Math check for barrel boring

[bigted]

Have this old sewer pipe muzzleloader barrel in 50 cal and would like to eventually have it bored to 58 cal and twisted to a 1 in 70 rate.

My measurements are ;
Barrel is 1 inch straight.
Groove is close enough to call .510.
Measured all dovetails and rib holes and the deepest is .135.

By my math I can take it out to a possible .620. am I rite or have I missed something?

Man this winter needs to be over or find a wheelbarrow full of spending money.

[runfiverun]

I think you forgot to divide your leftover wall thickness by 2.
your .620 will be riding the dovetail.
cutting a .580 hole will only leave 0.04 under the dovetail.
unless my math is all jacked.

[bigted]

Yep i think your right. Did something like that. Dont know now ... Will need to go measure everything again. May have missed something there as well

[bigted]

Deleting a double

[Red River Rick]

cutting a .580 hole will only leave 0.04 under the dovetail.
unless my math is all jacked.

Actually, you'll have 0.075" of material under the dovetail.

RRR

[Buckshot Bill]

Deleted

[KCSO]

According to Bill Large a 58 barrel is 1 1/8" across the flats at least. My 62's are 1 1/8 Minimum with shallow dovetails.

[C. Latch]

I once had a 1" T/C Renegade bored to 20-gauge (.620") by Ed Rayl. No problems.

[bigted]

it is indeed an old sewer pipe that was built by Thompson Center. my figures still lead me to having minimum of .075 wall left under the .135 inch deep under rib screw hole. the front dovetail is only .250 inch deep as are the rest of the holes. i also came up with the .075 inch remaining barrel meat between the bore and the rib screw hole

so question is ... is this enough "meat" left to not get into trouble?