Checked Precision Reloading this AM. 5 listings for 10 gauge, all “Out of Stock.” Same for three listings for 10 gauge at Ballistic Products. I shoot Goex FFFg in all my blackpowder shotshells, reasoning that light smokeless shotshell loads use fast burning powders. Started with Fg and burn throughs were common, even with new hulls. FFFg cuts burn throughs by about 90%. Check your chambers. My early mule-ear Remington comes in at 2 5/8”. Parker is 2 7/8.