Mega Gator multi cal lower.
DPMS LPK installed.

Mega Flat top upper w/ feedramps
w/mega charging handle, fwd assist, door installed.

The Barrel will be a chrome lined 14.5 inch with 1:9 twist.

I figure a Bushy or RRA bolt and bolt carrier oughta work, anything I need to know about them, pros or cons?

Vortex flash hider

I will be sending out funds for an Eotech Thursday morning.

What's a good gasblock/bayo lug set up that'll work fine for my buis?

There is an insane amount of BUIS set ups around, what's a solid, accurate, cheap set up?

LMT 6 pos collapsible stock.



Questions. How do I order the gas tube to be the correct length for the barrel?

What is the best combination of price and quality on a 4 rail handguard stock?

Are the Tango Down VFG's worth the extra price over a generic VFG?

(stupid noob alert) How do you not get in trouble for having all the parts to build an AR, and the barrel only be 14.5 when it's shipped to you before you attach the flash hider? Or do I need to order it already attached or what?

I see different handguard lengths on different length barrels, how much length do I need for a stock bayonet to work? Or will a bayonet even work with the flash hider I want?


Counting the Eotech, Upper, and lower I've dropped about 7 bills, I'd like to bring everything else in for under $500. Possible? Stupid to even think it or what? Thusday I'll be ordering everything I don't buy in person at the gunshop. So I'd like it finalized by then.


Also, on mags, USGI mags are the best money/quality combo right?


Am I forgetting anything? Go easy on me, I came here for the pistol stuff, but got bit by the bug and had to have one. Looked for awhile but couldn't find one set up like I want so decided to build my own. Thanks ya'll.

I wouldn't use the DPMS LPK based on my experience.
The FH you seek sounds like a vortex.

If you are trying to keep costs down, and are definately going with the EOTech, skip the BUIS. For that matter, skip the VFG. It's not like you can't add it later.

If the bbl is 14.5" with a carbine lenght gas setup you should be good to go provided your FSB has a lug. And that will also answer your question about the gas tube length.

Quoted: I wouldn't use the DPMS LPK based on my experience. The FH you seek sounds like a vortex. If you are trying to keep costs down, and are definately going with the EOTech, skip the BUIS. For that matter, skip the VFG. It's not like you can't add it later. If the bbl is 14.5" with a carbine lenght gas setup you should be good to go provided your FSB has a lug. And that will also answer your question about the gas tube length.

The LPK was in the lower when I bought it, I personally would have put an RRA kit in it.  So is the gas port location on the barrel standard? Meaning if I call up RRA and say I want a 14.5 inch 5.56 barrel with a 1:9 twist and chrome lining. I can then just order "carbine length" hand guards and gas tube and it all match up?

Quoted: Mega Gator multi cal lower. DPMS LPK installed. Mega Flat top upper w/ feedramps w/mega charging handle, fwd assist, door installed. The Barrel will be a chrome lined 14.5 inch with 1:9 twist. This all seems to be good I figure a Bushy or RRA bolt and bolt carrier oughta work, anything I need to know about them, pros or cons? Either one should be fine. [noob alert] The 4 prong flash hiders I keep seeing look badass I dunno the name of them, what are their pros, cons, etc? I believe you are refering to the Vortex flash hider.  Pro- works really well.  Con- some people hear a ringing after a shot.  Kind've like a tuning fork. I will be sending out funds for an Eotech Thursday morning. What's a good gasblock/bayo lug set up that'll work fine for my buis? There is an insane amount of BUIS set ups around, pros and cons of various brands? Its been discussed to death.  Do a search and find the one that suits you best. 6 pos collapsible stock. (Whatever I find on the EE or my old gun guys shop thursday cheap) Questions. How do I order the gas tube to be the correct length for the barrel? It will be designated by the gas system.  If your barrel has a carbine gas system, you will need a carbine length gas tube. What is the best combination of price and quality on a 4 rail handguard stock? Depends on if you want free float or not. Are the Tango Down VFG's worth the extra price over a generic VFG? (stupid noob alert) How do you not get in trouble for having all the parts to build an AR, and the barrel only be 14.5 when it's shipped to you before you attach the flash hider? Or do I need to order it already attached or what? Do not have the barrel assembled into the upper reciever.  As long as it can't be slapped onto the lower and fired, I doubt it would be considered constructive intent. I see different handguard lengths on different length barrels, how much length do I need for a stock bayonet to work? Or will a bayonet even work with the flash hider I want? To get a bayo to work, you will either need an extended bayo or a barrel using a midlength gas system, assuming you are using the 16 barrel and a flash hider.  If using the 14.5 and pinned flash hider, no problems Counting the Eotech, Upper, and lower I've dropped about 7 bills, I'd like to bring everything else in for under $500. Possible? Stupid to even think it or what? Thusday I'll be ordering everything I don't buy in person at the gunshop. So I'd like it finalized by then. All depends on how extravagent you get with the barrel and railed handguard. Also, on mags, USGI mags are the best money/quality combo right? Yes Am I forgetting anything? Go easy on me, I came here for the pistol stuff, but got bit by the bug and had to have one. Looked for awhile but couldn't find one set up like I want so decided to build my own. Thanks ya'll. Just ammo

1)If you are a total noob, I would skip the Eo-Tech for now, as well as the gasblock.  Use a standard FSB preinstalled on the barrel.  Put a quality BUIS on the receiver, and shoot it for a while with just the iron sights.  It is an essential skill.

2)I would use a CMT (Stag) bolt carrier group and charging handle.  Very high quality at a reasonable price.

3)  I would actually skip the 14.5" barrel.  You are hardly building a replica from your description.  With the 14.5" barrel, you are giving up velocity and the convenience of a removable flashhider, plus additional cost (at least $50) all to save 1" on overall length.  I would stick with a chrome lined 16".  If you do decide to go with a 14.5", I would buy a Bushmaster 14.5" M4 with permanent Phantom from PK Firearms.  

4)  Whatever stock you decide on, make sure it uses the milspec buffer tube.  Stag, Colt, LMT are the only companies I can think of that sell complete stocks with the milspec buffer tube.  You need the mil-spec tube if you later want to change out the stock for a Magpul, VLTOR or other replacement.  If you buy a non-milspec stock (RRA, DPMS), you will end up having to buy a new buffer tube in order to replace the stock.

Quoted: I wouldn't use the DPMS LPK based on my experience.

Based on mine, I wouldn't use anything else.  I have two of them and an RB Precision kit that uses mostly DPMS parts, and all have been great.

Quoted: 1)If you are a total noob, I would skip the Eo-Tech for now, as well as the gasblock.  Use a standard FSB preinstalled on the barrel.  Put a quality BUIS on the receiver, and shoot it for a while with just the iron sights.  It is an essential skill. 2)I would use a CMT (Stag) bolt carrier group and charging handle.  Very high quality at a reasonable price. 3)  I would actually skip the 14.5" barrel.  You are hardly building a replica from your description.  With the 14.5" barrel, you are giving up velocity and the convenience of a removable flashhider, plus additional cost (at least $50) all to save 1" on overall length.  I would stick with a chrome lined 16".  If you do decide to go with a 14.5", I would buy a Bushmaster 14.5" M4 with permanent Phantom from PK Firearms.   4)  Whatever stock you decide on, make sure it uses the milspec buffer tube.  Stag, Colt, LMT are the only companies I can think of that sell complete stocks with the milspec buffer tube.  You need the mil-spec tube if you later want to change out the stock for a Magpul, VLTOR or other replacement.  If you buy a non-milspec stock (RRA, DPMS), you will end up having to buy a new buffer tube in order to replace the stock.

I've been shooting irons and optics all my life,  I've probably sent 5 or 6,000 rounds down range out of AR's, just never my own, had AK's and some other stuff.  So I'm not a total n00b. but pretty new lol.  I'm not looking to build a replica of anything, just a fairly simple, reliable weapon.  Didn't know that about the stocks and being milspec.  


I appreciate all the help ya'll.  It's kind of intimidating once you start ordering parts.  I didn't anticipate needing this much help.

i second to look at another brand of a LPK--my DPMS LPK, while functional, was missing a selector spring and the fit of 2 of the pins was wrong on my MEGA (they required some filing and crushing), and the finish is a grey color, contrasting to the dark, rich black finish of the MEGA

i would instead recommend a RRA, Stag, or Armalite LPK over the DPMS for overall fit, finish, and parts quality and count

CMMG or Bushmaster or eaglefirearms.net cut 14.5+perm vortex would work for a fair price; i prefer the phantom for its closed ports and no tunning fork noise when i shoot, but the vtex is great at hiding flash!

a Stag/CMT BCG is another good one for the price

LMT--the SOMPOD or M4 stock?;
if m4 stock, then Stag also has milspec and are nice for the money; DSGarms, eaglefirearms, mooneys, and rainier arms, etc in the EE would have the best prices

a std FSB would work; if you want a fold down, the PRI is tops for the money, as are GGGZ's and the budget minded one from YHM
if you would just prefer a flat or low-pro gas block (then but flip down front BUISs on the rail or block), then one from YHM or dpms is good

the cheaper, solid BUISs are: ARMS 40(L), KAC, YHM, and GGGZ's A2; troys around here are more recommended, but they cost more
BUIS thread

gas tube length, well get the one that fits your bbl gas length--CAR, middy, or rifle; 14.5in bbls are usually CAR, but a few (like from CMMG and custom cuts) are middy nowadays

what kinda 4 railed handguard? FF or slip ones? Railed HGs thread

for the money, MI is great for the price, fit and finish; YHM, some of surefire's (M73) are also good for under $200; the more expensive ones, LaRue, KAC, DD are also nice, but very pricey

the TG's VFGs have more girth, grip, and feel, and i like em over the std KAC-styles; but then, i dont like VFGs much

well, it would be best to have the 14.5in bbl w/ the perm attached FH, but unless the ATF hits your door while you have it, get it perm installed ASAP; some places wont sell sub-16in bbls to non-NFA off the bat, so it will matter on em too

a std m7/m9 bayo will work w/ the vortex; these bayos will work w/ a 14.5+perm FH on a CAR system, a 16in (w/ or w/out FH) middy, and a 20in rifle length

Mags FAQ--best i can recommend and like: british steel, USGI aluminum mags by labelle, DH, okay, and sanchez--check the EE and industry board (bravocompanyusa, 44mag,etc) for the best deals on USGI mags for ~$10

$500 for all of this is stretching it; its possible, IF you scour the EE for used stuff

one other not: READ, READ, read--esp the tacked threads mr dusty

Plus 1 to above on reading as much as possible. I would also check out the EE for Good quality used stuff Like the Stock. For barrels I would probley rec. Going with 16in over the 14.5 to start. Bushmaster makes a nice 1/9 mock M4 barrel. Also CMMG makes 14.5 with permintly attached F/H but in 1/7 and with M4 cuts. For the Money unless you alredey have a upper look at the CMT. Very nice and you can get them with or without M4 cuts. I think your first buld should go Kiss. So I would spend the money on the barrel and a Quality M/P tested bolt from CMT or LMT. And hold of on the FF handgards. Get a good set of COLT M4 double heat sheald from the EE. Spend the Money on what counts. LPK. Several Good one's out there check out Rainer arms. Once you get it together and have a chance to play with it. Then let the Moding begin. I would look at the DD or Larue FF rail. As a later  upgrade. But in the end its your money and Toy. So enjoy and keep us posted.