We can't keep .357 rifles on the shelf at our store, but we get the horror stories from customers where they tried to cycle .38's through them and they locked up. It ain't rocket science to see the case length differences between .357's and .38 cartridges, so figuring out that short cases won't cycle cleanly shouldn't come as a surprise.
It's seldom we get any problems when the gun owner uses .357 magnum cartridges, but when they go "on the cheap" and start pumping .38's through them, the guns simply lock up. We get a lot of EMF and Marlin rifles through our shop, with few complaints regarding "feeding problems", primarily because when we sell them, we take particular care to tell the new owner to use only the ammunition called for by the manufacturer. We've had several of the new Ruger bolt guns in .357 lately, and so far as I know, without any complaints.
I bought a .44 Magnum lever gun to carry along with my old Herter's .44 Single action, so I like the pistol caliber rifles... but if I loaded .44 Special cartridges for use in the rifle, I'd make sure they had the same overall length of the .44 magnums. That way, the gun is tricked into thinking the ammo is just what it's designed for... silly rabbit....
Anyway, the problems we hear about are when the cartridge lengths are different... and those seem to be very consistent complaints... feeding problems. Then again, we get some customers who apparently can feed anything through their rifles and it seems to work.
WT