CRYOGENIC Treatments to Barrels

[emtrescue6]

I did a search on yahoo and pulled up some interesting information.
Here is an article in Sep 10 2010 Guns and ammos' rifle shooter magazine. by Jon Sundra
http://www.rifleshootermag.com/2010/...g_rsgunsmith1/
He states in his article:
"Some makers, like John Krieger, for example, who produces both cut- and button-rifled barrels, have embraced cryogenic stress relieving, but he makes no accuracy claims for it. Others-mostly folks who are not barrel makers but who are in the cryo business, do claim accuracy benefits for freezing the bejesus out of steel. Krieger is convinced that cryo produces a steel that is easier on tools and machines better. Those who use it all agree, of course, and those who don’t say it doesn’t.


Before cryoing, Krieger told me in a recent conversation, he would often scrap three or four barrels out of 10 because the deep-hole drilling operation would produce blanks having more than .005-inch run-out when turned on centers. It’s hard to believe that you can start drilling a hole smack in the middle of a 11⁄4-inch-diameter steel bar and after boring 28-30 inches, actually expect to come out within .005 inch of dead center at the other end!


But good barrel makers do, and now that he’s cryoing, John tells me his scrap rate because of excessive run-out is virtually nil. As with all aspects of barrel-making, the methods used to first drill the hole in the bar stock, then ream it for smoothness, vary with the maker. Some drill and/or ream on the horizontal, some on the vertical. Some rotate only the drill and/or reamer, some rotate only the barrel, others still rotate both-obviously in opposite directions."

+1...