I had similar partial ignition on a cold range session and I'm done with it also.
Granted my original DISC is not the ideal setup, it had worked fine in warm temps.
December 25 degrees checking zero before season, giving my uncle some loading instruction, 2" fresh snow.
I was able to follow the tracks of the skipping sabot and did find one bullet of the 5 or so misfires.
I have a feeling it was due to the temp and sabot fit of the Hornady's, maybe CCI standard 209 primers also.
I meant to mention “Partial ignition” as well, BH209 WILL MOST DEFINITELY Start to ignite, and Stop! I sent Bullets to a Friend in Tennessee to Shoot in his new Knight Mountaineer, His Bore is tighter than mine, i sized the Bullets to .451-.452? Anyway they ended up loading Tighter than he felt Comfortable with, But he stil Shot Groups 1 Day while he was Waiting for his Swinglock Sizer die. He was using Oversize 1/8” Wool Felt Wads (.50 Cal Wads in his .450 Bore) The Bullets went down HARD,
After shooting, He called me and told me about a Couple of REALLY ODD things he had happen, With the Above Oversize Wool felt Wads his first Shot had Barely any Felt Recoil to it? Of course it Sounded Odd as well? The Bullet had Cleared the Barrel, But did NOT even make it to the Target, He had this happen at least 2 Different Times, SO the powder charge was DEFINITELY igniting, but also Stopping??? The only thing i can figure here is the LOSS of Pressure Through the Wool Wad, and around/Through the Rifling Grooves, it HAD TO BE THIS, Because when he Switched over to TIGHT Vegetable Fibre Wads the Problem COMPLETELY went away! He was able to Shoot Several Groups without a Hitch, But Wool Felt Wads was a NO GO!
