shekarchi
Member
Just wanted to share this with anyone as inpatient as me who wants to get the most out of his/her range time... I had started a thread about what would happen if you used an ice pack to cool your barrel so you could get back to shooting instead of waiting around... I wrote a materials engineering professor at U of KY. This guy knows his stuff...
Here is what he said.
Have a great weekend!
Gentlemen I heard back from Associate professor of materials Science. I guess whoever said there is a chance of warping the barrel is probably right...
Here is his reply to my question about using ice-packs to cool a hot barrel...
Have a great weekend all
Interesting question … I looked into this a bit and it seems that most barrel steel is 4140 steel, heat treated to relieve stress at 600 C and then slow cooled. So if you were to heat the barrel by rapid firing, it should not be a problem (I am not sure, but I doubt that firing would raise the temperature to 600 C) since the elevated temperature should not affect the steel microstructure and hence mechanical properties such as hardness would remain the same.
However, the method of cooling could possibly induce stresses and/or warpage in the barrel, which you of course want to avoid. Standard heat treatment would be followed by slow (air) cooling, with no stress buildup. If you were to accelerate the cooling in a uniform way, you could also avoid inducing stresses in the barrel. However, if you were to cool one part of the barrel quickly, with the rest of the barrel cooling afterward (and more slowly; also with some heat transferring back to the already cooled region), then yes, I think you could warp the barrel. Perhaps not enough to see, but this might have an influence on shooting accuracy.
If you do want to try your rapid cooling idea, you probably want to test this method on a barrel you would not mind warping. Basically, I think there is a real possibility you could affect your barrel's accuracy.
Here is what he said.
Have a great weekend!
Gentlemen I heard back from Associate professor of materials Science. I guess whoever said there is a chance of warping the barrel is probably right...
Here is his reply to my question about using ice-packs to cool a hot barrel...
Have a great weekend all
Interesting question … I looked into this a bit and it seems that most barrel steel is 4140 steel, heat treated to relieve stress at 600 C and then slow cooled. So if you were to heat the barrel by rapid firing, it should not be a problem (I am not sure, but I doubt that firing would raise the temperature to 600 C) since the elevated temperature should not affect the steel microstructure and hence mechanical properties such as hardness would remain the same.
However, the method of cooling could possibly induce stresses and/or warpage in the barrel, which you of course want to avoid. Standard heat treatment would be followed by slow (air) cooling, with no stress buildup. If you were to accelerate the cooling in a uniform way, you could also avoid inducing stresses in the barrel. However, if you were to cool one part of the barrel quickly, with the rest of the barrel cooling afterward (and more slowly; also with some heat transferring back to the already cooled region), then yes, I think you could warp the barrel. Perhaps not enough to see, but this might have an influence on shooting accuracy.
If you do want to try your rapid cooling idea, you probably want to test this method on a barrel you would not mind warping. Basically, I think there is a real possibility you could affect your barrel's accuracy.