Traditions came out with an Express Double Over & Under .50
with an adjustable barrel system that's extremely accurate.
It handles 150 grain charges and can shoot large conicals from
its 1 in 28" twist barrels.
I'm not sure how to compare a .40 or .45 BPCR with a .50 ML.
But being an over & under, this Traditions is the most advanced
double barrel .50 muzzle loader ever produced.
http://www.traditionsfirearms.com/es...ctCode=REX-100
http://www.traditionsfirearms.com/es...ctCode=REX-101
There have been a lot of reviews although some aren't available on line:
http://www.gunsandhunting.com/traditions.html
http://www.gunsandammomag.com/cs/Sat...ifty+Times+Two
http://www.chuckhawks.com/traditions...ss_article.htm