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Posted: 11/26/2007 3:26:15 PM EDT
| I have noticed a strong following for chrome lined barrels. What are the benefits...and, disadvantages? What is chrome moly? What about stainless? thank you. |
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Accuracy and Throat/Barrel Life is the Trade-off Stainless will be the most accurate, but it's accurate life is the smallest. Chrome-moly is somewhere in the middle. Chrome-lined will last the longest, but will never be as accurate as a stainless because of the variable of chrome-lining. The accuracy will be completely based on the ability to chrome the bore evenly- a hard thing to do if you think about chrome lining a narrow bore the entire length evenly. Chrome also adds to relaiability becasue of it's ability to resist corrosion. There are exceptions- stainless barrels ahve been pushed beyond what anyone expected these days using different types of rifling. FN came out with a match grade chrome lined bore on their long range presision rifle. ETA: Bottomline- for general plinking/shooting- chrome lined will give the most accurate life. If you want a prescision rig, national match, or varmint gun- think stainless. Chrome-moly is just for people that can't make up their mind  (I own both chrome-lined and stainless- just depends on what you want to do)
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For higher velocity loading such as M193 at 3100-3200 fps, the CL barrel has a longer service life in terms of round count (SA or FA). IMHE, below 2600 fps; I would go for an SS Match barrel over a chrome moly barrel if accuracy is a requirement. |
| I prefer chrome lined barrels over chrome moly for an AR. It may or may not be as accurate as a chrome moly but it will last longer and have a longer accuracy life. Chrome lined will have an edge in reliability and will be easier to clean. It only costs anywhere from $35 to $50 extra dollars from most of the places that sell barrels so why not? |
If your shooting an Mforgery or other such carbine, dont worry about the supposed slight decrease in accuracy. Without dumping alot of $$$ into a match type rifle, youd never be able to tell if thats really true or not. As mentioned, the Chrome lining makes it easier to clean, the cases are less likely to be difficult to extract if theres a problem, and the lifespan is greater.
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No, it is a .gov requirement. Your so called sporting rifle are considered replaceable at your lleisure with no threat to life or limb. The AR platform (in any form) falls in both domains; hence a threat to the Brady bunch. |
Consider the time and place the AR/M16 was originally designed, and in what environments it has been and is still expected to perform in. Corrosion resistance in changing environments from salt water spray of amphibious landings, to wet, swamp and jungle battles to desert and urban warfare, is accomplished to some degree by chrome lining the bore. Changing humidity and temperatures that can be experienced in airborne drops can produce condensation, or helicopter borne assaults from amphibious ships, and so forth can cause a lot of conditions the old Remington 700 wasn't exactly designed for. Couple that with the higher volume of fire that is expected in the platform, and you can see that wear and tear is more of a concern than high precision accuracy for a general issue small arm. Remington700s that do make it to the battlefield are usually found in the hands of specially trained personnel who do not rely on the platform to pump out a high volume of fire in a short ammount of time. When was the last time you took a bolt action centerfire rifle to the range and put 500 rounds through it in a hour or two? To answer the question of whether or not it has to do with the design of the rifle or not, it is more about what the rifle was designed to do and where it is required to perform. |
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Chrome-moly is just what the steel is made of under a hard chrome lined barrel. So just think of chrome-moly as "un-lined" vs chrome lined. Standard carriers already have hard chrome internally where it is needed. It may provide a slicker and longer lasting finish on the exterior but it is not necessary or cost effective. Some say not to get chromed bolts and carrier because of hydrogen embritlement concerns. This is pretty stupid IMO as the phoshating on the stadard bolt and carrier can cause the same problems yet these same people ignore that fact and they do not run bare steel carriers either. Its like saying you prefer cars to trucks because trucks run on gasoline which is flamable.  Remington 700s do not have chrome lined barrels because they only invest about $20-30 total into the barrels of Remington 700s. If they were chrome lined it would double or triple the cost of the barrel. Plus, hunters would think it would reduce accuracy or some silly crap. |
There is nothing about stainless that makes it "more accurate". Chrome moly is just as "accurate" and possibly more so. Chrome-moly is an alloy of carbon, chromium, and molybedinum. It's easier to machine than stainless(less galling) but does not have the corrosion resistance of stainless. Some authorities say that stainless stands high heat better, reducing barrel erosion, but that's a controversial theory. Most match barrels are stainless only because of the corrosion resistance. After all, high-grade match barrels are expensive and one rust pit will cause irreparable damage. |
As long as the stockers are well made and to proper dimensions, it shouldnt matter. Mostly just flash, though the one upside I can think of is easier cleanup ( wipe clean ). Same goes for the Ti bolt carrier. Waste of money and only for show. 
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If you are on a tight budget and every penny counts, get a plain Cr-Mo barrel. If you are trying to win your state benchrest highpower rifle championship, get stainless.* For everything else, get chrome-lined. *- Stainless has the potential for best accuracy because the grade used in barrels, 416 resulphurized, has excellent machinability and will take a very good finish and can be held to very close tolerances. Not all stainless steels are difficult to machine. Note also that stainless has the potential to be accurate, it is not necessarily accurate. A stainless barrel from a discount barrel maker will likely be outshot by many Cr-Mo and chrome-lined barrels. |
As others have mentioned, chrome lasts longer than either CM or SS, perhaps 4 or 5 times as long and doesn't rust like the others. Clean up easier, yes in most cases but a match grade barrel cleans up pretty easy too. It is certainly easier to make a match grade barrel in either SS or CM compared to chrome lined due to the inability to plate it at the precise tolerances required to make a competitive match barrel. I am not saying it is impossible to do, but extremely difficult to do on a regular production basis at this point in time. That said, most shooters using ball ammo and iron sights wouldn't see the difference on target between a match barrel and a quality chrome lined barrel. The biggest reason target shooters prefer SS to CM is the way the wear pattern develops in the throat area. Imagine a dried lake bed and all the alligator like cracks on the surface. That is what the CM barrels throat resembles after a couple thousand rounds (much less with some cartridges). Now SS is not perfect either since the throat wears too, but the surface more closely resembles a rounded paving stone arrangement compared to the CM. Also the CM throat is more likely to have a small "chunk" blown out of it during its life time compared to SS, very bad for accuracy to say the least. |
As I said before, Stainless is not inherently more accurate. The main case for stainless is like I said, *supposed* resistance to thermal corrosion. You are apparently one of those who agrees with this theory, which is fine. High-level BR shooters rebarrel after 2-3K rounds anyway so that point is moot. Although you're technically correct about 416R SS, some makers' barrels are standard 416 SS, which loses the benefit of re-sulpherizing and results in a barrel not nearly as good as it could be. "Stainless" is not a magic word and not all stainless barrels are created equal(as you said). For somebody to hold the opinion that they would somehow be "disadvantaged" by shooting chrome-moly is ridiculous, and simply not true. Stainless barrels are a relatively new development and there were men shooting extremely accurate bench guns long before stainless barrels were available. I like stainless and have a multitude of stainless guns, but I just wanted the OP to be given accurate information. Here is some information from Frank Green of Bartlein Barrels: http://www.benchrest.com/forums/showthread.php?t=36192 It seems like people that like to think they know something, tell others that CM barrels are somehow junk(not meaning you) and try to lump them in with chrome-lined service barrels. The sole purpose for chrome-lining a bore/chamber is for reliability, which is imperative in a fighting rifle. There is no way with today's technology, that a barrel can be lined in chrome and still be made match-accurate( at least at reasonable cost). All chrome-lined barrels are 4140/4150 chrome-moly steel. I would think with the advancements in metal coating, that shortly stainless will be used in many more service rifles for the sheer ease-of-maintenance alone. Don't be afraid of a CM barrel in a general-use weapon. It will serve you as well as any stainless barrel, as long as you remember it WILL rust much, much easier than SS. You must keep it maintained with a clean bore where humidity is at play. Corrosion will form under the carbon/copper deposits in the bore and ruin the barrel much quicker than a SS barrel. All that said, I think the chrome-lining is money(about $40) very, very well spent in any service rifle. I've seen many chrome-lined barrels that will shoot MOA or better. What more do you need in a service rifle? Plus, 10,000+ rounds with no appreciable loos of accuracy? It's a no-brainer.  |
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