Interesting. Thompson Center offered all or most of their rifles with a 1 in 48 twist rate although I know little else about their rifling such as depth and width of the grooves, yet I've seen a few of their rifles shoot patched rounds ball very well.
Keep us posted on how it shoots, will ya, Bones.
It's a shallow rifling. Made more for conicals than a PRB, but they shoot pretty good too.
Those 48" twist TC barrels had .0015 to .004" deep rifling because they were button rifled and as Hal Sharon found out, you cannot cut or impress deep grooves with a button. Yes - 1 1/2 thou, to 4 thou deep rifling.
The reason they used a button was for cost effectiveness - buttoned barrels were cheaper to produce and you could produce more per hour than with cut rifled barrels. They were not purposely made shallow for Maxiballs or any other "bullets". They were made shallow because buttoning was the cheapest method of producing a barrel - in order to keep costs down and profit margins high. This was needed, to support the most excellent warrantee - which was needed.
Later, they designed and sold the Maxiball moulds and started advertising the rifles as made for BOTH!
The barrels were made for round balls - but - most or many do shoot short conicals quite well. The REAL bullets are better - Maxiballs suck on moose.
The TC Hawkens I had, shot patched round balls very well better than the slugs, however I used a .495" ball and heavy denim that I measured at .022" compressed. That is when I learned about muzzle crowning to allow the ball and patch to conform to the bore and rifling - about 1973, within a year of starting ML shooting. My mentor was Lester H. Hawks - a new Canadian, formerly of Kalispel, Montana. He'd been shooting ML's for 30 years & knew whereof he spoke.
Here they are- most using "original" rifles.
