All my past and present 9,3x74r drillings have had steel frames, so I can't comment first hand. I have used a friends Kreighoff a few times, and he has been shooting it for four years...still tight as a drum. He also uses heavy 12 ga loads in it.

One thing to remember about drillings is that they are trimmed down to the limits to keep wright down and aren't made for every day field use as a shotgun. They tend to loosen up a bit quicker than a DR or a SXS shotgun with hard use.

I have a nice pre war H. Triebel-Augsburg dural frame drilling in 16 & 8x57JR that I use as a field SXS for chucker hunting, because its one of those guns that just seems to fit right and point itself, but I use only light loads to help keep it tight.

I recently sold a very nice little Eduard Kettner in 16 & 8x57JRS made in 1938 that looked almost new. It weighed 6 lb, 3 oz with its light dural frame. It was one of the nicest drillings I've owned, but it shot loose in a hurry.

This being said, I have heard from those who should know that the new Kreighoffs hold together well with the dural frames. Just use common sense, and one should make you a lifetime gun. Also, the later post war guns seem to be heavier and stronger than the pre war counterparts; the new ones are designed for hide use and don't need to be light.