rhyrlik

Power Pistol was designed for 9mm NATO. It is stupid proof.

They don't have to pass the plunk test. Cast bullets are going to fit tighter in the chamber because they are sized larger and are covered with lube. Some will have splotches of lube on the nose that will interfere with plunking. The force of the slide slamming into battery will overcome these minor fit issues. As was suggested, determine max OAL with dummy rounds and work up a load.

.374" is too much crimp, but not all that excessive. I set mine to .375", but measure some Win factory ammo. Talk about over crimping! Something else is going on. Are you seating them straight? Are they bulged on one side of the case? Or is the bulge nice and even all the way around? If they are seating crooked, that could explain why some are sticky.

More likely an overcharge of a fast powder under a heavy bullet, like Clays under a 147. When you use a large flake powder in a powder measure, due to the way it meters, some charges are going to be too light and some too heavy. Most are going to be just right. That's why it is better to meter by weight rather than volume whenever you are playing with a sensitive combination of components.

"Some guys just want to shoot and not deal with the hassle of paying strict attention to details when loading ammo." Those people should not reload.

"May I ask how do figure over 50,000 psi?" By the fact his primers are falling out.

Primers falling out means the casehead expanded and it has nothing to do with the firing pin or soft primers. Old, pre-"dot FC dot" brass is soft. Use newer FC or Win brass as it is hader and stands up better to pressure. You do realize you're running close to 50,000 PSI, don't you?

If your throats are .358" then you should lengthen the freebore. Get a reamer and do it yourself.

Right. An easy way to measure the throat is to take a bullet and smack it with a hammer to increase the diameter, then load it in a case, and hammer it into the chamber. The throat will reduce the diameter of the part of the shank sticking out the case mouth which you can then measure. I like to size .0005" under throat diameter. That allows easy chambering with good obturation and no leading. If your throat is .357" then using .357" bullets will result in difficult chambering. You have to allow for a little clearance. You may have to run them through a .356" sizer which will create a .3565" bullet due to alloy spring back. Only then can you establish OAL with a plunk test.

Is the bullet being engraved by the lands or by the freebore?

You need to determine throat length and diameter, then size the bullets appropriately. Then they will pass the plunk test.

FC factory 9mm is loaded with magnum primers. Usem.

The KKM 9mm chamber is very generous. Mine accepts .359" 38/357 bullets and actually needs that size to prevent leading. I normally use 125gr TC FP .359" bullets on top of 3.5grs of bullseye @ 1.040" OAL.

Universal Clays typically gives large ES in the 45 ACP. Bullseye gives 20 FPS ES at the same velocity. Try 4.6grs of Bullseye.

"Only leading i've ever had was with a batch of too soft bullets that I cast with the wrong alloy." Too soft for the 45 ACP? What is the minimum hardness for the 45 ACP?