Re: CRYO BARRELS the deep freezzz
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: P.A.R.</div><div class="ubbcode-body">The use of cryogenics treatment is used to the quicken the aging process of austenite into martensite grain structure of hardened steel.Barrels are rarely hardened these days so the process has been questioned if it is of any benefit.
Properly heat stress relieved barrels are probably not as effectively stress relived by cold treatment as poorly heat stress relieved barrels.A re-heat stress relief barrel properly done should be as effectively stress relieved as a cryo treat barrel if preformed properly on non hardened steel barrels.
If you wish to cryo treat your barrel you may do it your self by using a Styrofoam ice chest lined with plastic and covered with K1 kerosine and dry Ice ,temperatures will be below -100F which is enough to transform Austenite into the finer grain marsenite grain structure of hardened steel. I cyro treat after I harden my barrels to attain that ultimate wear that a heat treated barrel can have "Gunsmith at Large" </div></div>
Very interesting. We used to use dry-ice/acetone baths in the lab to get temperatures as low as -78C (-108F), the temperature that dry-ice sublimes at atmospheric pressure, so the kerosene method seems sound. There were other solvents/salts we'd add to get a specific temperature depending on the reaction we were trying to do.
You're description of the grain conversion at those temperature is interesting, but it seems to me you'd want to do this on the barrel stock before you did any cutting on it to get the max benefits from this.