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Thread: Stainless vs. 4150 (Barrel)

  1. #11
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    Off sand bags using 77 grain moly Black Hills ammunition, I put 4 shots into a group of 2.75" at 300 yards. Most would say that a chrome lined barrel is not capable of that level of accuracy, but that is not correct.
    Will I be the first to note "4-shot group" and "sample of one"?

    It's worth noting that provided you are using a barrel from a known high quality maker, ammo plays a HUGE part in group size and accuracy. Black Hills has a very strong reputation. You get what you pay for.

    This isn't the first i've read of 77gr SMKs doing better past 200 yards than they do at 100 yards.

  2. #12
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    Quote Originally Posted by m4brian View Post
    OK - looking for properties in general, so lets go with Palmetto State - they carry a middy with a SS barrel, and also carry a CHF barreled carbine (FN double thick chrome lined).

    Or, you could compare similar offerings in the BCM line.

    Oops - PSA also has a CHF SS - didn't see that till today.
    That SS barrel is much cheaper and lower quality than the CHF barrel. If you wanted to compare apples to apples (to a certain degree), you would compare the Noveske SS or BCM SS barrels to the CHF.

    So in this comparison, the chrome lined barrels are going to give you much longer life. The SS barrels will also be heavier. Typically, the SS barrel is going to give you between .5-.75 groups with the CHF barrel will shoot between .85-.1.25.

    So you have to figure out if that little extra bit of accuracy is worth the shorter barrel life.


    C4

  3. #13
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    wow! good info here. I'll be copying/saving for later.

    Would barrel life be longer, shorter, or not really affected if one were shooting .223 vs. 5.56 ? I would tend to think slightly longer as .223 is slightly less pressure, but perhaps it;s not enough of a differance to worry about?

  4. #14
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    Quote Originally Posted by steelonsteel View Post
    wow! good info here. I'll be copying/saving for later.

    Would barrel life be longer, shorter, or not really affected if one were shooting .223 vs. 5.56 ? I would tend to think slightly longer as .223 is slightly less pressure, but perhaps it;s not enough of a differance to worry about?



    The first thing that goes in a barrel is the throat. The hotter the loads the faster the throat will erode.


    But I think of barrels as consumable items to shooting. If barrel longevity is your goal then I would start would with a barrel that is more geared towards that than picking what loads to use. Basically it would be at the bottom of the list. The barrel and shooting habits would have far more to do with barrel life than 223 vs. 556.

  5. #15
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    Quote Originally Posted by steelonsteel View Post
    wow! good info here. I'll be copying/saving for later.

    Would barrel life be longer, shorter, or not really affected if one were shooting .223 vs. 5.56 ? I would tend to think slightly longer as .223 is slightly less pressure, but perhaps it;s not enough of a differance to worry about?
    Where is the data showing the 223 is loaded to lower pressures? When a 223 is fired from a 223 chamber, it delivers similar velocities to a 5.56 fired from a 5.56 chamber. To do so, the 223 must generate similar chamber pressure.

    The difference between the two is the longer leade of the 5.56. This means the bullet of the 223 has a longer distance to travel in the 5.56 chamber than it does in the 223 chamber which lowers chamber pressures. The 223 gives less velocities in a 5.56 chamber not because the 223 is loaded to lower pressures, but because the 5.56 chamber is configured wrong to give best performance with 223 loads.

    The pressure data for SAAMI and NATO do not directly compare. Pressure readings are take from different locations with different piezoelectric transducers
    Last edited by MistWolf; 09-10-11 at 12:10.
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  6. #16
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    Grant: Thanks for the apples to apples...

    But on the PSA, would a CHF SS barrel give closer to the best of both worlds having the hardness of CHF?

  7. #17
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    To be perfectly honest, that is the first hammer forged SS barrel I've ever seen.

    It's an intresting concept though...I'd be courious as to what kind of life one could expect.

    It's worth noting that you don't see hammer forged barrel in the benchrest community. There cut rifled barrels seem to dominate. But obviously, accuracy by far is the concern there. Hammer forge machines are extraordinarily expensive. Therefore I suspect PSA isn't turning them out, but are sourcing them. I just wonder from where.

    Where is the data showing the 223 is loaded to lower pressures? When a 223 is fired from a 223 chamber, it delivers similar velocities to a 5.56 fired from a 5.56 chamber. To do so, the 223 must generate similar chamber pressure.
    Same overall cartridge length, more powder. My understanding is the longer throat of the 5.56mm chamber relieves the extra pressure of ammunition loaded to 5.56mm velocities. The chamber doesn't determine the velocity as much as the makeup of the cartridge. Any reloading manual will list more powder for 5.56mm rounds as opposed to .223.

    When a 223 is fired from a 223 chamber, it delivers similar velocities to a 5.56 fired from a 5.56 chamber.

  8. #18
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    A longer leade effectively increases case volume which leads to a reduction of pressure. What that means is the 223/5.56 will need more powder to achieve the same pressure in a 5.56 chamber that it will have in a 223 chamber. The lower pressure will reduce velocity.

    Even with the increased leade, the effective case capacity difference between the 223 and 5.56 is small and very little, if any, velocity difference will be seen between the two when used in their respective chambers.

    The 5.56 is designed with reliable function in mind and the 223 for better shot to shot consistency. Most, if not all military chambers have a looser fit, as their civilian counterparts are often tightened up in pursuit of improved accuracy, and to allow more of a safety margin for varying pressures from lot to lot of ammunition
    Last edited by MistWolf; 09-10-11 at 22:16.
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  9. #19
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    Quote Originally Posted by bp7178 View Post
    To be perfectly honest, that is the first hammer forged SS barrel I've ever seen.

    It's an intresting concept though...I'd be courious as to what kind of life one could expect.

    It's worth noting that you don't see hammer forged barrel in the benchrest community. There cut rifled barrels seem to dominate. But obviously, accuracy by far is the concern there. Hammer forge machines are extraordinarily expensive. Therefore I suspect PSA isn't turning them out, but are sourcing them. I just wonder from where.
    Can you link to this? I can't find any uppers on PSA's website that have a CHF SS barrel. I see CHF uppers, and I see SS uppers, but nothing with a mixture of the two.

    As for the CHF, PSA says right on their page that they're sourced from FN. No mystery there...

  10. #20
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    http://palmettostatearmory.com/2421.php

    This is a limited edition 5.56 NATO upper with a free-floated 20" FN Hammer Forged Stainless Steel barrel. Quantities are limited, so order now before they are gone!

    Barrel: FN marked, 20" Hammer Forged Matte finish chrome-lined stainless steel with an A2-style profile, individually high pressure tested and magnetic particle inspected. Chambered in 5.56 NATO with a 1:7 twist , Rifle-length gas system, and M4 feedramps. Barrels are finished off with a low profile gas block, Midwest Industries T-15 Quad rail, and an A2 flash hider.

    Upper: Forged 7075-T6 A3 AR upper is made to MIL-SPECS and hard coat anodized black for durability. Featuring machined T marks, and a mil-spec finish. These uppers are made for us right here in the USA by a mil-spec manufacturer, and are marked with the Palmetto State Armory logo on the left side, up front, just below the rail.

    Bolt: Bolt is made of Mil-spec Carpenter 158 steel, Shot peened, MPI and HPT. Gas key is secured with grade 8 fasteners and staked per mil-spec. Bolt carrier is parkerized outside, chrome lined inside, and laser engraved with the Palmetto State Armory logo
    So its a FN barrel, but I didn't know you could chrome SS. I wonder if they cut and pasted the description from something else. I'm not seeing the benefit of a chrome lined stainless barrel...if you are selecting a stainless barrel...then to chrome it...hmmm.

    I've heard of salt bath nitride on stainless barrels, and IIRC, they do this to .338 Lapua barrels. I think Noveske even holds a patent on some type of manufacturing process involving salt bath.

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