Cryo~??
- Thread starter COLT45SA
- Start date
jackieschmidt
Gold $$ Contributor
The very best 30 caliber barrel I ever owned is a 1-18 twist Krieger that is from the era when they were cryo treating their barrels. Of course, it could have been one of those barrels that was simply born good.
Cryo is a sound in theory. It does help complete the transformation of Austenite to Martensite in the tempering of alloy steels. It is also said, in theory, to stabilize the grain structure in non ferrous metals such as titanium and aluminum, increasing resistance to shock at high strength levels.
Is this a factor in a Rifle barrel? Probably not.
I’m not sure the people that were doing it were actually following the correct Process . There is more to it than simply cooling it down to -300 degrees F.
Cryo is a sound in theory. It does help complete the transformation of Austenite to Martensite in the tempering of alloy steels. It is also said, in theory, to stabilize the grain structure in non ferrous metals such as titanium and aluminum, increasing resistance to shock at high strength levels.
Is this a factor in a Rifle barrel? Probably not.
I’m not sure the people that were doing it were actually following the correct Process . There is more to it than simply cooling it down to -300 degrees F.
U need To go back n research the articles in Precision Shooting . A lot of testing by Gaza Nagy. Results were better in button bbls vs cut bbls. There were numerous examples of bbls that changed POI as they heated up. Cryo tamed those bbl.
Krieger ( who probably didn’t need to) cryoed their bbl after profiling n finishing.
Cryo treating is an extra cost step that a cut bbl does not seem to need.
Krieger ( who probably didn’t need to) cryoed their bbl after profiling n finishing.
Cryo treating is an extra cost step that a cut bbl does not seem to need.
jackieschmidt
Gold $$ Contributor
From what I remember 15+ years ago, Krieger cryoed their barrel blanks before their machining operations for one purpose, to improve the tool life in deep hole drilling, reaming, and cutting the rifling.
Any other benefits were welcome.
Liven The Dream
Gold $$ Contributor
Well from a time long long ago .
Boots Obermeyer did all His Blanks before it got Popular.
He told us at a Match one day “ He sent in on a Palit Board load “.
He made great Barrels !
Boots Obermeyer did all His Blanks before it got Popular.
He told us at a Match one day “ He sent in on a Palit Board load “.
He made great Barrels !
WSnyder
Silver $$ Contributor
And yet several years ago Krieger quit cryo altogether because they finally admitted it did nothing to add to the process.
Some years back, a Hall of Fame shooter, who owns several current records, told me that back when cryo was a hot topic, that he had a really good shooting cut rifled barrel for his rail gun. Hoping to extend its life, he had it cryoed along with a couple of others. It was done by a prominent company. After the work was done, it was no longer competitive.
Back when Doug Shilen was running the barrel company, he spent a lot of money investigating whether cryo would stress relieve 416 steel like their stress relief furnace. His conclusion was that it didn't.
I believe that the best time to cryo barrel steel is before any machining is done.
Recently I asked someone at Kreiger if they were still cryoing their steel. They aren't. I was told that the steel that they are currently using is drilling better than the stuff that they were using when whey were, after cryo. With better steel, they believe there is no benefit.
Back when Doug Shilen was running the barrel company, he spent a lot of money investigating whether cryo would stress relieve 416 steel like their stress relief furnace. His conclusion was that it didn't.
I believe that the best time to cryo barrel steel is before any machining is done.
Recently I asked someone at Kreiger if they were still cryoing their steel. They aren't. I was told that the steel that they are currently using is drilling better than the stuff that they were using when whey were, after cryo. With better steel, they believe there is no benefit.
ELR LVR
Silver $$ Contributor
I had a Savage 22-250 "Freeze dried"
It went from 3/4" MOA
to 1/4-3/8" MOA
And also cleaned easier afterward as if it hardened/toughened the surface or something.
---------------------------------------------
I had no idea the Mfgr's stopped doing it
Many like Krieger say stress relieved
I thought this was still the process used.
What process is used now then?
It went from 3/4" MOA
to 1/4-3/8" MOA
And also cleaned easier afterward as if it hardened/toughened the surface or something.
---------------------------------------------
I had no idea the Mfgr's stopped doing it
Many like Krieger say stress relieved
I thought this was still the process used.
What process is used now then?
My first custom AR barrel was a Lilja from John Holliger at White Oak Precision. It was frozen. I got over 6,000 rounds from that barrel and was still shooting well when I had it pulled from that upper 2 years later. It didn't foul much and also cleaned very easily. Did the Cryo work? Who knows...
I think I have one cryo barrel still, its on a Weatherby Accumark from years ago. Its shoots well, but is nothing to brag about. I had a Weatherby Super Predator Master that was treated for a while, same thoughts.
XCaliber has it as an option. A friend of mine opted to save $50.00 and go that route vs a Bart chambered by a smith of his choice. He is certain the extra $100.00 he spent on the treatment was a bad choice. He is very experienced and well versed in load development, but this barrel has disappointed him.
XCaliber has it as an option. A friend of mine opted to save $50.00 and go that route vs a Bart chambered by a smith of his choice. He is certain the extra $100.00 he spent on the treatment was a bad choice. He is very experienced and well versed in load development, but this barrel has disappointed him.
There is so much misinformation on the internet about the Cryogenic treatment of barrels.
I have a lot actual hands on experience with deep cryogenic treatment of barrels and stress relieving of 416 stainless. A proper deep cryogenic treatment cycle will improve a 416 stainless barrel regardless of the manufacturing process.
The cryogenic process like all other thermal operations is best performed on a cylindrical blank prior to contouring regardless of the rifling process. Cryogenic processing should be conducted prior to contouring and final lapping.
If a finished barrel is cryo treated the interior dimensions will shrink. The amount of shrinkage will vary based on a few factors.
These small dimensional changes are the reason that high end race engine shops normally perform the cryogenic processing prior to final machining on engine parts.
Cryo alone will not fully stress relieve a barrel.... it takes heat and then cryo
Think of it this way.... a NOS system will greatly enhance the performance of your hot rod but you can't run it on NOS alone.
The process is more than just dipping a barrel into liquid nitrogen... That's Bad
Stress relieving barrel material is like old people sex... It needs to happen slow and easy.
The deep cryogenic process slowly ramps the material down from ambient to -300F or colder over several hours. The temperature is held at -300F or colder for 10-24 hours to allow the material to be thoroughly soaked to complete the transition of austenite to martensite. After the soak the temperature is allowed to slowly return to ambient and this warming up process may take 24 or more hours. The last step is to temper any newly formed martensite and that is done by raising the temperature of the material and soaking it at +300F for 1-3 cycles. This is a general idea of the process. Each material and processor will have their own specific recipe.
Yes it's a lot of extra work to manufacture a cryogenic treated barrel but it's worth it.
- Cryogenic processing of rifle barrels has not went away.
- All barrel steel has some amount of residual stress in it from the steel mill. How your barrel maker deals with this residual stress within the manufacturing process will determine the quality of the barrel.
I have a lot actual hands on experience with deep cryogenic treatment of barrels and stress relieving of 416 stainless. A proper deep cryogenic treatment cycle will improve a 416 stainless barrel regardless of the manufacturing process.
The cryogenic process like all other thermal operations is best performed on a cylindrical blank prior to contouring regardless of the rifling process. Cryogenic processing should be conducted prior to contouring and final lapping.
If a finished barrel is cryo treated the interior dimensions will shrink. The amount of shrinkage will vary based on a few factors.
- The amount of any remaining residual stresses in the barrel at the time of cryo
- The outside contour will effect the shrinkage areas and rates.
- Barrels that have not been stress relieved as part of the manufacturing process will shrink more than the ones that have been subjected to a post steel mill stress relief.
- Even with this variable shrinkage rate most people often find improvements in barrels but the only way to be for certain is to include the cryogenic process as part of the manufacturing process.
These small dimensional changes are the reason that high end race engine shops normally perform the cryogenic processing prior to final machining on engine parts.
Cryo alone will not fully stress relieve a barrel.... it takes heat and then cryo
Think of it this way.... a NOS system will greatly enhance the performance of your hot rod but you can't run it on NOS alone.
The process is more than just dipping a barrel into liquid nitrogen... That's Bad
Stress relieving barrel material is like old people sex... It needs to happen slow and easy.
The deep cryogenic process slowly ramps the material down from ambient to -300F or colder over several hours. The temperature is held at -300F or colder for 10-24 hours to allow the material to be thoroughly soaked to complete the transition of austenite to martensite. After the soak the temperature is allowed to slowly return to ambient and this warming up process may take 24 or more hours. The last step is to temper any newly formed martensite and that is done by raising the temperature of the material and soaking it at +300F for 1-3 cycles. This is a general idea of the process. Each material and processor will have their own specific recipe.
Yes it's a lot of extra work to manufacture a cryogenic treated barrel but it's worth it.
Good info from a poster that knows what he's talking about. Thanks very much for the post!There is so much misinformation on the internet about the Cryogenic treatment of barrels.
- Cryogenic processing of rifle barrels has not went away.
- All barrel steel has some amount of residual stress in it from the steel mill. How your barrel maker deals with this residual stress within the manufacturing process will determine the quality of the barrel.
I have a lot actual hands on experience with deep cryogenic treatment of barrels and stress relieving of 416 stainless. A proper deep cryogenic treatment cycle will improve a 416 stainless barrel regardless of the manufacturing process.
The cryogenic process like all other thermal operations is best performed on a cylindrical blank prior to contouring regardless of the rifling process. Cryogenic processing should be conducted prior to contouring and final lapping.
If a finished barrel is cryo treated the interior dimensions will shrink. The amount of shrinkage will vary based on a few factors.
- The amount of any remaining residual stresses in the barrel at the time of cryo
These small dimensional changes are the reason that high end race engine shops normally perform the cryogenic processing prior to final machining on engine parts.
Cryo alone will not fully stress relieve a barrel.... it takes heat and then cryo
Think of it this way.... a NOS system will greatly enhance the performance of your hot rod but you can't run it on NOS alone.
The process is more than just dipping a barrel into liquid nitrogen... That's Bad
Stress relieving barrel material is like old people sex... It needs to happen slow and easy.
The deep cryogenic process slowly ramps the material down from ambient to -300F or colder over several hours. The temperature is held at -300F or colder for 10-24 hours to allow the material to be thoroughly soaked to complete the transition of austenite to martensite. After the soak the temperature is allowed to slowly return to ambient and this warming up process may take 24 or more hours. The last step is to temper any newly formed martensite and that is done by raising the temperature of the material and soaking it at +300F for 1-3 cycles. This is a general idea of the process. Each material and processor will have their own specific recipe.
Yes it's a lot of extra work to manufacture a cryogenic treated barrel but it's worth it.
ELR LVR
Silver $$ Contributor
I
I've heard Krieger, one reason I choose them
Stress relieves their barrels or are stressed relieved BEFORE cut rifling them
So that way, they are stress free during machining
which I heard also helps them from walking when they heat up
Good info, thanks manThere is so much misinformation on the internet about the Cryogenic treatment of barrels.
- Cryogenic processing of rifle barrels has not went away.
- All barrel steel has some amount of residual stress in it from the steel mill. How your barrel maker deals with this residual stress within the manufacturing process will determine the quality of the barrel.
I have a lot actual hands on experience with deep cryogenic treatment of barrels and stress relieving of 416 stainless. A proper deep cryogenic treatment cycle will improve a 416 stainless barrel regardless of the manufacturing process.
The cryogenic process like all other thermal operations is best performed on a cylindrical blank prior to contouring regardless of the rifling process. Cryogenic processing should be conducted prior to contouring and final lapping.
If a finished barrel is cryo treated the interior dimensions will shrink. The amount of shrinkage will vary based on a few factors.
- The amount of any remaining residual stresses in the barrel at the time of cryo
These small dimensional changes are the reason that high end race engine shops normally perform the cryogenic processing prior to final machining on engine parts.
Cryo alone will not fully stress relieve a barrel.... it takes heat and then cryo
Think of it this way.... a NOS system will greatly enhance the performance of your hot rod but you can't run it on NOS alone.
The process is more than just dipping a barrel into liquid nitrogen... That's Bad
Stress relieving barrel material is like old people sex... It needs to happen slow and easy.
The deep cryogenic process slowly ramps the material down from ambient to -300F or colder over several hours. The temperature is held at -300F or colder for 10-24 hours to allow the material to be thoroughly soaked to complete the transition of austenite to martensite. After the soak the temperature is allowed to slowly return to ambient and this warming up process may take 24 or more hours. The last step is to temper any newly formed martensite and that is done by raising the temperature of the material and soaking it at +300F for 1-3 cycles. This is a general idea of the process. Each material and processor will have their own specific recipe.
Yes it's a lot of extra work to manufacture a cryogenic treated barrel but it's worth it.
I've heard Krieger, one reason I choose them
Stress relieves their barrels or are stressed relieved BEFORE cut rifling them
So that way, they are stress free during machining
which I heard also helps them from walking when they heat up
Just speaking generally but most cut bbls rely on the steel mill for stress relief as opposed to having that ability in-house. Not saying one is better than the other but I prefer small batches and better control of the process vs huge batches done at a mill. But trhe subject is cryo, which is a step further and has a somewhat different effect than heat stress relieving..and a different purpose. Cryo does not replace heat stress relieving.
butchlambert
Site $$ Sponsor
300 below is not a true cryo and temp is not all of it either.
ELR LVR
Silver $$ Contributor
Is there some vibratory action going on to help release the air bubbles?
butchlambert
Site $$ Sponsor
Air bubbles in liquid nitrogen?
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