Well, actually, I will add a word. Using RCBS carbide 3 die set, adjust your resizing die by screwing it in until it almost touches the case holder. Best done by gently screwing it in until it touches, and then backing it out a quarter or half turn.
Adjust the belling die by screwing the die in 'til it touches the shell holder, lock it in place and back out the flaring tool. Place deprimed resized case in shell holder, and raise it fully. Then screw in flaring tool until it touches the case mouth. Take case out and examine for flare. Keep turning the flaring tool into the locked die, and raising the case until the die body touches the shell holder, and testing for enough flare to set the bullet without it catching on the case mouth. All words of wisdom say "just enough, but not too much.' Precise, eh? Like was said, too much causes premature case mouth cracking, too little makes for off center bullet seating, or crushed case mouths. More for cast bullets, more for flat base bullets, less for jacketed and less for bevelled bases.
Then, when seating the bullet, again, thread the seating die into the loading tool until it is a couple of turns short of touching the shell holder. Back the bullet seating punch our, set bullet in flared (and primed and charged) case mouth, raise the ram, and thread bullet punch into seating die until resistance is felt. Lower the ram, turn the seating punch in a few turns - 1/32 in for each turn, I believe, but work slowly, to ensure you don't seat too deeply. Once the bullet is seated to the desired depth, (the case mouth should fall in the upper portion of a cannelure or crimping groove) back the seating punch out a few turns, and start turning the entire seating die into the press, raising the seated bullet and case each time, until you feel resistance. You are setting the roll crimp with this, so take the loaded round out, examine the crimp - best to compare with a factory load - and when you have all the crimp you want, lock the die. Turn the seating punch down onto the seated bullet and y voila, you have bullet seating and crimp all in one for a .45 Colt.
Sometimes you will have to fine tune things a bit, as bullets have minor variations, and if you set up on a case differing in length from the usual, your crimp will need tweaking, but with revolver ammo, there is no reason you can't seat and roll crimp in one stroke of the ram.
.45 Colt likes a stout crimp, especially if you are loading stout loads - and on CGN, I seldom see anyone wanting anything less! Even on middling loads, a good crimp favors accuracy, as it leads to consistent bullet pull, while shooting through what are in effect, six different firearms.
The little instruction pamphlet with the dies explains all this, but it is best done step by step, rather than trying to assimilate it all in one read. I figured it out years ago just from trial and error, and didn't hurt anyone! I crushed a few case mouths from catching bullet bases on insufficiently flared case mouths, and yup, I've got primers in backwards and sideways, and bullets seated so deep my recoil got unpleasant - Lee bullet lube buildup in the seating punch - but all is well, that's how we learn. Contrary to what some CFSC instructors would have you believe, handloading is not the same as making terrorist devices in our homes!