I've had some issues with my Redhawk 5032 that resulted in Ruger swapping my original out of spec revolver for a new one. The new one was significantly better, but was not quite 100% reliable in double action. I think I've got it resolved.
The first thing I did was tear the revolver down and inspect the innards. There were no obvious burrs or major issues, but I did notice it was completely dry. I lubed all contact points and reassembled. The second thing I did was stone the hammer a bit where the hammer hits the frame. There were machine marks on it, almost like a finger print but more regular, and it did not appear to be hitting exactly flush. I stoned it down smooth, taking maybe a few hundredths of an inch of metal.
The result was a significant improvement in reliability. Using Starline brass, CCI primers, and 6.6 grains of Titegroup under a 230 gr plated bullet, I loaded up 40 test cartridges of .45 Colt. I also took a box of factory HST .45 ACP hollowpoints. All cartridges fired. All HSTs were shot double action, 34/40 of the handloads were shot double action. The HST did occasionally result in my face being pelted with debris. I'm not sure if it's shaving the bullet a bit or I'm just getting blow back. I was on an indoor range and unable to recover bullets. None of the handloads caused the issue. Accuracy was within acceptable limits given my skill level.
Handloads at 7y, 1 called flier, double action.
Speeding up a bit, 34 shots into upper box. 6 shots of slow fire in the circle (the first two were center and slightly to my right, as I went along I pushed a bit high) and the final 4 cartridges in the 1" square were shot single action. I heeled the first shot bad and it's the highest one. Took my time and got it down into the box. The load shoots POA when I do my part. I find the round butt a bit more difficult than a square butt and suspect I'm heeling the gun a little bit.
This is 18 shots of HST, all double action, in strings of 6. Shoot 6, drop the moon clip, reload and get right into the next 6.
I don't have any S&B primed cartridges at the moment to see if it will now pop harder primers, but initial results look good for CCI primers and domestic ammunition. This isn't a high volume revolver for me, but I still intend to load up some of the cheaper primers and see how they do.