high primer. High primers are a Bad Thing. They cause misfires and unintended Loud Noises. They can cause a KABOOM! That primer should be about two thou below flush with the casehead.Any cases that wobble should go back into the shellholder and get scooched down where they belong. Take your time with this, after a thousand or so, you'll develop such a feel for the operation that you'll be able to omit the step. If it feels funny when I seat a primer I set that case aside, when I finish the box, I give it a close look. Anything wrong I fix it then.
Remember, don't hurry. Speed comes with rhythm and eliminating wasted motion.
There are several brands of each size of primer. There are also Match Primers available. They vary as to each manufacturer's idea of the 'best' cup hardness and tiny variants in the priming compound. There is often a noticeable difference in pressure, velocity and accuracy found when we switch primers. I own one revolver that misfires when using CCI primers, their cups seem to be harder than the Winchester and Federal primers I use instead. I just avoid buying small pistol primers in the CCI brand, that way I don't have to worry.
Unless your load is already at max pressure, we don't really have to worry about switching primers. If we're at the red line then back off on the powder charge a little before experimenting. This is true of any change in components. We can always work back up. Rule of thumb: Changing primers will not make a horribly inaccurate load good. Changing primers can make a good load better.
As we load, fire and reload our cartridge cases the primer pockets will eventually loosen. The higher the pressure, the faster this happens. At the very max pressure a primer pocket will start getting loose after only two or three firings. There is no reason to run those kind of pressures my loading, if I can't get at least six loads out of a case before the primer pocket loosens, I back the charge down a little until I can. I've done a lot of chronograph testing and there is little velocity gain in the two times before they're loose and the six time loads. Since ninety percent of my handloading is for putting holes in a paper target, I tend to use new cases for max loads, only using them once or twice more at that level before I relegate them to easy shootin' mild loads. There's no reason to load max loads all the time, just like we don't drive a hundred miles an hour to go grocery shopping. Not one shooter in a hundred owns a chronograph, not one chronograph owner in a hundred owns an Oehler Model 43 Personal Ballistics Laboratory. Google that, check the price and see why. Us po' folks have to rely on case life to tell when pressures are getting too high. Don't go 'round eating up your safety margin for no good reason.