Possible trouble with sabot

[fishdoggydog]

I loaded up my muzzleloader night before deer season, 120 gr. loose pyrodex and TC Shockwave 240 gr. with the plastic tip. About 6 inches down it started to get real hard to push down, and 2 inches from my loading rod marks it was stopped. I tamped it down but decided it was not getting shot out with me holding this rifle. I pulled the breech plug, dampened powder with cleaning solution, more like soaked it, and pushed it easily out the muzzle. Cleaned up the barrel and loaded without a problem. I finally dug the bullet out of the basement trash and saw the plastic tip had bulged out the copper jacket, possibly from a short starter with too small a hole for the plastic tip? That is all can say for now, never had that happen before with my set up, and haven't looked into it further.