Cuddy; I've been loading for my two Ruger .44 Mags (Redhawk, and SBH) and an in-law's two Rugers (77-44 & an older .44 carbine) all-in-all, for over 30 yrs. Have run into the same problem as you have...more or less.
Try this: Take a virgin case, lube it and run it through the die as usual, to see if the hard sizing persists. If it doesn't, and it's easier with the new unfired case, then it's not the dies. I use [BAG BALM] for lubing all my cases--rifle and pistol-- whether I use carbide dies or reg. steel. Just a smidgen on the fingertip/thumb will lube 6-10 cases, and with a LEE C-Press, finger pressure is all I need; In fact- I have cut the handle/rod in half--[on an RCBS Partner Press] I use to resize all handgun and .223 brass...it's so easy, as the long throw was a hassle for me sometimes. Found a small golf ball-sized knob...drilled a hole to fit the unthreaded end and epoxied it on. However, I digress.
I keep my brass separated per the gun in which it's fired, and with the six-gun brass, I just resize the case far enough down the body to grab the heaviest bullet for that caliber, plus 1/8"+/-, and lock it down. It's full-length sizing for the semi(s), though.
Now...Before all you nay-sayers out there start trampling me....It has worked for me and for whomever else I loaded (until I stopped loading for others) with no problems....Period. Just keep the brass segregated per gun and you'll have no problems. The case CAN NOT get any larger than the chamber in which it's been fired, but if you'd feel better FL sizing after a few loadings...then go ahead. And don't you all laugh at the BAG BALM either; I've loaded over 6500 rds. from one 10oz. can, and you won't get any tarnishing/corrosion after storing for a long time as is possible with some water-based lubes...I know from experience.
Cuddy, I'm just offering something to consider. It won't hurt to give it some thought.... and IF it doesn't work for you, then at least you'll have a good salve for your rough hands. [That's how I got the notion to use the B B in the first place It's almost pure lanolin based. Good for leather too.
Hope you get everything straightened out.