PDA

View Full Version : Building an Upper


Prc329
12-01-2006, 8:00 AM
I was looking threw the arf.com do it yourself forum when I cam to the conclusion I would like to build an upper myself. One question I can't seem to find the answer to is what all will I need.

Here is what I think.

Upper
Barrel
gas block
gas tube
handguard
bolt
charging handle.

What am I missing besides a few tools I may need? Is there any other internal parts I need?

SemiAutoSam
12-01-2006, 8:02 AM
Front sight or Scope

BoltCarrier

Prc329
12-01-2006, 8:22 AM
I didn't list sights because I haven't decided which way to go.

Thx.

mltrading
12-01-2006, 9:06 AM
Gas tube pin.
Muzzle device (uncessary if your BBL is not threaded).
Action block or receiver claw for upper receiver.
Barrel vise.
If you are going to install traditional HG, don't forget the small parts like snap ring and delta ring. If you are going free-float forearm, remember to get a proper forearm wrench.

Prc329
12-01-2006, 9:08 AM
Would an armorer's tool work?

mltrading
12-01-2006, 9:10 AM
Would an armorer's tool work?

Regarding to FF forearm? Might be just fine.

mike452
12-01-2006, 9:15 AM
Would an armorer's tool work?

for HG ok, but not for barrel.

SquidBeak
12-01-2006, 8:00 PM
Are you going to start with a totally stripped upper?

Prc329
12-01-2006, 8:37 PM
Thinking about doing it that way.

Prc329
12-01-2006, 9:28 PM
http://www.bushmaster.com/shopping/gunsmith/1570.asp

That is the wrench i have.

Tzvia
12-01-2006, 9:59 PM
The USGI wrench is nice and simple, but it won't fit around a fat varmint barrel. I have both the bushy and the USGI and they both have there place.

The most important things to have are a good clean well lit workspace, a solid bench vise to clamp the action block in, and TIME. Do not rush anything. You could do something dumb like put the muzzle brake on, then realize you need to take it back off because you need to get the gas block on DOH.:o

Oh, in case nobody mentioned, barrel vise blocks (for putting the muzzle brake on). You can't use the action block to hold it steady and torque the muzzle brake, you can strip that locator pin in the barrel that way.

Also a torque wrench, and I also use a breaker bar (or cheater bar as my dad would say) to tighten the barrel nut. It allows me to watch carefully and move that nut right into place on the next hole after 30ft lbs without jumping up and down on it like a monkee.

It sounds harder to do than it is. I bought my first Ar type rifle in Feb (Carbon 15) and built my first upper in April. The instructions on Arfcom are very good IMO. I keep a copy at the workbench.

NeoWeird
12-01-2006, 10:00 PM
When I installed my barrel I put some bearing grease on the threads and put the nut down as tight as I could by hand (which is a ***** with the delta ring assembly in the way). I compressed the delta ring and I was able to turn it several more times by hand until the thing nearly bottomed out. After that I had to turn it another degree or so to line up and at that point no additional torque would turn it with my armoror's wrench. If you think about it, the only way the thing is comming off is if it backs off from vibrations, but with the gas tube in the way it won't be able to back off more than a degree or so. It's not like it has to be torqued down, you just want no slope in the thing. From what I have heard on arf, you want it on as hard as it needs to go to index past hand tight. Make sure hand tight is hand tight though, and not just a nick, piece of dirt, etc in the threads.

I also installed my handguards with a screw driver (put the front of the handguard into the retaining ring, then depress the delta ring and carefully wedge the screwdriver under the rear of the handguards and the delta ring. With a little upward pressre the screw driver should depress the delta ring just a little bit more at which point you can slide the handguard right in. The bottom one caught on the edge as it was going in and marred it slightly, but not anywhere that you can now that it is installed. No need for a $15-30 tool for just that, YMMV.

adamsreeftank
12-02-2006, 12:01 AM
You can install the barrel without a torque wrench, but it will save you a lot of guess work if you have one.

A very good book on building ARs says to tighen it to 30 ft/lbs and loosen three times, then go to 35 ft/lbs. Then keep increasing in 5 ft/lbs increments until the holes line up for the gas tube. If you are installing a free-float tube, you might need to put a lot of torque on it to get it lined up. When I installed a standar setup, it was about 45 ft/lbs. When I installed a LaRue FF tube, it took 85 ft/lbs to get things lined up.

I don't know why people have trouble installing the plastic hand guards. If you stand the rifle up on its stock and put the top of the handguard in the retainer, you should be able to press down on the delta ring with your hand and get the handguard in. The tool is nice if you are servicing a rack full of rifles, but not neccessary.

SquidBeak
12-02-2006, 12:37 AM
One of these or something like it may not be a bad idea: http://www.booktrail.com/Video_Shooting/AR-15%20Armorer's%20Course.asp

Tzvia
12-02-2006, 7:20 AM
I also installed my handguards with a screw driver (put the front of the handguard into the retaining ring, then depress the delta ring and carefully wedge the screwdriver under the rear of the handguards and the delta ring. With a little upward pressre the screw driver should depress the delta ring just a little bit more at which point you can slide the handguard right in. The bottom one caught on the edge as it was going in and marred it slightly, but not anywhere that you can now that it is installed. No need for a $15-30 tool for just that, YMMV.

LOL I installed handguards once with a strong rubber band. Hooked the upper part in the triangle, slipped a very tight thick rubber band on the handguard down low by the delta, held the rifle straight up on a solid surface and pushed down on the delta... Snap! The rubber band pulled the handguards together. I simply made sure they were in place, and let go of the delta.:D Did not think it would work but it did.