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Building your own AR

Chuck

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How about a sticky with info and links on what you need to build-up your own AR15 from a receiver. There ah, just may, be a WHOLE bunch of newbies around here getting into AR building soon!

I'm heading to Marlborough's gun show tomorrow (Sat), what unusual tools and/or parts should I keep my eye out for?

-= chuck
 
If you're building from a stripped lower, you're going to want a barrel wrench and a good set of punches with concave heads. Also handy, as I have read, is a magazine block (not sure if thats what its called) to go into the mag well when you're working on the rifle. You can use it to clamp a vise onto, and also I think it is supposed to protect the internals if you accidentally drop the hammer without an upper installed.
 
The two best (as far as making life easy) tools for AR Assembly are the pivot pin tool (which you can make out of a 1/4" clevis pin) and the special punch made to install the BHO pin. Other than those two tools all you really need is a set of drift punches
 
The two best (as far as making life easy) tools for AR Assembly are the pivot pin tool (which you can make out of a 1/4" clevis pin) and the special punch made to install the BHO pin. Other than those two tools all you really need is a set of drift punches

I made up a pivot pin tool but found I preferred the removeable pin. What is a BHO pin? I've built three ARs and haven't got a clue.
 
I made up a pivot pin tool but found I preferred the removeable pin.

I made one also. Just the same I'd still recommend installing the pivot pin detent and spring while in the bathtub with the curtains/door closed and something to cover the drain with.

What is a BHO pin? I've built three ARs and haven't got a clue.[/QUOTE]

BHO = bolt hold open... otherwise known as the magazine catch/release.

Pin = roll pin/split pin.
 
BHO - I'm going to guess he's referring to the Bolt Catch. The roll pin used to hold that can be tricky for some to install because it is difficult to use a standard length punch. There are ways around that though.

Here is a great guide to assembling an AR.
Building an AR
 
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BHO - I'm going to guess he's referring to the Bolt Catch. The roll pin used to hold that can be tricky for some to install because it is difficult to use a standard length punch. There are ways around that though.

Dohhh... I just reread what I posted. [thinking]
 
Yes, the BHO/bolt hold open/bolt catch pin is what I was referring to.
They make a punch designed specifically for that pin. It's longer than normal and flat sided to clear the mag well. Makes life real easy and prevents scratching the receiver
 
So i think I decided on a RRA upper for the lower already ordered in the group buy.
I want a nice target rifle that has great accuracy.

What do you guys think of this model:

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Standard A4 Upper Half; Quad Rail Lightweight Free Float, $160.00 option; Stainless Steel, 1:8, $65.00 option; A2 Front Sight; A2 Flash Hider; With Standard Latch

The quad rail lightweight free float is:

hgrdqdlw.gif


or should I go with : 20 Inch Predator Pursuit Upper Half

upredp07.gif
 
If you are in MA, you can't use a "Flash Hider" on the group buy lower. It's not allowed by the MA AWB. Get it with a compensator (permanently attached) or better a match grade crown and you will be fine with the top ones.

Twist will have more to do with what you intend to shoot. The heavier the bullet, the more twist you need. 1:8 is generally good for the 62 grain match bullets. 1:7 is for 70+ or SS109 military. 1:9 for lighter plinking rounds. If you don't know what you will be shooting, I'd go with the 1:8 as it will work with just about anything.

Handguards are a personal choice. Nothing wrong with a standard A2 set until you can decide what you need. As with a wood stock, a free floating barrel usually provides the best accuracy. In the AR platform, that means a free floating handguard that only attaches at the rear and otherwise does not touch anything. These have to be rigid, especially if you intend to sling up on them or use a bipod. I have not decided what setup I will use, but a free floating is a desired feature.

As for the last choice you offered, it's a choice you need to make. It's not a bad choice, just be sure it suits your needs. Is that fancy expensive handguard going to be swapped out for something with rails? Can a bipod be attached if that's something you want? Is the sight rail on the gas block a good thing? ie, are you going to mount iron sights? Would a lower profile gas block look better to you?

The Wylde Chamber is a nice feature as it's a little snugger than the NATO chamber, but can still fire NATO ammo.

Your best bet is to decide what you want to use the rifle for and then build it for that purpose. Your best bet for a 'first' is a straight standard A2 style upper (without the flash hider) so you can have something to play with. Then, as you find your preferred shooting, build a custom upper for that purpose.

For me, I have a Colt AR that I'm leaving in the factory A2 configuration and my new lower will be for a scoped precision rifle. But if I had not already played with the 'stock' rifle, I don't know if I'd really know which way to go.

Of course the top feature of an AR is the fact that you can swap out uppers to fit the situation.
 
As Chris said, it really depends on what you'll be doing with it.

Since you mentioned target rifle & accuracy, Free Float the barrel. Then the question is. Do you want to hang things off of it?(lights, fvg, etc.) That's what the quad-rail is for. If not, the free float design on the predator is a better choice. You won't need to get rail covers for rails you won't be using.

If you're considering shooting CMP service rifle matches all the big manufacturers make an upper that looks like a standard service rifle but has a free floated match barrel. I have one from Bushmaster & one from RRA, both shoot up to 77gr great & they are 1:8 twist each.

If you're going to put optics on it & the above were my choices, I'd pick the Predator.

Just my .02

CD
 
Thanks for the great input Chris and Cdkayak .... my intended shooting would be for 200-300 yard range. I intend it to be a target/match shooter more then a tactical configuration. I do expect to mount optics but also have a flip down set of sights on it .

I definetely need to do more leg work on the gas block aspect of these configurations as I still don't quite understand the differences.

"in MA, you can't use a "Flash Hider" on the group buy lower. It's not allowed by the MA AWB. Get it with a compensator (permanently attached) "

If I went with the predator this whole issue is void correct
 
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It's void only in that the predator upper out of the box has nothing on the barrel. If you ever did want to add something to the barrel the AWB restrictions would still apply. Good luck on your choices.
 
Thanks for the great input Chris and Cdkayak .... my intended shooting would be for 200-300 yard range. I intend it to be a target/match shooter more then a tactical configuration. I do expect to mount optics but also have a flip down set of sights on it .

I definetely need to do more leg work on the gas block aspect of these configurations as I still don't quite understand the differences.

A regular gas block has the traditional looking front sight tower.

A low profile one doesn't have the sight tower. Some of the low profile ones are really nothing more than a standard A2 front sight with the tower ground off. Other low profile gas blocks will have a picatinny rail on top for mounting flip-up sights (like the Predator).

An AR can have a flat top receiver and A2 type front sight.
It looks strange because the sight is blocking the objective end of the scope. It doesn't matter though, at a certain magnification and above (I want to say 7x but I forget at the moment), the scope will "see through" the front sight... you won't even know it's there.

"in MA, you can't use a "Flash Hider" on the group buy lower. It's not allowed by the MA AWB. Get it with a compensator (permanently attached) "

If I went with the predator this whole issue is void correct

Yep. However if you decide on something with a permanently attached muzzle break you should decide what type of gas block you want before you have the brake attached. Otherwise if you want to replace the block at a later date, you'll have to grind the brake off and replace it with anew one.
 
I guess this is a good place for this question and I know it has been discussed before so I apologize, but...

Are there any restrictions on the purchasing and shipping of any AR parts other then the lower?
 
A regular gas block has the traditional looking front sight tower.

A low profile one doesn't have the sight tower. Some of the low profile ones are really nothing more than a standard A2 front sight with the tower ground off. Other low profile gas blocks will have a picatinny rail on top for mounting flip-up sights (like the Predator).

An AR can have a flat top receiver and A2 type front sight.
It looks strange because the sight is blocking the objective end of the scope. It doesn't matter though, at a certain magnification and above (I want to say 7x but I forget at the moment), the scope will "see through" the front sight... you won't even know it's there.



Yep. However if you decide on something with a permanently attached muzzle break you should decide what type of gas block you want before you have the brake attached. Otherwise if you want to replace the block at a later date, you'll have to grind the brake off and replace it with anew one.


Once again great information - I guess I would be leaning towards getting a low profile gas block. I am thinking of having front and rear flip down sights for when I don't have a scope mounted. Again this build would be for target/match shooting so I am thinking I may just drop the tactical rails and go for a Aluminum or Hogue Free Float Tube.
 
I assumed that you save $ by building it yourself.

When I go to Armalite's web site, the price of a stripped lower plus all the kits comes out to $344, which is the same price if you by the exact same L15B complete lower assembly.
 
You may not always save money by building, but you can assemble exactly what you want. It pays off when you cannot find the configuration you want fully assembled and you would then need to replace parts.

It also an excellent way to learn the AR platform.

ETA
You can also find many parts used or on sale which will help in the overall cost.
 
If you are in MA, you can't use a "Flash Hider" on the group buy lower. It's not allowed by the MA AWB. Get it with a compensator (permanently attached) or better a match grade crown and you will be fine with the top ones.
Top ones have a bayonet lug on them, which is also a MA no-no, no?
 
Once again great information - I guess I would be leaning towards getting a low profile gas block. I am thinking of having front and rear flip down sights for when I don't have a scope mounted. Again this build would be for target/match shooting so I am thinking I may just drop the tactical rails and go for a Aluminum or Hogue Free Float Tube.

Be careful. A "low profile" gas block will not necessarily have a rail to mount a front sight. You should specify a gas block with a rail.
 
Stripped Lower Preferences:

OK I missed the group lower buy and and in the market for a lower (or two). After I voted against Clinton in the '92 elections I took a drive with Windham ME and left Bushmaster with an AR and a couple of lowers that I have built up over the years. I have been very happy with my Bushmaster lowers and uppers but I have not done business with them in over a decade. I'm in the market for a few more lowers to put in the safe and have seen some disparaging comments about Bushmaster in the forum. What is the current preference and opinion on lower brands? Bushmaster, DPMS, Olympic, does it matter?

Ralph
 
Stripped Lower Preferences:

OK I missed the group lower buy and and in the market for a lower (or two). After I voted against Clinton in the '92 elections I took a drive with Windham ME and left Bushmaster with an AR and a couple of lowers that I have built up over the years. I have been very happy with my Bushmaster lowers and uppers but I have not done business with them in over a decade. I'm in the market for a few more lowers to put in the safe and have seen some disparaging comments about Bushmaster in the forum. What is the current preference and opinion on lower brands? Bushmaster, DPMS, Olympic, does it matter?

Ralph

Ralph stay away from all those that you mentioned. If you want highest quality go with a Colt, Noveske, LMT, LWRC. Other great companies are Stag, Anvil Arms, Spikes Tactical to name a few.


-DM-
 
Top ones have a bayonet lug on them, which is also a MA no-no, no?

30 seconds with a Dremel can remove that, but a Flash Hider is a wee more difficult to deal with.

I would have no problem ordering an upper with Bayonet and Grenade lugs so long as I planned to neuter it before fitting the upper to a lower.
 
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