As has already been confirmed, the question was about Chromoly barrels not chrome lined barrels.
Chromoly or Stainless?
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As has already been confirmed, the question was about Chromoly barrels not chrome lined barrels.
Gwine
Well-Known Member
Good information guys. Some points I hadn't considered. My original instinct is SS, but was thinking of trying something different.
Now it depends on what alloy of CM 4100 family series we are talking about. Is there ia need for smaller dimensions around the chamber shank area. Such as a light barrel with no shoulder or small diameter tenon for chamber size etc. 4150 for example is going to be tougher have a higher yield pressure etc than 416R.
But the biggest complaint against cm vs ss in the accuracy game is how the throat degradation curve plays out. CM tend to have a long progressive decrease in accuracy via erosion where SS tends to hold a accuracy but then falls off the cliff so to speak as it's micro tissues finally let go with chunks breaking loose.
But here is a twist some might consider. What happens if you take a properly finished CM barrel such as a Bartlein and then have it nitrided? Yes you can do the same to SS but IMO it's more a benefit to CM.
Now you have the lower friction and smoother bore than SS and you have a similar but superior wear pattern of the nitrided surface layer sto 416R but then have the longer more gradually degregation and wear after wearing thru the micron nitride layer.
By nitriding you flip the tables on copper fouling cleaning as well as corrosion resistance etc.for CM. Not forgetting better strength and hardness of CM.
In general it's much easier to nitride CM than SS alloys. Today's it's not the issue it use to be with new more advanced tech. But still CM+ Nitriding gets you all the benefits/o qualities anof CM & SS plus more.
Speaking of chrome lined chrome moly barrels
consider the Sako TRG-21-22/41-42 use chrome moly and are chrome lined as well. The only dif is the receiver and barrels are hammer forged. The trg bores are extremely consistent which just shows CL can be played with great precision and consistency if that is desired.
My first gen TRG-22 has shot numerous sub 0.2 moa groups and 0.5 moa groups out to 1k. I have one with 4k and another with under 100 rds thru them and it takes a keen eye with a borescope in the throat to tell the diff. Maybe not up to the standards of top short range BR comp but it's still one of if not the most consistent and accurate factory mass produced rifles ever produced and with a CM CL barrel too boot.
With all that said the industry standard is SS416R for a combination of performance and machinability. There are better SS alloys that are tougher would last longer etc but are tougher on tooling. Same reason outside ARs you do not see much 4150 CMV vs 4130/4140 for CM Alloys.
When Crucible came out with SS416R it apparently from what I have read reduced a number of the weaknesses of plain SS416. By the addition of Molybdenum and a decrease in sulphur it addressed extreme cold impact resistance rating and "temper embrittlement" (personally never seen real world example outside a lab setting) down to -40F improved from 0F for AISI 416. As well as "sulphide stringers" which were a real issue as some may recall around early 2000 Tikka/Sako barrels/actions (Berreta ownership) had a large batch of high sulphur 416 that were blowing apart.
At 85% machinability of easy machining carbon steel alloy, plus the other benefits listed it's not hard to see how it became the defacto standard.
Now if someone is shoehorning a Lapua/Norma Magnum into a R700 I would be much happier with a chrome moly receiver. For that matter with it's 0.990" tenon thread diameter a CMV4150 barrel sure sounds like the better choice. I'll take the 10 points higher hardness, increased shear, fatigue, and yield strength when walls start getting that thin and pressures 65k+ are the norm.
Personally with DLC etc coatings and nitriding I would rather have a CM action period. Barrels, I'm happy with the top 416R barrels. But also my TRG CM barrels. I would have my CM barrels nitrided as I know first hand the benefits having used them approaching 20yrs now. SS either way.
(Info above pulled from personal as well as other sources not my own)
But the biggest complaint against cm vs ss in the accuracy game is how the throat degradation curve plays out. CM tend to have a long progressive decrease in accuracy via erosion where SS tends to hold a accuracy but then falls off the cliff so to speak as it's micro tissues finally let go with chunks breaking loose.
But here is a twist some might consider. What happens if you take a properly finished CM barrel such as a Bartlein and then have it nitrided? Yes you can do the same to SS but IMO it's more a benefit to CM.
Now you have the lower friction and smoother bore than SS and you have a similar but superior wear pattern of the nitrided surface layer sto 416R but then have the longer more gradually degregation and wear after wearing thru the micron nitride layer.
By nitriding you flip the tables on copper fouling cleaning as well as corrosion resistance etc.for CM. Not forgetting better strength and hardness of CM.
In general it's much easier to nitride CM than SS alloys. Today's it's not the issue it use to be with new more advanced tech. But still CM+ Nitriding gets you all the benefits/o qualities anof CM & SS plus more.
Speaking of chrome lined chrome moly barrels
consider the Sako TRG-21-22/41-42 use chrome moly and are chrome lined as well. The only dif is the receiver and barrels are hammer forged. The trg bores are extremely consistent which just shows CL can be played with great precision and consistency if that is desired.
My first gen TRG-22 has shot numerous sub 0.2 moa groups and 0.5 moa groups out to 1k. I have one with 4k and another with under 100 rds thru them and it takes a keen eye with a borescope in the throat to tell the diff. Maybe not up to the standards of top short range BR comp but it's still one of if not the most consistent and accurate factory mass produced rifles ever produced and with a CM CL barrel too boot.
With all that said the industry standard is SS416R for a combination of performance and machinability. There are better SS alloys that are tougher would last longer etc but are tougher on tooling. Same reason outside ARs you do not see much 4150 CMV vs 4130/4140 for CM Alloys.
When Crucible came out with SS416R it apparently from what I have read reduced a number of the weaknesses of plain SS416. By the addition of Molybdenum and a decrease in sulphur it addressed extreme cold impact resistance rating and "temper embrittlement" (personally never seen real world example outside a lab setting) down to -40F improved from 0F for AISI 416. As well as "sulphide stringers" which were a real issue as some may recall around early 2000 Tikka/Sako barrels/actions (Berreta ownership) had a large batch of high sulphur 416 that were blowing apart.
At 85% machinability of easy machining carbon steel alloy, plus the other benefits listed it's not hard to see how it became the defacto standard.
Now if someone is shoehorning a Lapua/Norma Magnum into a R700 I would be much happier with a chrome moly receiver. For that matter with it's 0.990" tenon thread diameter a CMV4150 barrel sure sounds like the better choice. I'll take the 10 points higher hardness, increased shear, fatigue, and yield strength when walls start getting that thin and pressures 65k+ are the norm.
Personally with DLC etc coatings and nitriding I would rather have a CM action period. Barrels, I'm happy with the top 416R barrels. But also my TRG CM barrels. I would have my CM barrels nitrided as I know first hand the benefits having used them approaching 20yrs now. SS either way.
(Info above pulled from personal as well as other sources not my own)
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elkaholic
Well-Known Member
Nitriding a Brux CM is exactly what I did with my super light 270 SS carry rifle.
Slick as can be and impervious to almost anything!
Slick as can be and impervious to almost anything!
. Thumps up
aushunter1
Well-Known Member
Most of my barrels are SS, I like them over a blued barrel mostly as they resist the weather/corrosion better.
Even when handling blued parts you leave oils etc from your hands which imo starts the process of removing/blemishing the bluing.
Ive also read they tend to resist copper fouling more as when but that could be an urban myth & more to do with quality lapping?
Even when handling blued parts you leave oils etc from your hands which imo starts the process of removing/blemishing the bluing.
Ive also read they tend to resist copper fouling more as when but that could be an urban myth & more to do with quality lapping?
David Emerson
Well-Known Member
Right up my alley. I would choose the stainless in a cut rifles barrel. I just put one together with a brux barrel on a short action Remington. WOW 3500+ with a 75 eldm and shoots bug holes. Stainless will resist erosion better and cut rifled even more.
David Emerson
Well-Known Member
I forgot to add I cut the barrel at 25 inches
jjmp
Well-Known Member
If you buy Cut rifled CM, and take good care of it , I don't see any thing to worry about , or Nitate it , their still made for good reason ,grease is cheap hint !
Savage 22-243 AI
Well-Known Member
As stated SS is easier to machine, CM takes more care. I use Ceramic liquid on inside and out of my CM barrels and have no problems. Faster break-in on SS, slow break-in on CM.
Want to upset a barrel maker? Ship them a Lother Walter SS barrel blank to machine. My gunsmith said to never send him another. Hardest material he ever worked on. He had to slow lathe speed down and change cutting oil to something different to make it work.
Want to upset a barrel maker? Ship them a Lother Walter SS barrel blank to machine. My gunsmith said to never send him another. Hardest material he ever worked on. He had to slow lathe speed down and change cutting oil to something different to make it work.
ntsqd
Well-Known Member
I'll venture that most gunsmiths have not had much experience with machining 300 series stainless steels. Trying to use Chro-Mo speeds/feeds/depths of cut is a recipe for disaster with these alloys. I've never machined any of the 416 variants, but from the comments made I'll guess that it's not a lot different from Chro-Mo. At least not in comparison to how different the 300 series SST's are. I don't view SST's as being any more or less difficult to machine when equipped with the required knowledge, and the beginning of that can be found in Machinery's Handbook.
FWIW I design and have made a fair number of parts for work using 17-4 in the H900 and H1050 conditions. The machine shops that we use all prefer this alloy as hard as they can get it. The harder that it is, the easier it is to machine and get a good surface finish on. Early-on one shop wanted it supplied annealed to be machined and then sent it out to be hardened afterwards. They told me that they'd never again do that. Annealed 17-4 is as gummy as it gets.
I consider 17-4 to nearly be a super alloy (just particularly avoid exposing it to extremely cold & saline environments) and I'd love to try a barrel made from it in the H900 or H1050 condition. Assuming that there isn't a sound metallurgical reason to stay away from it, the adventurous barrel maker who first tries this alloy and works out all of the kinks is going to really have something that raises the bar & likely corners the market.
FWIW I design and have made a fair number of parts for work using 17-4 in the H900 and H1050 conditions. The machine shops that we use all prefer this alloy as hard as they can get it. The harder that it is, the easier it is to machine and get a good surface finish on. Early-on one shop wanted it supplied annealed to be machined and then sent it out to be hardened afterwards. They told me that they'd never again do that. Annealed 17-4 is as gummy as it gets.
I consider 17-4 to nearly be a super alloy (just particularly avoid exposing it to extremely cold & saline environments) and I'd love to try a barrel made from it in the H900 or H1050 condition. Assuming that there isn't a sound metallurgical reason to stay away from it, the adventurous barrel maker who first tries this alloy and works out all of the kinks is going to really have something that raises the bar & likely corners the market.
J E Custom
Well-Known Member
Again We get back to the accuracy issue and price. Overall the 416 R Stainless is in my opinion the best buy. It has better machining abilities, better corrosion resistances over the CM and the chances of a better shooting barrel are greater because of it's machinability. (This was not always the case) Because when Stainless first came to light as a very good barrel material, not many barrel makers knew how to deal with Stainless so the military stayed with chrome Molly and the (Very)cold weather strength. but once the barrel makers developed procedures for Stainless, it became a matter of choice for them and they became more popular because of the many benefits.
The only material that I consider better is 17 4 PH But it is tough to machine and many times it is not as accurate because of its machinability. Simple truth is that "A good barrel Is a good barrel no matter what It is made of as long as the material will handle the rigors of it's use. PS: I would not recommend the use of 300 series Stainless for gun barrels because of the many problems with it.
When you buy a barrel and have to treat it, or cote it to make it competitive with other materials, the cost goes up and normally there are other issues that have to be addressed. total performance is not just barrel life, it is many other things along with it.
J E CUSTOM
The only material that I consider better is 17 4 PH But it is tough to machine and many times it is not as accurate because of its machinability. Simple truth is that "A good barrel Is a good barrel no matter what It is made of as long as the material will handle the rigors of it's use. PS: I would not recommend the use of 300 series Stainless for gun barrels because of the many problems with it.
When you buy a barrel and have to treat it, or cote it to make it competitive with other materials, the cost goes up and normally there are other issues that have to be addressed. total performance is not just barrel life, it is many other things along with it.
J E CUSTOM
ntsqd
Well-Known Member
That's just it, if a piece of 17-4 is difficult to machine I'll venture that it is not hard enough. Usually the opposite is true, but that has not been my experience with this material. Moot point though, no known to me barrels made from it.
Even though the 300 series is the most commonly used SST family, there are not many uses that it is the best choice for. Can't think of very many firearms applications where it would be the best alloy choice.
Even though the 300 series is the most commonly used SST family, there are not many uses that it is the best choice for. Can't think of very many firearms applications where it would be the best alloy choice.
300 series stainless austenistic steels are the most commonly used because of their weldability, primarily 304 and 316. If extensive machining is required before welding 303 is often used. The 300 series alloys are not considered heat treatable, nor easy to forge. I have forged 304 by hand and it is very hard under the hammer, both hand and machine. The working temperature is also very narrow, so very little work is accomplished per heat.
If primarily machined and heat treated, the 400 series martenistic alloys are utilized.
If primarily machined and heat treated, the 400 series martenistic alloys are utilized.
