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Posted: 8/26/2014 7:45:46 PM EDT
| Im building and SPR type rifle but with a 16in barrel. I have found a great deal on an upper but the only problem is it has a carbine length gas system instead of the mid length one I wanted. Will this make a difference? I will be shooting this upper with a scope, so Im not sure if this will be a big deal with the increased recoil that comes with the carbine length system. Should I wait and pay slightly more for the mid-length or is the difference not big enough to effect longer range shooting? |
There are plenty of 16" mid-length barrels out there. You are not even close to googling hard enough.
Check out Aero Precision for one. http://aeroprecisionusa.com/barrels/aero-precision-16-barrel-mid-length.html http://aeroprecisionusa.com/barrels/223-wylde-16-midlength-barrel.html Complete uppers available. Sionic Weapons Systems http://sionicsweaponsystems.com/store/product.php?id_product=120 Complete uppers available. Tactical Ambush http://www.tacticalambush.com/AR-15-556223-barrel-16-Mid-Length-by-Tactical-Ambush_p_172.html Complete uppers available. Not to mention Adams Arms...Voodoo barrels plus uppers. Spikes has several plus complete uppers. Your post stated you are building so these are all just barrels but no doubt that you can get complete uppers with these barrels. http://sionicsweaponsystems.com/store/product.php?id_product=23 http://sionicsweaponsystems.com/store/product.php?id_product=25 Dont settle on a carbine length system if you want a mid-length. Middie is very smooth. The masses will want you to get a PSA. Dont crumble! 
Thats all the work I am doing for you. 
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16" with carbine gas works fine, there are other variables that can affect recoil impulse, but .223/5.56 doesn't recoil much.
At 320 yds with a 12X I was able to spot my miss correct my hold over and then my reticle barely left the clay pigeons I was shooting and I was easily able to watch them break in the scope. It's easier closer in, and further out you have some time to recover before impact. A2 FH on a 16" w carbine gas, AR-15 BC, ST-2 buffer, mil-spec spring. |
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I have seen posts here about middie cycling issues with some ammo. I believe this has to do with the decreased dwell time of the middie versus carbine. It has been posted that carbines can be over gassed and therefore have a greater recoil pulse. IMHO the best solution to ensure cycling reliability and yet have milder recoil is to get a barrel with a carbine gas hole and install an adjustable gas block. An adjustable gas block allows you to compensate for nearly all ammos, especially if you reload.
A nice combo is this Black Hole Weaponry 16” barrel with a carbine gas hole (and you right now you get a free SAA Upper Receiver) http://www.surplusammo.com/saa-exclusive-16-blackhole-weaponry-1-8-hbar-profile-ar-15-barrel-nitride-series-5-56/ And An SLR adjustable gas block http://slrrifleworks.com/index.php?route=product/category&path=57 1:8 twist is what you want so you can shoot 40 to 85 (or so) grain bullets – depending on what article or post you read. 1:7 is only needed if you are going to shoot military tracers due to its OAL. And, whatever barrel you do purchase, do not get fluting – it decreased accucarcy. |
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I have seen posts here about middie cycling issues with some ammo. I believe this has to do with the decreased dwell time of the middie versus carbine. It has been posted that carbines can be over gassed and therefore have a greater recoil pulse. IMHO the best solution to ensure cycling reliability and yet have milder recoil is to get a barrel with a carbine gas hole and install an adjustable gas block. An adjustable gas block allows you to compensate for nearly all ammos, especially if you reload. A nice combo is this Black Hole Weaponry 16” barrel with a carbine gas hole (and you right now you get a free SAA Upper Receiver) http://www.surplusammo.com/saa-exclusive-16-blackhole-weaponry-1-8-hbar-profile-ar-15-barrel-nitride-series-5-56/ And An SLR adjustable gas block http://slrrifleworks.com/index.php?route=product/category&path=57 1:8 twist is what you want so you can shoot 40 to 85 (or so) grain bullets – depending on what article or post you read. 1:7 is only needed if you are going to shoot military tracers due to its OAL. And, whatever barrel you do purchase, do not get fluting – it decreased accucarcy. Say what ??? |
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Thanks! That version comes with a 1:9 twist rate. Does this matter that it's not 1:8 or 1:7? Quoted:
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Check the EE used uppers. Someone (not me) is selling the Mid length version for a good price. Thanks! That version comes with a 1:9 twist rate. Does this matter that it's not 1:8 or 1:7? If it is a PSA I think 1:9= PTAC. |
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Quoted:
Thanks! That version comes with a 1:9 twist rate. Does this matter that it's not 1:8 or 1:7? Quoted:
Quoted:
Check the EE used uppers. Someone (not me) is selling the Mid length version for a good price. Thanks! That version comes with a 1:9 twist rate. Does this matter that it's not 1:8 or 1:7? Will you be shooting any 75gr+ bullets? If not 1:9 is just fine. Quoted:
I have seen posts here about middie cycling issues with some ammo. I believe this has to do with the decreased dwell time of the middie versus carbine. The posts you refer to almost exclusively refer to one particular brand and configuration of barrel, and are NOT representative of the midlength gas system in general or even that particular gas system+barrel length configuration. For a 16" barrel length 223/556 barrel the midlength gas is a superior choice over carbine in every respect. Carbine gas 16s are not more reliable than midlength gas regardless of ammo, my experience is the opposite. The idea that a shorter gas system just adds more energy and will make it more reliable is false. A very public example of the above is the Lucky Gunner ammo tests, where they gave up trying to test Tula in their test 16" barrel carbine, and switched to a 16" midlength which was far more reliable with that particular ammo. Tula is well known to have an odd pressure curve to their powder which plays havoc with the AR15 operating system. This example demonstrates that the more-optimized midlength is able to operate over a larger performance envelope than carbine gas in that barrel length. |
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Gamma762 – I believe we agree on this point.
One data point where some dude switches to a middie rifle to get Tula ammo to work is not a trend, nor conclusive. Has any one done a scientific/engineering study of carbine versus middie. Where we can see not only the test results, but all of the tools used, the test set-up, written test procedures, meteorological data, test article data (rifle & barrel stuff), etc.; and the process was overseen by a Quality Assurance Engineer. This is how real engineers do testing – it needs to be repeatable; and repeatability is achieved by controlling all possible factors and influences (as humanly possible, naturally). Again, not some dude switching to a middie rifle to get Tula ammo to work. |
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I saw on PSA's site today at 16 middy 410 ss upper with a 12" ssk rail.
This Looks like a good start for an spr. Wish I had the coin. |
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