I am considering buying my first muzzleloader. I am much more familiar with centerfire rifles and handguns. Is the groove diameter of a 50 cal muzzleloader barrel typically .500" like a 500 S&W or or .510" like a 50 Alaskan?

It all depends. You must measure to be sure.

Brent

i just measured a traditions flint fifty cal and its aprox groove diameter is .511,, a tc pennsylvania match i have is about the same even tho the groove depth is deeper.. dont worry about this, more important is the wipe proceedure, patch thickeness, ball size, ramrod pressure of ball on powder, .. there isnt that many sizes of balls and patches to work with generally on a 50... 490 ball and .015 patch will be fine.. just be sure the jag and patch is very tight and use just enough cleaner on wipe patch so it doesnt wet powder, and still gets bore clear of fouling.you MUST repeat the wipe proceedure exactly and with exact same amount orf wipe liquid each shot to get consitent groups.. same wipe liquide, same patch thickness, etc. etc. when all these and more condidtions are met you ll be able to hit a tin can at 50 yards.. but it will take some doing.. like any thing else quality guns will give better results sooner. they will not cut pathces with sharp rifling, and smooth (not cutter chipped bores) will wipe easier.. they can be steel wooled or lapped, and etc and etc... i dont expect you to spend alot of money on your first gun. so have fun and if you like it, you can start looking at better guns or if you have a gun your really like you can get a lapped target barrel for it later.. .. dave..