For what it is worth I could load three loads in a row with a 300gr. bullet in a harvester sabot using Black Mag3 powder without a swab between before I lapped the bore. That is the powder I will be using for my Elk hunt this year as it is totally non fouling. I intend to finalize my sight settings this Saturday and will check the ease of loading after lapping the bore. This was with the .25ACP conversion but I will check with a standard 209 primer also this Saturday.