I’ve been shooting the 240 maximus about 3 years now, a knight disc extreme .45 1/30 twist and a rem/pac .45 1/22 twist. Harvester sb and cr. Out of a few maximus shy of 200 shot i’ve yet too blow a sabot. The rem/pac is 2630’s FPS,not sure on the knight. They both group great, the rem a little better. With the knight one hole 3 shot groups common at 100 yds. In the knight Blackhorn 209 90 grains/W, yes a stout load, save in my gun may not be in yours. Ok, first step in bullet prep.
Heat to cherry red with propane torch, drop in cold water or vinegar.
I let soak in the vinegar 20-30 mins,helps clean the scale off. Then knurl up between the bands to .402 -3. I tried knurling the full bearing but they shot better with 5/16” wide knurling. Last step - l run them,sabot and bullet threw my pacnor 458 full form die set at 3.5 to max at 4. Bullet and sabot being fed threw bullet point down so need hollow push rod - 3/8 brass tube, pipe - cut off 06 case solder. On the first pass i push on base of sabot with wood dowel as fed into die to keep both tight together 3 passes total. Also indexed 2 lands a pedal.when done bullet and sabot are locked together.