Fantastic new Blackhawk

[Quan Toi]

Veral,
     I just purchased a new in the box Ruger Backhawk 7 1/2 inch in .45 Colt. I don't think I have a problem but decided to ask you a few questions. I just slugged each chamber and I can't believe it but all of them slugged exactly .4515! The barrel is .4505 groove dia!, and it's tightest portion is the muzzle! My question is this. Should I lap it or just praise the Lord that I lucked out and got a real shooter. I'll be using a Lyman mold 452424 with your Blue soft and sized .452 and the bullets have a BHN of 14 as measured on your tester. If I do lap, how many shots should I do? I might have enough of your lapping compound left to do maybe 20 rounds. In fact I probably will order 1 of your molds in 325 grs. Thanks for all you do for the cast bullet community. I've got your book and lots of goodies in the last 15 years and have lapped many barrels, mostly in the Contender. This will be my first revolver. Thanks for your time in answering this message.
Frank
P.S. Forgot to mention, the barrel slug drops right thru each chamber/throat!

[Veral]

  I answered your email, which you sent after this post a bit differently than this.

  You be the judge.  Try shooting it as is, with several different loads,then lap and shoot some of the same loads again.  Please post your results.   Best to test accuracy at 50 yards or even farther with your stout loads, as any problems with rough leading edges on the rifling, as I described in the email, will really show up at longer ranges, but may not show a lot at 25 yards.