Firelap Sizing

[Hairy Chest]

How do you size a bullet .0015-.002" smaller than the 'desired size' or I assume groove diameter if all sizing dies typically available are throat diameter, which is typically larger than groove diameter? 

[Hairy Chest]

Hope you are talk'n about lead bullets. You did not specify.......Appropriate dia bullet sizing die is what's used.
SOP for lead bullets is to size .001" over groove dia.
Bore dia runs on avg of .008-.009" less than groove.
LG

My question was specific to LBT's firelapping instructions.  This is LBT's exclusive question and answer section.   

Edited 2/25:  LBT answered.  Best service for customers.  Thanks, Veral.      

[Veral]

Hairy chest emailed and I answered a few days before I visited this forum.

  The copied post he gives followed by the statement that his question was to Veral/LBT, is a good thing to keep in mind because I tend to delete the answers others give to questions asked of me.  (Like I did 'Lumpy Grits' post)  I do leave many answers by other people if they know what they are talking about and the answer gives useful accurate information.

When firlapping with the LBT lap kit , just be sure your lap charged bullets are large enough to fill the grooves at the largest part of the barrel.   No amount of oversize will be a problem if the loaded rounds will chamber freely.  As a general rule, lap bullets are seated deep in the case so they don't hang up in the throat especially with pistol cartridges.  They get sized effortlessly when the power is applied as the primer pops.

  If anyone has a question which they need an answer to quickly, or if it might be a more personal nature andnot of interest to many readers, feel free to email me at   LBTisAccuracy@localnet.com

[Hairy Chest]

Hairy chest emailed and I answered a few days before I visited this forum.

  The copied post he gives followed by the statement that his question was to Veral/LBT, is a good thing to keep in mind because I tend to delete the answers others give to questions asked of me.  (Like I did 'Lumpy Grits' post)  I do leave many answers by other people if they know what they are talking about and the answer gives useful accurate information.

When firlapping with the LBT lap kit , just be sure your lap charged bullets are large enough to fill the grooves at the largest part of the barrel.   No amount of oversize will be a problem if the loaded rounds will chamber freely.  As a general rule, lap bullets are seated deep in the case so they don't hang up in the throat especially with pistol cartridges.  They get sized effortlessly when the power is applied as the primer pops.

  If anyone has a question which they need an answer to quickly, or if it might be a more personal nature andnot of interest to many readers, feel free to email me at   LBTisAccuracy@localnet.com

The gun is pretty tight.  Throats are just above muzzle dimensions and the constriction is less than .0005".  I sized them .0005" under throat diameter so they easily push through.  It will fill the groove diameter.  I didn't want to change the dimensions of the throats.   

So the question now is how much fast powder I will need and how many rounds to lose the constriction.  It's a S&W stainless.  I casted the bullets to 8 BH.  They should be the correct hardness when it's time to run them through.