GM offers (or rather offered at one time, may still be this way) cut-rifled barrels in 40, 45 and 50 cals while their buttoned barrels are offered in cals up to and including 45 but no 50s. Supposedly all cartridge rifle barrels are now made of 4140 or similar and are heat-treated twice.
GM started out small for muzzleloaders but now is quite large and makes many thousands of barrels per week, in fact I wouldn't be surprised if they're now the biggest in the US.
I'd be amazed if they didn't stand behind their products 100%. In the past I've dealt personally with their head honcho, Rick Sanborn, and found him to be a splendid fellow. I recommend them and their products and I only WISH I had some sort of financial interest in the company!
Regards, Joe
