Re: Long Range Muzzleloader
There are two basic symptoms of sabot failure. First, look at the gas sealing base of the fired sabot. If it is severely distorted, it probably blew through and greatly deteriorated your accuracy. Many times they will be very bulged out around the edges. Second, are all four petals there? If petals get ripped off, the sabot will not separate from the bullet in a consistent manner (ie if a petal rips the sabot may skew one direction and impact the bullet off-center).
Many people try to shoot their ML too fast in warm weather. Warm sabots fail more easily (at least I am told) so you want to keep the barrel cool.
As for the 209 primers, there is an extended section on this on the PRecision Rifle site I linked before. The guy there (Cecil Epp) is such a believer that he has a custom-modified gun that primes with .22 Hornet cases instead, and sells a modification for the T/C Encore to accomplish the same thing. Claims it tightened groups considerably. I'm a believer too from my experiences, but no such after-market mod available for my Traditions and I can't afford to upgrade.