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3/18/2010 5:19:05 PM EDT
I remember reading and article or seeing a segment on a gun show that talked about putting white out or similar substance on barrel crown to check for consistency in gas expansion or something like that. It went on to discuss barrel crown lapping or recutting barrel crown. My question is does anyone recall this article or show and where I may be able to find it? Appreciate any help.
3/20/2010 11:21:27 AM EDT
[#1]
Can't help with the article, but the technique is used to allow the "reading" of the powder residue that is left behind on the muzzle after several shots have been fired. The residue will leave a pattern on the muzzle that will be even and concentric it the crown is  properly centered. The lands and grooves will clearly show up as a multi-point star, and you can judge the quality of the crown by the evenness of the image..

The pattern shows up better on large  barreled guns and especially when using black powder.  Narrow barreled guns with  smokeless powder are more difficult.

Don in Ohio

3/20/2010 12:19:55 PM EDT
[#2]
I have used white finger nail polish in the past for this.....easier in my opinion to "read" or see the smokeless powder than white out....and normal acetone still removes it when you are done....


but don't forget to wipe it with oil afterwards...
3/21/2010 7:43:08 AM EDT
[#3]
Found the article here is the link:

http://www.gunsandammo.com/content/the-crowning-touch
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