Major Roberts (and Haarry Pope) suggest you try this...
Well, I realize this thread is an oldy but a goody, but having just read it for the first time, the initial discussion and the OP's focus on the effect of engraving on the bullet, disproportionate impact on the lower edge of the bullet and cutting by the lands triggered a memory of having read something relative to this.
Sure enough, Major Ned Roberts of Schuetzen shooting fame, writing in Hunting and Fishing July 1943 addressed this very issue in describing the advantages of muzzle to breech seating bullets in the Pope rifles as opposed to straight breech seating. For those unfamiliar with the practice, in single shot Schuetzen (200 yard offhand) shooting, it was the norm with Maynard, Ballard and other rifles prior to the Pope rifles to seat the bullet (cast) into the lands at the breech, to use a single case which was decapped, primed, and charged between each shot and a card wad placed over the charge, at which point the case was placed in the chamber such that the bullet base was optimally 1/16th" or less from the case mouth, but not actually enveloped by the case mouth. This obviously exposed the bullet base and shank to combustion and supports the view of many that the bullet filling the THROAT rather than just the bore is important to accuracy and bullet stability. Along came Harry Pope and with his rifles he supplied an indexed muzzle extension (false muzzle cut from the original barrel and indexed to the rifling) and a bullet starter, so that the bullet would be inserted into the muzzle and pushed down the barrel to seat in the breech, after which the charged case was placed in the chamber behind it. The false muzzle was removed and the shot taken. Needless to say barrel overheating was not an issue. Pope's rifles were notably more accurate and took the Schuetzen world by storm.
Major Roberts explained why this was so, in his opinion (relevant to the thread above):
A bullet loaded from the muzzle will shoot more accurately than a breech seated one because in loading the muzzle loaded bullet the lands cutting forward into the bullet leave the base perfect without any burrs behind it . Contrast this with the bullet seated in the breech; here the lands cutting backwards into the bullet drag out burrs behind it, leaving an uneven serrated base. If this bullet is not perfectly centered these burrs will be longer on one side than on the other . As these burrs leave the muzzle, the gas escapes first first from the short side, tipping the bullet to the opposite side, in which it is assisted by the longer burrs holding the bullet back; the result is an uneven, wobbling flight. The greatest essential to perfect shooting is to deliver the bullet perfectly from the muzzle; that being done, atmospheric conditions and gravity alone govern the flight and results in accurate shooting. To so deliver the bullet, it must have a perfect base, be perfectly centered and have uniform velocity. (Bold in the original article, underline added)
I can't say as I follow how muzzle loading the bullet to the breech will leave the base perfect inasmuch as it has been engraved on the way down the rifling and the lands will have cut and serrated the base, albeit with any "burrs" arising there from heading up towards the muzzle rather than back towards breech and combustion. I imagine his case was that the cuts were smaller, would seal better with obturation and allow little to no combustion gas to pass the bullet in its journey down the barrel. He makes no mention of gas checks in the cast bullets universally used though does reference paper patching, albeit not as universal practice.
His remarks do however speak directly to the points that Molly was trying to articulate and, in my understanding at least, bridge the distance to the points that 45.2 and other "old hands" were making. In any event, it has most certainly peaked my interest in having a go at breech seating some paper patched (to fill out the leade) .454 bullets in my H&R single shot 45 Colt/454 Casull (below) and to keep an eye out for a 38-55 or 32-40 Schuetzen that I can afford. :roll:
Roberts makes for very interesting reading and reaches back to an age when casting and shooting cast bullets were the norm.
Not exactly a Schuetzen but definitely a Stutzen:
http://i203.photobucket.com/albums/a...uild/001-5.jpg