Larry,
Most will tell you that it is just easier to bugger up the process of a falling block than a bolt gun. I have built quite a few of both and the bolt will go past the falling block when it comes to hanging up after a stout load. But frankly, I am past either one becoming a problem. A sticky drop or sticky bolt handle is not in my cards.....
Oh, probably the nastiest falling block ever built was the 8mm Panzerbüchse built by the Germans. The round was based on a 20mm case necked down to 8mm. A bad, bad boy indeed.
Hey GOB, most of us nuts do stuff cause we can or it's there or a combination of the two.
I sure was looking for the penetration test data I found on the neta couple of years back. But alas, the page is gone. I found the listing but nada when you click on it. The old 45-70 was first or second as I recall. The hard cast 400 or 500 is just so tough and does not do anything but plow.
Best,
Ed