My first AR build 2012...

Discussion in 'AR-15 Discussion' started by QFive, Jan 1, 2012.

  1. QFive

    QFive New Member

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    Hello, new guy to the forum, great info on here! I have been thinking about doing this for some time after seeing a couple people build their lowers. Seems like a fun project, but like any other hobby cars, comps, etc I can see it becoming an expensive and addicting hobby.

    So ill jump into it I will be building my first AR-15. Now this is my first AR, however I have been around rifles and other firearms most of my life i.e hunting with the pops, going to the range, some handgun aspects etc. Back on topic I will say the main purpose of this rifle is target / shtf, however accuracy is still a big part, but for a tactical carbine style AR I am paying close attention to weight. In essence FFR is not a priority (This may change).

    I picked up a Stripped Stag lower. Grabbing a PSA Lower build kit w/ milspec CTR & Miad grip soon, just trying to choose which color to go with :) I would grab the MOE kit but I am fond of the CTR friction lock.

    Onto the upper. Well this aspect is still in the air. I am looking for 5.56 chambered. Barrel wise I am fond of medium profile maybe heavy but no pencil barrels. I would run a PSA upper but the 1:7 twist standard HF barrels they run I think as of what I know about twist v. weight (which is minimal) and grain will be to aggressive for the budget ammo for target shooting. Looking in the 16" barrel size. I have checked out BCM and Del-ton as well as RRA and other mainstream manufacturers.

    In the same retrospect I am thinking about building my own upper. This all seems straight forward w/ proper gas tube sizing and tq specs, but that's what I said about the first time I stripped an engine haha. I am looking for some guidance in choosing which way to go with this. I am open to all brands granted this is on a budget but I am open to widen that IF I can truly justify the reason.

    Again I will say thank you in advance for any and all help. I am looking forward to this build and with any build I'm sure things will change. Comments welcome!
     
    Last edited: Jan 1, 2012
  2. Secondhand_Hero

    Secondhand_Hero New Member

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    Figure out what rounds you want to put through before you do anything else! 5.56 is great for multi-use. It can shoot .223 (an obviously abundant round) and 5.56 for that extra oomf. .233 rounds alone will make this a cheaper buy but you may regret it later on. Either of these two will allow you to keep lightweight. If you want to try your hand at a 7.62 you're completely changing the dynamics of your AR15 and making it a heavy bastardization with supreme killing potential. The 6.8 SPC is a great middleground between the 5.56 and 7.62 because it still keeps a close relation to build and parts as the 5.56 but still has almost as much power as the 7.62 with a little less weight.
     

  3. QFive

    QFive New Member

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    I should of mentioned this my apologies and thank you for pointing this out. I am looking for a 5.56 chamber. I am willing to take the hit on accuracy with the .223 rounds for the ability to run 5.56 safely. This is another reason why I worry about running a 1:7 twist which I may be completely wrong about so if I am feel free to correct me.

    I will edit my first post to reflect this.
     
    Last edited: Jan 1, 2012
  4. Secondhand_Hero

    Secondhand_Hero New Member

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    Very good! 16 inch barrels are realistically probably about as smart as you can get. As for the twist, it depends on the ammo grain. 1/7 twist is good, 1/9 is best. Still a dang good investment either way
     
  5. mjkeat

    mjkeat New Member

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    Chances are you're going to be using 55 grain and up, so I'd prefer and use 1:7.
     
  6. AgentTikki

    AgentTikki New Member

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    If your emphasis is on precision, get afree floating rail. I honestly don't think you'll like a hbar they really are fat bastards.

    If you looking for tacticool, y not a spr type build...maybe a wylde hybrid chamber on stainless.
     
  7. QFive

    QFive New Member

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    Good to know, thanks for the info.



    I was referring to the thread on here that has an overview of twist/grain. Would you mind going a little more in depth about how a 1:7 isn't too fast for a 55 grain?




    I wouldn't say emphasis on precision, but it is definitely an aspect I would like to retain. Not dedicated distance but still accurate. I have a few concerns going with an FFR setup since either you get a cheaper heavier rail or you pay for a lighter (still heavy) less bulky rail. The added accuracy and future additions of a vgrip and or flip up BUIS are making me think about it. Then again I could grab an railed gas block. I just don't want to lug a 9lb AR around. I mean the Midwest rails are affordable and are an option with the PSA uppers, but Idk how they rate in comparrison.

    I hear you on the hbar but if what I have been told is correct most are 1" profile for the first 7 inches thinning out to a med profile. Ill say this heavy isn't my first choice, but my research hasn't come up with many well priced medium profile barrel / full assemblies. Going off of what this site shows. If the information is incorrect then let me know otherwise.
    AR15BARRELS.COM - Barrel Profiles

    I wouldn't say for my first build that an spr would be the direction I am going, however I did go back and fourth on this for a while trying to see whether I would like more of a DMR type, SPR rifle, or lighter less accurate at distance carbine type AR.
     
    Last edited: Jan 1, 2012
  8. Snakedriver

    Snakedriver New Member

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    QFive I'm with you, I shoot exclusively 55 & 62 grain .223/5.56 ammo at ranges under 300 yards and I also believe 1/7 twist is too fast for the light stuff. Will it shoot through a 1/7 twist barrel? Sure, but I'm not convinced that it'll be accurate spinning that fast. I went with the RRA 1/9 twist upper with a 16" mid-length barrel. They use a heavy profile in their AR's that yields excellent accuracy. It's not overly heavy despite some who may think so.

    If I ever decide to begin shooting tracers and 80 grain bullets at 500 yards & more out of my AR, I'll consider getting a 1/7 twist barrel. Until then, I'll be happy with my 1/9 twist AR.
     
    Last edited: Jan 1, 2012
  9. ScottA

    ScottA FAA licensed bugsmasher Lifetime Supporter

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    I've been in communication with PSA. They are expecting some slower barrels by mid-Jan or beginning of February. Hopefully just in time for my birthday. :)
     
  10. Snakedriver

    Snakedriver New Member

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    ScottA, a little thread drift here, but my Dad was part of the TWA Team in Kansas City that restored that old Connie into flying condition. He was with TWA for 55 years. :cool:
     
  11. ScottA

    ScottA FAA licensed bugsmasher Lifetime Supporter

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    Your dad did one heck of a job. It is such a beautiful bird. I'm hoping to get a chance to tour it sometime in the near future. Maybe they'll bring it up to Oshkosh soon. :)
     
  12. Secondhand_Hero

    Secondhand_Hero New Member

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    i'll give a very basic explanation of the twist ratios. The three best suited for AR15's are 1:7, 1;8, and 1:9. For some reason the 1:8 twist doesn't show much difference in accuracy from the 1:7 twist plus it's kind of a rare, funky twist so a bit harder to find a good selection of barrels offering it. The 1:9 twist has shown superior due to slighter smaller twist. Twist rates, as forementioned, are largely suited for the heaviness of the ammo you're shooting which. If the twist ratio is too high, the bullet becomes unstable due to the low weight. If the revolutions are too low, you risk not finding the full potential of the shot. 1:7 twists are the most common to find in AR15's (even most militaries use 1:7) but on standard 16 inch barrels it's found that the twist is still trumped by the 1:9 twist. Now granted you won't be able to tell a lick of difference for anywhere up close but when you push 'er to the limits on range you'll definately be able to tell. Like i said, the grains you're using makes a difference and this 1:7-1:9 twists are best suited fpr 55-62 grains which is what you're wanting to use. i was wanting to stray away from using this much explanation earlier which is why i simply said 1:7 is good, 1:9 is best. Either way you can't go wrong! And as for the 16 inch barrels, they're the most common as well as the most plausible. 16 inch barrels are *usually* very lightweight and still do great on distance/accuracy. Barrels can get much larger but then you're taking off from the original beauty of the AR15. The are made to be compact, lightweight rifles and you're doing with barrels larger than 16 inch is add weight and sacrificing maneuvarability. So again, you're off to a good start!
     
  13. mjkeat

    mjkeat New Member

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    Secondhand you are off on your explanation of twist rate.

    1:8 is not hard to find, it is actually quite common. I have no personal experience w/ 1:8 but the reports are that the 1:8 wylde as is common place is more accurate than 1:7 and 1:9.

    1:9 has not been shown to be superior. In fact I have never heard of anyone who uses an AR for any hard use say they prefer 1:9 over 1:7. In fact most would laugh at the thought.

    Twist is subject to the length of the round more than weight.

    1:7 is suitable for weights much higher than 62 grains. Many guys use 77 grain and higher for competitive/target shooting out of 1:7.
     
  14. AgentTikki

    AgentTikki New Member

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    I think many people assume that twist rates determine the ultimate accuracy of barrel.

    Twist rates are merely a single factor. Getting a suitable rate for your intended use is important, but should not be considered an indication of the quality of a barrel.
     
  15. mjkeat

    mjkeat New Member

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    The combo of twist rate, type of rifling, and chamber along w/ overall quality.
     
  16. Quentin

    Quentin New Member

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    QFive, it's good that you're thinking this thing out. You sound like the type who will do a great job rolling your own. Most people start picking up the knowledge after their purchase!

    As far as twist rate you have to figure out now what bullet weights/lengths you'll normally use. If you'll normally go with 62gr and under, maybe even under 55gr, well 1:9 makes sense. If you'll be shooting 55 and up, then consider 1:7. As you can see there is overlap and it's right in the sweet spot of 55-62. I'd say lean toward 1:7 in a quality barrel and really look at lightweights. Later you may want to build a varmint upper...and a slower twist in a heavier barrel.
     
  17. AgentTikki

    AgentTikki New Member

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    Ill add how the crown is cut and uniformity of construction, but ya lots of stuff that can't be seen thru casual inspection. Its best to go with someone with a good rep.
     
  18. QFive

    QFive New Member

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    First off thank you all for the replies. I can see there are a few schools of thought on barrel twist. I do not plan to shoot under 55grain. Also I don't really plan to shoot larger than 62 grain. It appears most believe 1:7 is the best route and there isn't much significance vs a 1:9 twist. I understand there are other aspects in regards to barrel quality and accuracy. Also I understand ammo choice and FFR affect accuracy as well.

    Now this leads to my questions in regards to building an upper or buying an upper. Also any recommendations on quality brands and what to stay away from are welcome. In regards to quality if I am correct I believe PSA uses FN Barrels. Ive heard good things. I know there are other brands that are good. Any in particular that stand above but are still priced well?

    I am curious as to why the recommendation use a light weight barrel profile vs medium etc. I don't plan on doing mag dumps but after shooting some pencil and other thin barrels they heated up rather quickly and began to drift. Any input on this? I am assuming this is all barrel manufacturing and brand dependent such HF vs CMV vs SS barrels. I am thinking HF chrome lined but any suggestions are welcome. Ive had people say HF isn't necessity unless really abusing etc.


    Again thanks for the help so far I look forward to any tips/info you want to throw my way.
     
  19. Quentin

    Quentin New Member

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    Well the standard government profiles are as thin as the pencil barrel under the handguards, then thickens from there to the muzzle. Doesn't make much sense so why not just get the lightweight barrel in the first place and save 5 oz or more. You'd be amazed how maneuverable this makes the rifle. I haven't noticed POI drift due to heat up but I don't dump magazines either. My Daniel Defense LW midlength barrel is CHF so that may help in that regard but I agree with you that hammer forging usually is not necessary.

    Nothing wrong with building up a stripped upper but there are so many great factory built uppers configured just about anyway you want (and test fired). You don't save much or anything building an upper so most of us just build the lower and shop around for the right upper.
     
  20. jbush

    jbush New Member

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    I've kinda got the same situation going on. I want to build a 14.5 inch lightweight carbine, but almost all the barrels I've found or reasonably priced uppers have a 1:7 twist. Since this rifle will be used for general shooting it would not be unrealistic for me to find a good price on 55 gr ammo from my LGS. I'm concerned that the twist rate my be to fast for the 55 gr ammo. I'd hate to limit myself to 62 or heavier. I rarely shoot over 100 yds so this may not be an issue.

    I've read the sticky and discussions on this and other forums, but know one has said whether you lose alot of accuracy or not. Can someone chime in about 55 gr ammo in a 1:7 twist at short range (under 100 yds)