I was just wondering if any of you fellas have had or bought a shilen chrome moly barrel from midway here lately? I am thinking about buying one but i am a little apprehensive to be down right honest. I did have one a few years back and it seemed to be ok, but that was before i really knew much about accuracy. seems to me it shot a little better than Half inch. Midway has them at a good value but sometimes you get what you pay for. Anyway i was just wondering if any of the varmint guys around here have shot them much? Lee
Shilen chrome moly barrels
- Thread starter skeetlee
- Start date
Minesweeper3433
45B/91F
I just purchased one of the CM barrels from shilen threw midway just recently and cant wait to get it threaded and shooting. I got mine on sale for 165 or so for the contored blank. Even if it is not bench rest accurate it should shoot half inch if I dont screw up the job. For that kind of price was well worth it.
I bought a threaded and short chambered stainless steel in 308 1-10 for a rem 700 from MidwayUSA. I had to buy a 308 chamber reamer from PTG and had to hand ream it only about .004 to get a good headspace. My rifle is a rem 700 with the 5r rifling. It shot OK. The best I could get was .625, But with the shilen barrel it shot a little better. I then measured the ID of the action and the bolt was .006 smaller. I ordered a PTG rem 700 bolt ground to .700 and after installation and lapping of the lugs it shoots in the 2's and 3's. It is also very easy to clean. It was worth it. I have a borescope and the rifling is very good.
I bought a Shilen chrome moly about 4 years ago for a re-barrel job on my Ruger #1. Wanted to keep the original blued finish so went with CM. Before my 'smith began his $$$$ work, I scoped it out with my Hawkeye & it did have what I considered to be unacceptable reamer marks across the lands & grooves. it was sent back and for an additional $40 it was hand-lapped, returned & 'scoped again,and was completely free of any tool marks. it is one of easiest to clean barrels, and very accurate, considering it's on a Ruger #1.
Unscrupulous, ( the dictionary definition of dishonest) sellers of used firearms also do not want to see a potential buyer arrive on the scene with a borescope, since they know their lies ( "Only been shot a few box's of ammo, and shoots in the ones"), will quickly be disproven. Big advantage for the buyer since you're not buying the proverbial pig in a poke. I've bought used Remington 700's for $250 when the original asking price was $450 after looking at the bore & showing it to the seller. I paid for the value of the receiver only, the barrel & $9.95 factory plastic stock being junk! Subtract that $200 in savings from the cost of the borescope & it becomes even more of a bargain. ;D
I wouldn't buy a gun without inspecting it with a borescope since I got mine. My factory 308 rem barrel (stainless steel) wouldn't shoot any better than .75 no matter what I tried. I got a new AIC 1.5 with the aluminum V bedding block, developed a load, attached a 3" plate to the forearm for stability when using a front benchrest, cleaning after every shot to break the barrel in, added a monopod to the buttstock. I also paid real close attention to shooting technique. I finally bought the shilen short chambered prethreaded barrel from MidwayUSA and things got better after that.
Anyway, after doing all this I bought a borescope from Brunos (best value anywhere) and inspected the factory stainless steel barrel. There was a lot of pitting about 1/2 way down the barrel. I didn't know that stainless steel would pit. It could have been an inclusion in the steel (maybe? I don't know) I also inspected a M1 carbine barrel that I had and discovered what looked like they rifled the barrel from both ends. Half way down the barrel the rifling was interrupted. Borescopes are definately a "must have tool" these days if you want to verify what you are buying is what they are advertising.
Anyway, after doing all this I bought a borescope from Brunos (best value anywhere) and inspected the factory stainless steel barrel. There was a lot of pitting about 1/2 way down the barrel. I didn't know that stainless steel would pit. It could have been an inclusion in the steel (maybe? I don't know) I also inspected a M1 carbine barrel that I had and discovered what looked like they rifled the barrel from both ends. Half way down the barrel the rifling was interrupted. Borescopes are definately a "must have tool" these days if you want to verify what you are buying is what they are advertising.
GerryM said:
There are five types of steel classified as stainless; ferritic, martensitic, austenitic, precipitation hardening and duplex. The two most commonly encountered are martensitic and austenitic.
Martensitic stainless steels in the 4XX series (US) contain significant carbon and will rust to some extent, but are classed as stainless steel. The more carbon, the greater hardness the alloy can attain from heat treatment. Sulphur is used as a machining additive in specific alloys like 416R, frequently used for barrels.
Austenitic stainless steels in the 3XX series are much more resistant to corrosion but can only be hardened through cold working, so are not suitable for barrels.
Barrel steels have stringent quality requirements regarding additive distribution so that "stringers" do not cause a potential failure condition. I had a caliber .50 BMG barrel let go when firing due to an unfortunate combination of non-uniform sulphur distribution and insufficient radial section. It is not something I would like to repeat.
Sleepygator,
The 630/17-4PH is also a martensitic steel.
Its some 16% Cr and 4% Ni makes it practically a corrosion-free alloy, while the 416R (X12CrS13) with its 13% Cr only can only be considered as resistant to corrosion. It is reputed prone to cavity(hollow) corrosion and most mills warn users about this particularity. This is most certainly primarily caused by the addition of sulphur. In the process, suphu is homogeneously included and I do not think it is the primary cause of failure. Additional cause, yes, but not the ain one.
Just to give an element of comparison I think useful to give average specifications of both 416 SS and 4140 CrMo
Brinell hardness SS416=170, 4140=235
Rm: SS416=650MPa , 4140=1000Mpa
Inbetween is the 420 (X20Cr13) used by Lothar Walther with its Brinell of 205 and Rm of 725MPa. This alloy has same Cr content as the 416, but no sulphur and carbon content is 0,20% as to the 0,12% of the 416.
R.G.C
The 630/17-4PH is also a martensitic steel.
Its some 16% Cr and 4% Ni makes it practically a corrosion-free alloy, while the 416R (X12CrS13) with its 13% Cr only can only be considered as resistant to corrosion. It is reputed prone to cavity(hollow) corrosion and most mills warn users about this particularity. This is most certainly primarily caused by the addition of sulphur. In the process, suphu is homogeneously included and I do not think it is the primary cause of failure. Additional cause, yes, but not the ain one.
Just to give an element of comparison I think useful to give average specifications of both 416 SS and 4140 CrMo
Brinell hardness SS416=170, 4140=235
Rm: SS416=650MPa , 4140=1000Mpa
Inbetween is the 420 (X20Cr13) used by Lothar Walther with its Brinell of 205 and Rm of 725MPa. This alloy has same Cr content as the 416, but no sulphur and carbon content is 0,20% as to the 0,12% of the 416.
R.G.C
Robert,
Perhaps European nomenclature is different, but 17-4 PH is generally regarded as a precipitation hardening martensitic stainless in the US, distinguished from the older 4XX martensitic series. The heat treatment regimen involves an extended soak at relatively low temperature (480-620 C) followed by by air cooling. 4XX series stainless is treated much more conventionally and similarly to chrome-moly. 4XX alloy is elevated to transformation (925-1010 C) followed by quench and temper. 17-4 PH is also well known to have stress corrosion problems, so it is not corrosion free. 416R is used as barrel steel, not for mechanical properties, but for free machining properties.
As for the catastrophic barrel failure caused by poor distribution of sulphur additives; H.P White Laboratories analyzed the failed barrel and unfired barrels. They concluded that the sulphur distribution did not meet alloy certification and was the primary failure vector, exacerbated by insufficient radial section and high pressure. I still have the report, twenty-five years later.
What you note about 420 is true. The 420 Lothar Walther uses is also well known for machining difficulties. Regardless of the stainless alloy, they are only suitable for moderate weather recreational purposes. Only chrome-moly and chrome-moly-vanadium steels are appropriate for military or cold weather use.
Perhaps European nomenclature is different, but 17-4 PH is generally regarded as a precipitation hardening martensitic stainless in the US, distinguished from the older 4XX martensitic series. The heat treatment regimen involves an extended soak at relatively low temperature (480-620 C) followed by by air cooling. 4XX series stainless is treated much more conventionally and similarly to chrome-moly. 4XX alloy is elevated to transformation (925-1010 C) followed by quench and temper. 17-4 PH is also well known to have stress corrosion problems, so it is not corrosion free. 416R is used as barrel steel, not for mechanical properties, but for free machining properties.
As for the catastrophic barrel failure caused by poor distribution of sulphur additives; H.P White Laboratories analyzed the failed barrel and unfired barrels. They concluded that the sulphur distribution did not meet alloy certification and was the primary failure vector, exacerbated by insufficient radial section and high pressure. I still have the report, twenty-five years later.
What you note about 420 is true. The 420 Lothar Walther uses is also well known for machining difficulties. Regardless of the stainless alloy, they are only suitable for moderate weather recreational purposes. Only chrome-moly and chrome-moly-vanadium steels are appropriate for military or cold weather use.
Sleepygator.
I think we say about the same in a different fashion. No point to argue at all...
The european nomenclature allow lazzy persons like me to immediately know the main characteristics of the alloy (X12Cr13=0,12%C and 13%Cr), when the numeric AISI need more lnowledge of the brands.
Regards
R.G.C
I think we say about the same in a different fashion. No point to argue at all...
The european nomenclature allow lazzy persons like me to immediately know the main characteristics of the alloy (X12Cr13=0,12%C and 13%Cr), when the numeric AISI need more lnowledge of the brands.
Regards
R.G.C
Robert said:
And, it is actually worse than that, Robert. A number of US mills have proprietary formulations, sold under trademarked names, that do not directly correspond to a specific AISI designation. Obviously, this could offer benefits if the product has some useful advantage but certainly complicates poor practitioner's lives who are just trying to make something.
I don't believe that any of the barrel makers of today would mind if you bore scoped one of their barrels. Scoping only tels part of the story as to quality.
The amount of stress in the barrel and the uniformity of the drilled hole have a lot to do with other qualitys that make a rifle barrel shoot,
I have seen barrels that look terrable under the scope but still shoot really well.
This is rare but it happens. Remember some of the barrel makers GRADE their barrels
The amount of stress in the barrel and the uniformity of the drilled hole have a lot to do with other qualitys that make a rifle barrel shoot,
I have seen barrels that look terrable under the scope but still shoot really well.
This is rare but it happens. Remember some of the barrel makers GRADE their barrels
I'm looking for the guy who can look in a barrel, with a borescope, and tell me, without a doubt, that that barrel is going to be a hummer or, a bummer. He and I are going to be rich! I'm not talking about used or, abused barrels. I know the value of a borescope when looking into a used barrel.
And, it is actually worse than that, Robert. A number of US mills have proprietary formulations, sold under trademarked names, that do not directly correspond to a specific AISI designation. Obviously, this could offer benefits if the product has some useful advantage but certainly complicates poor practitioner's lives who are just trying to make something.
[/quote]
Iknow, Steve, and it is not proper to US mills.... old norms (DIN, AFNOR,BS,WKnumbers...) , brand names, new norms..
But we are not going to hijack the thread...
Sincerely
R.G.C
[/quote]
Iknow, Steve, and it is not proper to US mills.... old norms (DIN, AFNOR,BS,WKnumbers...) , brand names, new norms..
But we are not going to hijack the thread...
Sincerely
R.G.C
DocEd said:
If you were to air gauge, measure bore straightness and scope the rifling, you could still only say that it looks good and is likely to shoot well.
butchlambert
Site $$ Sponsor
Borescopes sell a lot of barrels. The barrel makers wish all of you had one.
Butch
Butch
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.