AR15.. Build.. Advice..

[vladtepes 1,060]

some of you know.. I am in the process of moving to America.. I have been back and forth.. up and down about what "cool" thing to get.. at first I wanted to SBR my Saiga rifle.. but then I wussed out because the gun runs SO well now I really don't want to mess with it.. then I kicked around the idea of SBR my Saiga 12.. which I may still do since it is just a shotgun and cutting the barrel a few inches should be cake.. but not %100 sure.. I finally decided I want an AR.. but I don't want to buy one this time.. I would like to build it... how hard is building an AR... I have heard it is cake.. I think I am pretty decent with the AK platform.. but have never really BUILT an AR.. what things matter.. what things don't.. are all lowers really created equal.. for those of you who know what is a good length (think SBR).. this will be a LONG process.. and I am willing to spend a few bucks to make it happen.. MIGHT even consider a suppressor at the end of all this.. but while that is a consideration it is not a priority.. while I KNOW that this is NJ and most of you have little experience with stuff like this (I have none..).. I KNOW that a lot of you guys know about ARs.. so that is why I am posting this here...

 

any help.. advice is appreciated..

[RecessedFilter 222]

If you have the machinery, and I know you are a DIYer, you should just build an AK instead.

[Pew Pew Plates 358]

Well, you dont really build ARs. You just assemble them. That being said, your best bet is so take one of these, they are actually a build and much cooler

 

 

and build this for an ultimate fun PA toy

 

[Krdshrk 3,877]

lower build is cake. Upper is a bit tougher (need more specialized tools).

 

Pre-assembled uppers make things easy

[Vlad G 345]

Uppers require maybe $50 worth of tools, no all parts are not created equal, you should probably research every single part that goes into the gun.

[Pew Pew Plates 358]

lower build assembly is cake. Upper is a bit tougher (need more specialized tools).

 

Pre-assembled uppers make things easy

[HavocMan 13]

I'm in exactly the same boat as you right now.

 

First off, let's make some important distinctions. There is a difference between "building" and "assembling".

 

The phrase "building an AK" implies that the builder is starting with a reciever flat (AK Builder), not a completed, registered reciever (NoDak Spud for instance).

 

When it comes to the AR, most folks "assemble" the rifle from a finished, registered reciever. Is that what you are planning?

 

If you can really "build" an AK, you can assemble an AR. It's a snap, almost literally. I have built a few AK's using flats from Curtis/AK Builder. I have also assembled a few AR's. The AR is much easier. Having said all that, I plan to just buy a finished lower and then a BCG. The final step will be a finished upper. I am not even going to bother "assembling" this next rifle myself - just snapping the two halves together and that's it.

 

Lowers are definately NOT all the same - the biggest difference being that some are forged aluminum and some are cast aluminum. Forged is obviously better. I plan to buy a complete lower from Bravo Company. They are consistantly good forgings that are machined correctly and anodized to mil spec. Buying a complete lower will likely cost less in the long run too.

 

The same goes for the upper - buy one configured just the way you want it from Bravo.

 

I'm also doing my next AR in stages.

 

*EDIT* You guys all beat me to the punch on the 'build vs assemble' thing! LOL - anyone see a trend?

[Recon Racoon 49]

If you have the time, space and tools you can literally build a lower receiver. Get an 80% complete lower, they're cheap, then you just use a drill press, the template they give you and your own time and you make your own receiver. Its plain forged aluminum, so you can do your own serial number, own design on the mag well, and anodize and blue the receiver to how you want it to look. You have complete control over the entire process, so you know you're getting the quality of work you put into it. Just assemble your upper, attach to the lower and you're ready to rock.

 

If you don't have the time, space or tools to build then get a build kit. DPMS offers some on the cheap, for as low as 530 dollars. Comes with everything you need, shipped to your door. You just need to buy mags. Which since you're in free America now, you could just go to a pawn shop and pick 'em for insanely cheap.

[hd2000fxdl 422]

This could get good Ant, nice thread topic,

 

Going to be watching this one, I'm pretty good with building things and even though I don't have access to a machine shop any longer I see many who don't have that much stuff building good looking and functioning AR's.

 

Now I'll sit back and watch the volley between Vlad G, Raz-o and Shane and others, this should be good.

 

 

[AnthonyG 36]

Putting the parts in the lower is easier then building a piece of furniture from walmart seriously.There is a video on assembling the lower that shows step by step exactly how to do it. I think Nick shown me the video. Buying a complete upper is worth it cause you don't save much by doing it parted out and you save the aggravation. The only time I feel getting a disassembled upper is worth it is if, you have parts already from another AR you want to use or you cant find a upper in the configuration you want. Building an AR is by far cheaper then buying a completed one. I am almost finished building mine and my total cost out the door was around $590 plus you get the sense of accomplishment lol.

[Joelk 61]

ARs are easy. If you need any tools you are welcome to borrow mine. For a first SBR I recommend a 11.5" as the 10.5" can be finicky. Do a suppressed 22 too as they are tons of fun and cheap.

 

I have a Maryland NFA Trust form if you are going the trust route, just check what PA requires. Just be patient as the NFA process is a slow one.

[vladtepes 1,060]

ok.. to be clear I have ripped apart AKs down to receiver and barrel and gone from there.. I have never bent the sheet metal or riveted them.. but I know how to bend sheet metal and I know how to press rivets... so I guess I should say I "worked on inside and out MANY AKs.."

 

I guess with the AR I plan to assemble it.. as in buy a lower.. and then pick all the parts and put them together..

 

LOL

 

now with that out of the way.. I plan to keep it simple.. but reliable... my concern rests within things like "parts kits" the lower itself.. and all that...

 

to Joel.. I am just now starting to understand the different ways I can do this.. the new gun dealer I met yesterday in PA does NFA stuff.. so he was starting to fill me in.. but I understand there is more than one way to go about it?

 

Glen.. maybe one day.. but I want an AR again.. just one.. you know.. to have.. LOL

[Joelk 61]

to Joel.. I am just now starting to understand the different ways I can do this.. the new gun dealer I met yesterday in PA does NFA stuff.. so he was starting to fill me in.. but I understand there is more than one way to go about it?

 

You can do it as in individual, which requires pictures, prints and a law enforcement sign off. You can do a trust, which is a little hassle to set up but no pictures, prints, or LE signoff. Trusts also allow multiple people to posses the items as you can have multiple trustees. You can also go corporation, but it is more hassle then the trust with the same benefits.

 

For more NFA reading go HERE and check out the FAQ and pinned threads. If you have any questions feel free to ask me as I have done been playing with this stuff for a few years and have done lots of Form 1s (to make a NFA item) and Form 4s (to transfer a NFA item).

[MarkWVU02 47]

Lower assembly is easier than most Lego kits.

[MedicYeti 96]

Easy stuff. Just a couple tools are needed if adding a barrel to the upper. Everything else is done with basic tools and punches. If you feel comfortable grinding the rivets of the AK's, then doing an AR is a piece of cake.

If you decide to add/replace a barrel pm me, I'll let you borrow the vise and wrench (just cover the cost of shipping).

[raz-0 1,259]

OK.

 

Tools you will need.

 

1) An upper receiver block. Given that it is within $5 of the DPMS one, I'd recommend the PRI one. You can do ar-15 and ar-10 pattern uppers with it.

2) A decent vise.

3) roll pin punches.

4) 1/2 socket wrench. preferably a torque wrench.

5) a hammer appropriate for banging on stuff.

 

Things you will need depending.

 

1) fore end wrench. a ton of handguards have proprietary nuts now, and often ship with a wrench. Like the troy TRX stuff.

2) castle nut wrench, if you are doing a collapsible stock.

3) Set of hex keys depending on your accessories.

 

Things that you don't need, but are nice to have.

 

1) roll pin starter punches.

 

Of course you may need some various hand tools in addition to those, like a set of screwdrivers or some pliers

 

AR15.com has a decent visual guide to assembly. The only thing in it that I find to be questionable is their instructions on using pliers to squeeze in the roll pin for the bolt catch. I use one, just not the way they show. I tape up the receiver and slide it along to whack in the pin. Your standard sized vise grips are jsut the right height to line up well and doing it that way require son ly two hands instead of three.

 

 

As for components.

 

Lowers: Forged, cast, billet, it really doesn't matter. They don't really bear much stress. What will matter is spacing of the holes for a tight fit. There are those with features like the firebird precision lowers with a built in tensioning pin, and an overtravel stop for the trigger to shorten reset. They aren't as cool as they sound. One general thing is high shelf vs. low shelf. If you think you might ever buy a legit lightning link, you need a low shelf. Low shelf is getting to be more common since the ban sunset.

 

Uppers: these are subjected to stress when firing. Forged is stronger than billet. Either way you want 7075-t6 aluminum. PRetty standard with forgings, less so with billet uppers. There are a ton of good forged uppers. For billet I like the ranier arms one. Not much heavier than a forged upper, is made out of 7075-t6, works with a bad lever, is very square and concentric, and not too pricey.

 

Barrels: Don't get a .223 chamber. .223 wylde, 5.56, 5.56 sam-r, noveske match mod whatever, all of them let you fire 5.56 without pressure issues. Stainless is more accurate. Chrome lined is more durable and easier to clean. Double chrome lined is even more durable, and a bit less accurate. Most of them are built to spec rebrands made by someone else, so do research around when you are ready to buy.

 

Triggers: there are tons of good drop ins. If you want ultra light, I'd suggest the AR-gold. If you want nice and reliable, I'd suggest Geissele. I like there superdynamic 3-gun. One to avoid is the JARD adjustable. It's a well intentioned design, but the tolerance are controlled enough form the factory to make it not a crap shoot if you cna adjust yours to where you wnat it and keep it adjusted there. JP, wilson combat, timney, knight's are all good as well. CMC is decent.

 

Stocks: if going collapsible, just makes sure the stock and the tube are the same diameter. Either both commercial spec, or both mil-spec. mixing the two is asking for it to be a PITA, or at least rattle and feel cheap.

 

Gas block: If you want to be able to shoot any cheap POS ammo, don't go adjustable. If going SBR, you may need to go for some form of adjustable because of an extra short gas system. If you are going to use a suppressor, a noveske switch block may be in order.

 

Muzzle device: You could write a novel on the subject. Folks are starting to apply actual science and fluid dynamics to them. What's best is going to change regularly. Your choice may be dictated by using a can than can QD if you go that route.

 

bolt carrier group: I already posted a detailed version elsewhere. Unless you feel like playing a balancing game, just get a decent mil-spec HPT and MPI tested unit. With a SBR you may still have to go through the various weight carbine buffers to find the right one for your gun. If building an SBR on a rifle length buffer setup for whatever reason, you cna just disassemble the buffer and replace the steel weights with chunks of 1/2" aluminum rod to tinker with wieght.

 

Foreend: I prefer free floated, but that's me. If you are going to go full auto, or bump fire a lot, and aren't going with a tube, you will prefer forend furniture with a double heat shield.

 

Outside of that, buy what you like, think looks cool, etc.

 

That's the nutshell version of what matters.

[Maksim 1,504]

Another great post worth pinning.

 

Matt, want to put together a full guide? =P

[david8613 69]

Another great post worth pinning.

 

Matt, want to put together a full guide? =P

 

 

agree, talk about fluted barrels?

[vladtepes 1,060]

thank you to all of you.. the info is appreciated..

 

to Joel.. will probably just do individual.. photos and prints don't bother me..

 

thanks to all for you for your contributions.. they are all really appreciated.. and I know will help me when I am ready to "pull the trigger" on the purchase.. lol will probably get a lower sooner than later.. then just buy the parts as I can afford them.. I guess I don't really need to apply for the NFA stuff till I am actually ready to order the barrel/upper.. as the lower itself is NOT an NFA regulated item..

[vjf915 456]

I know I'm a little late to this party. I just recently got done building my AR15. I used a complete upper, but built the lower myself. Anthony, building the lower is no more complicated than converting a Saiga.

[reed338 11]

http://www.aimsurplus.com/product.aspx?item=F1STSLBLEM&name=Spike's+Tactical+Lower+AR15+Receiver+(Cosmetic+Blemish)&groupid=53

i just bought 2 of theese lowers cant find the blems as for putting the lower parts kit togather it is not hard at all it took about an 1hr with the directions i found on line but now probably half hr. as for the upper i dont feel conterable putting that togather yet so i will buy a complete upper

[Dan 177]

Don't forget to research FCG's. They are not created equal by any means.

 

I have the Geissele SSA-E (2 stage, lightened pull) in my SPR type and a SD3G (single stage super short pull) on my multipurpose AR. They cost some bucks, but I'm now so spoiled that I can't do an AR "assembly" without one any longer. I'm sure there are other quality FCG's out there that are well worth it also, but these are the ones that I have experience with.

[raz-0 1,259]

Another great post worth pinning.

 

Matt, want to put together a full guide? =P

 

As long as nobody wants pictures anytime soon, since I don't have a lower to build.

 

 

agree, talk about fluted barrels?

 

For a given barrel weight, a fluted barrel of the same weight is more rigid. So, a 16" HBAR barrel has rgidity X. Flute it, and it is less rigid. However, lets say you have a government-ish profile that is the same weight as the fluted h-bar. The fluted h-bar will be more rigid by a fair amount. IF you managed to get a straight profiled barrel with just a raised ring for the gas block, the fluted h-bar would still be more rigid, but the difference would be not nearly so large. Someone actually took this one to the lab and measured. Thy also tested it's effect on heat soak. Fluting doesn't really increase the surface area enough to offset the loss in heat mass.

 

That being said, the risk with fluting is that it is not done uniformly and symmetrically. This can result in POI drift as the barrel heats. This is why I avoid barrels with the grenade launcher cut. Since I can't own a proper grenade launcher, why take the chance that the square flats aren't perfect. (everything else is radial cuts around the center of the bore. If that's hosed, you bought the wrong barrel).

 

Other than straight flutes:

 

helical (direction of rifling) - theoretically bad as there is the lest metal inthe direction of rotational torque.

 

helical (agianst the rifling) - theoretically good, as the most metal is left opposite of the direction of the force that creates barrel whip. nobody's seriously tested it that I have found.

 

geometrical (hexagonal, octagonal, triangular, etc) - should work like traditional fluting if the math was done right. Should also be cheaper IMO.

 

golf ball - I don't know if this will be as beneficial as traditional fluting for rigidity. It has the potential for greater weight reduction. However, I have seen version sold that don't grasp the uniform and radially symmetrical thing.

 

double helix/ diamond fluting - This is a really complicated and pricey way of getting a narrow diameter barrel. It's pretty much for looks.

 

If you REALLY, REALLY want lightest weight and maximum accuracy, get a carbon fiber wrapped barrel. Last I looked there were exactly 2 sources, both of which have production 100% spoken for by 3 or so gunsmiths. But you can get a bull barrel that weighs between a pencil barrel and a government profile barrel that is more rigid and sheds heat better than a steel bull barrel. You'll need money and patience though.

[vladtepes 1,060]

will the gun maintain accuracy going all the way down to like 11 inches? that was something I was curious about.. my 16 in ARs (223 and or 308) have always proven to be pretty accurate.. but 11.5 and I am taking 4+in off the barrel length? I know that will reduce velocity? and thus reduce range? but how will it effect accuracy? I will MOSTLY be using it as a 100 yard and in "fun gun" but any guesses on the max reasonable range?

[Dan 177]

will the gun maintain accuracy going all the way down to like 11 inches? that was something I was curious about.. my 16 in ARs (223 and or 308) have always proven to be pretty accurate.. but 11.5 and I am taking 4+in off the barrel length? I know that will reduce velocity? and thus reduce range? but how will it effect accuracy? I will MOSTLY be using it as a 100 yard and in "fun gun" but any guesses on the max reasonable range?

 

I looked into this in the past. What I discovered is that barrel length does not inherently affect accuracy. You may be able to shoot a longer barrel more accurately due to factors like balance, weight, handling, etc. As you stated, it is all about velocity, so a shorter barrel length will effectively reduce the practical operating range of the rifle through effects like bullet drop and terminal energy. For 100 yards I'd care more about bullet weight and proper twist rate for it. I couldn't tell you what the max reasonable range is, as that is half subjective and half science. Subjective is what you feel the terminal velocity/energy should be, science being the max range until the bullet becomes a mortar and starts tumbling.

[raz-0 1,259]

will the gun maintain accuracy going all the way down to like 11 inches? that was something I was curious about.. my 16 in ARs (223 and or 308) have always proven to be pretty accurate.. but 11.5 and I am taking 4+in off the barrel length? I know that will reduce velocity? and thus reduce range? but how will it effect accuracy? I will MOSTLY be using it as a 100 yard and in "fun gun" but any guesses on the max reasonable range?

 

 

Barrel length vs. accuracy is actually counterintuitive at several points. Mostly because there's a lot more going on at once than you really think about, even when you think you are thinking about it in depth.

 

Dan is partially right and partially wrong. Simply chopping some length off a barrel doesn't necessarily hurt inherent accuracy. About the only thing you can be guaranteed is that it will reduce velocity, and this will reduce the ability of a bullet to be accurate at a given range. Heck, in a vacuum, that might not even be true. But in the real world there's wind, and lower velocity means more time for the wind to push it around inconsistently. Accuracy is all about consistency.

 

But what about at 50 yards?

 

Then, a shorter barrel might be more accurate. It might also be less. Lets say you start with a 20" 3lb barrel. If you make a 12 inch 3lb barrel it is more likely going to be more accurate because it is more rigid due to more mass in the supporting structure of the barrel at every point along the barrel. It'll also take longer to heat soak. Less barrel motion when fired, more accuracy.

 

But WAIT, there's more!

 

Lets say you start with a 3lb 21" barrel, and chop is down to a 2lb 14" barrel. It may STILL be more accurate. Why? When you fire a bullet out of a barrel, you get barrel whip, which is essentially a wave. For given bullet using a given powder to push it down the barrel at a given speed, you impart barrel whip with a given harmonic frequency. If you ensure that your barrel is the right lenght so the muzzle is at a nodal point of that harmonic frequency, it moves around less, and thus is more accurate. SO our theoretical 14" barrel with cartridge A is more accurate than the 21" barrel despite being lighter and shorter. With bullet B however, that can totally change. of course the length of that wave depends on barrel length too, so you can't simply make a logn barrel, fire a round, measure the whip, and cut it down. By cutting it, you moved the nodal points. Which is why when youw ant to increase accuracy using the harmonic frequency of the barrel with a given load, then you use a harmonic dampener or something like the BOSS system (which is a kind of harmonic dampener). The accurized version of the mini-14 uses an adjustable harmonic dampener to great affect.

 

But WAIT, there's more!

 

Ok, lets say your shorter barrel is closer to a point of minimum amplitude than maximum amplitude for your bullet. Then there's the rifling. I've already stated more than once here that I prefer barrels where you get at least two full turns of rifling, as I find them to be easier to get consistent accuracy out of. Well, the reason I say this is that in a given barrel, some loads are like a prius, and some are like hopped up muscle car with crappy suspension. Tell them both to go that way as fast as they can from a stop, and one will do it with a lot more wheel spin than the other. SAme goes for bullets and rifling. In general, the lighter your bullet, the faster the rifling will bite in and get it spinning. Put it through a barrel with too fast a twist and it may fly apart as soon as it leaves the barrel. A little less twist might just make it yaw and suck accuracy wise, a little less twist, and you might still get accuracy, but you might lose a hair of velocity by turning it into angular velocity. With very heavy bullets, you get some skidding before they fully succumb to the suggestions of the rifling. Heck, some combinations it skids the whole way through, but you get enough traction to spin it fast enough to stabilize the bullet and consistently impart that much spin as long as the bullets are consistent. So you chopped down your barrel, the question is do you have enough rifling left to do the job of firing a bullet accurately. For 5.56, you can't really go much faster than 1:7 without narrowing your bullet choice significantly at best, at worst it may jsut not work for anything that you cna fit in a the case and maintain safe chamber pressure.

 

 

So what about when we push that target out past 50 yards?

 

Well, then velocity matters more and more. Less velocity means more time for wind to affect flight. Lower velocity also means slower spin, which means less stability of the projectile, which means it yaws easier, which means less accuracy the longer it is in flight.

 

I'm no expert on the subject, in fact there are whole university departments out there that focus on ballistics. It's something that has been studied for decades, and STILL occasionally makes subject matter experts go "Hunh, I wasn't expecting that"

[david8613 69]

HOLY SHIAT, i feel like gomer pyle!!!

[raz-0 1,259]

HOLY SHIAT, i feel like gomer pyle!!!

 

Eh, don't feel bad. PRetty much the rifle accurizing gunsmith's response to the general issues of length, fluting, etc. ist o try it, if it doesn't work, toss it and don't do that again. There really aren't that many variables, so trial and error can be pretty effective in reaching a legitimate conclusion.