Shares have increased by 95% in the last year and are up more than 70% already in 2013. That makes Cabela’s stock the best-performing in the firearms industry and one of the top-performing stocks in the U.S. in the last year. The company’s two biggest shareholders, founders Richard and James Cabela, have seen the value of their combined 25% stake jump to $1.2 billion from $750 million at the start of 2013. About one-third of Cabela’s $3.1 billion in sales last year came from firearms, ammunition and accessories, and a substantial amount of its all-important sales growth came from its...