<< Are the ballistics for the 45LC better than a .410 slug >>

Well... no, but that's not relevant. Darn good question, though!

Even with sissy factory loads, the 45 Colt is considerably more lethal than the lightweight .410 slug.

A Remington .410 slug is supposedly 1/5 oz - that's 87.5 grains - VERY lightweight (a little heavier than 2 each standard 22 lr bullets). It supposedly leaves the muzzle at 1830 fps with about 654 ft-lbs energy. As you might imagine, it sheds velocity like it's wearing a parachute and sheds energy even faster: 1040 fps and 211 ft-lbs at 100 yards. These velocities are from a long shotgun barrel.

Two wimpy-sissy-no-chamber-pressure factory 45 Colt loads are:

225 grain Semiwadcutter at 960 fps MV & 460 ft-lbs ME; at 100 yards 832 fps 346 ft-lbs
250 grain Lead Roundnose at 860 fps MV and 411 ft-lbs ME; at 100 yards 780 fps 340 ft-lbs

These velocities are from a 6" vented barrel; actual velocities froma 16" unvented barrel will be significantly higher (ESTIMATE: figure about 250 fps faster at the muzzle and maybe around supersonic (barely) at 100 yards - and the energies considerably higher)

These wimpy loads (less powerful than the original black powder loads) are noted for deep penetration in game. The 410 slug is noted for NOT having much penetration in game.

I've been loading 45 Colt ammo for over 30 years and even my sissy plinking loads are warmer than the factory loads; one of my favorite plinking loads is a hard cast 255 gr Keith style at a tic over 1000 fps (actual chronographed velocity). Serious loads for the 45 Colt are in the 44 magnum area, but I don't know if the M6 is safe with those heavy loads. Based on the factory pressure for 410, though, I'm confident that the M6 would be safe with warmer than factory 45 Colt loads.

On the other question - I doubt there is any significant loss of power with the 410 fired thru a .452 inch bore - modern plastic wads probably take that kind of out of the equation. Shotgun bores are rather sloppy to begin with in terms of acceptable range of size - compared to rifles.

Hope this helps - for what it's worth, the 410 is a heck of a lot better shotshell than the 45 Colt, but I'm still not crazy about it - anything larger than 410 is better <grin>. Don't have an M6, but I've burnt enough powder in 410 and 45 Colt to know what to expect from both.

Before anyone asks - yes, it is simpler to use a 44 magnum or 454 Casull or 480 Ruger than hot load a 45 Colt. I DO have and use a 44 Mag as well...

Regards,

Tom