Great stuff!

Recently I have had a long conversation about this topic with Dave Scovill of Wolfe Publishing. Interestingly, he has suggestions for mono bullet design that I think are worth repeating.

He suggests that mono's should have a diameter across the bands that goes .001 under groove depth and shaft diameters that are at least .004-TO-.006" UNDER LAND DIAMETER OF THE GUN IN WHICH THEY WILL BE FIRED.

His theory goes back to an issue discussed in this thread some pages back; namely, that monos do not obturate. I believe it was 400Nitroexpress who stated that at 38000 CUP or something like that a mono doesn't obturate. This is on the face of it, true, and accepted by all of us, except Dave says that the rearmost BULLET groove will, under the pressure of a shot fired with nitro powder, compress a bit. This may only occur in the one or two BULLET grooves closest to the base of the bullet, but such a collapse/compression is real, and it effects both pressure and barrel stress.

He points to engine pistons as examples. He says "seizure" of perfectly-fitting piston/cylinders can occur; under compression of firing, the piston may seize for a moment and apply immense stress to the cylinder.

I'm just passing this information on, as it seems the best explanation of how a "perfectly fitting" bullet could damage a barrel. I have no idea of the validity of the issue regarding protection from OSR. Scovill says ACCURACY will improve dramatically if his principles are applied to monos.

Seems about time I call Barnes and see how the experiments are going, too....