Author Topic: Firelap Sizing  (Read 443 times)

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Offline Hairy Chest

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Firelap Sizing
« on: February 24, 2014, 08:01:41 AM »
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? 
Study after study has shown how dangerous distracted driving is yet people continue to talk on their cell phones while driving. Driving in the U.S. requires your full attention. Many states and countries have made it illegal to use a cell phone while operating a motor vehicle and the federal government should follow their lead. Banning the use of cell phones while driving would have the added benefit of making the no-texting law enforceable.

Offline Hairy Chest

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Re: Firelap Sizing
« Reply #1 on: February 24, 2014, 01:33:50 PM »

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.   8)   
Study after study has shown how dangerous distracted driving is yet people continue to talk on their cell phones while driving. Driving in the U.S. requires your full attention. Many states and countries have made it illegal to use a cell phone while operating a motor vehicle and the federal government should follow their lead. Banning the use of cell phones while driving would have the added benefit of making the no-texting law enforceable.

Offline Veral

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Re: Firelap Sizing
« Reply #2 on: February 25, 2014, 03:26:31 PM »
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
Veral Smith

Offline Hairy Chest

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Re: Firelap Sizing
« Reply #3 on: February 26, 2014, 10:47:17 AM »
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.   
Study after study has shown how dangerous distracted driving is yet people continue to talk on their cell phones while driving. Driving in the U.S. requires your full attention. Many states and countries have made it illegal to use a cell phone while operating a motor vehicle and the federal government should follow their lead. Banning the use of cell phones while driving would have the added benefit of making the no-texting law enforceable.