.45Colt what size bullet

[hylander]

I slugged the barrel and throats on my ruger Vaquero
Both slugged .451
After slugging the bore I tried the slug in the throats and they were
tight but I could push them through with my thumb, pretty tight.
Should I be using .452 bullets

[Dusty Miller]

Your cylinder throats need to be about .453 for optimal performance with a .452 bullet.

[sharps4590]

Have you tried the 451's?  The bullet will obturate some on firing.

Vic

[West Creek Charlie]

Hylander

Do yourself a favor and get Veral Smiths book "Jacketed perfomance with cast bullets" and goto Aplha Precision web site and read Jim's article on revolver accuracy.

Optimally - you want a slug a .001 over bore size and throats just big enough to allow chambering of the bullet - say .0005 over bullet size.

There are many other factors that can effect accuracy and leading such as bulet hardness and lube and bore condition.

Start first by measuring your bore from both ends without runnign the slug all the way through. There is often a constriction in the bore where the barrel is screwed to the frame. Fix that by lapping if required.

Then Size your slug .001 over bore size

Then size your throats .0005 over slug size by honing with abrasive cloth. I dont like using a reamer as they leave a rough finish in the throat. Although I have one gun with rough throats and it shoots great with no leading it could cause a problem. I prefere the honing method described in verals book.

You will also need to look at your bullets - even though my two 45's are of correct dimensions they still lead the barrel if I use typical hard cast bullets and the hard lube typically found with bought hard cast. I switched to wheel weight metal cast myself and a quality lube like Felix lube and all my leading problems went away.

By all measn though - shoot the gun first - if it performs satisfactorily - leave it alone. ya never know it might just shoot great with bullets sized .451 - dotn fix a problem that doesn't exist.