In my case, purely by accident, the muzzle was the larger end, and believe me, I am vary cautious about inserting rods in muzzles, that is why I started it to about 4 inches past the muzzle, with a dowel, and then used a coated rod very carefully for the rest. I have the greatest respect for crowns, having several barrels for my 6PPC bench rifle, and having to deal with a bullet that has become stuck in the origin of the rifling when trying to find jam with too little neck tension from time to time. (luckily, not that often) As far as the rate at which I advanced the slugging bullet in the .22 bore goes, I would assume that anyone would understand that this needs to be done very carefully and slowly, so as not to miss any detail. A friend has learned a lot of late by casting laps on brush cores in the muzzles of lightly oiled barrels, and if needed, upsetting them, by lightly pecking the pure lead, with a carbon fiber rod and blunt jag ( The lap is longer than the core to facilitate this.) He has been able to find tight spots and lap them out, and enlarge the bore so as to leave a little choke in the last few inches at the muzzle. Recently he did a name RF barrel for a friend, one that shoots very high scores, and after it had been chambered and tested, it was pronounced a good barrel. It had been slugged before it was passed to him and found to have some irregularities. This information has not been learned from the internet. He doesn't "do" computers. He has done it on his own, but when he got around to CF, I was able to give him some information that I have gleaned from good sources, that was of some assistance. The required finishes for RF and CF are quite different.