Another question about bore lapping

[jjcoe]

First of all, I would like to say thanks for being available to answer our questions.  I recently purchased your book and have found the information invaluable.  I do have one question though.  I have a 94 Win in 44 mag.  The bore slugs .431 and is VERY rough, and leads horribly even with low velocity loads.  I wanted to know if it would be better to lap the bore, and then take the measurements for the bullets as outlined in your book and in the catalog, or should I purchase the mold, and then lap the bore in?  Didn't know if I would lap out enough metal to change measurements significantly.  Thanks for your time.

Jason

[jjcoe]

Mr. Smith,
I forgot to mention that I am new to bullet casting and was looking to purchase one of your 300 grain LFN bullets for this particular gun.  Thanks again.

Jason

[Veral]

Bores don't have to be exceptionally rough to cause severe leading.  In other words, often a bore that performs very poorly can produce steller performance with only .0002 to .0005 of 'cleanup' via lapping.  This is the thickness of Saran wrap, with only half taken off each side of the bore!

So for most guns, ordering a bullet mold .001 larger than bore diameter before lapping, will work out just fine.  For almost all rifles though, larger is better unless you are sure the chamber is too tight to chamber oversize bullets.  That means for the 44 "pistol" rifles and handguns, 432 diameter will turn in the best accuracy.  This because a fat bullet cannot tip in the cartridge while still in the chamber, and is thus started straighter into the bore.