Build Thread Building my first ar pistol

[Zerocool]

Hey guys. Building my first ar pistol.
Here are the parts I'm working with:

M4e1 stripped lower with M4e1 lower parts kits
M4e1 assembled upper receiver with forward assist and is threaded one not the enhanced one
Ballistics advantage 10.3" barrel
Going to buy the atlas s-one rail

anyone ever do a build like this? Any suggestions or advice?

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[Zerocool]

On the lower take down pin spring below do I need to cut that?

 

[Zerocool]

Got some questions on these parts if anyone has done an M4e1 before

 

[Nosferatu]

Assemble away, it's not rocket surgery.

If you have specific questions, ask.

 

[Kruel J]

Looks like a basic AR build. YouTube has many good videos on assembling the lower.

 

[sithc]

On the lower take down pin spring below do I need to cut that?

No, don't cut. It shouldn't need to.

Like Nosferatu said, it's not hard. There's a YouTube install video for just about every item.

I'm in Tigard as well if you need help or missing a small part.

 

[DirectDrive]

On the lower take down pin spring below do I need to cut that?

The AP lower uses a 4-40 set screw to capture the takedown spring as you may know.
Sometimes the set screw is supplied, sometimes not.
It's a convenience thing and the rifle was designed to assemble without it.
I use the set screw and in theory you're supposed to cut a piece off of the spring equal to the length of the set screw.

I didn't cut mine and it works.
Try it without cutting and verify that it operates smoothly with no bind.
I also put a little grease into all "detent tracks" and that seems to help them operate smoothly.

 

[DirectDrive]

Got some questions on these parts if anyone has done an M4e1 before

Click to enlarge

 

[sithc]

I used install the pivot pin manually and it was a pain. I now use this and it takes 15 seconds as opposed to lots of frustration and loss springs shooting out. I can swing by with it if you can't install yours.

Amazon.com : Real Avid Pivot Pin Tool (AVAR15PPT), Red : Sports & Outdoors

Amazon.com : Real Avid Pivot Pin Tool (AVAR15PPT), Red : Sports & Outdoors

www.amazon.com

 

[DirectDrive]

I believe this series to be the best (free) AR 15 Build videos on the Web.
Professionally done, 11 sections.
Watch them in order.

Trigger Times | Brownells

Trigger Times | Brownells

www.brownells.com

 

[DirectDrive]

I used install the pivot pin manually and it was a pain. I now use this and it takes 15 seconds as opposed to lots of frustration and loss springs shooting out. I can swing by with it if you can't install yours.

Amazon.com : Real Avid Pivot Pin Tool (AVAR15PPT), Red : Sports & Outdoors

Amazon.com : Real Avid Pivot Pin Tool (AVAR15PPT), Red : Sports & Outdoors

www.amazon.com

View attachment 1000027

I use the "Hitch Pin Method"
This uses a common, hardware store 1/4" diameter hitch pin.

 

[Zerocool]

I got the pivot pin in and the magazine catch so far

 

[Zerocool]

My lower parts kit didn't come with a pistol grip lock washer.

 

[DirectDrive]

My lower parts kit didn't come with a pistol grip lock washer.

They (star lock washer) are easy to find at a full service hardware store.
Bring your grip screw to get the right size.
It's 1/4 -28 if you forget it.

 

[Kruel J]

A drop of blue loctite works too.

 

[Zerocool]

Do I add blue loctite to the bolt catch set screw?

 

[DirectDrive]

One thing to check before you jump in is the bolt catch pin hole.
I think on the lower you have, that hole is threaded.
If so, it should have come with a special set screw and it is often temporarily installed in the hole for safe keeping.

If it's threaded, and no special set screw, email A-P and ask for one.

 

[Zerocool]

It came with one already in it

 

[DirectDrive]

Do I add blue loctite to the bolt catch set screw?

I would.
Being a new builder, I'd use Blue just in case I put something in upside down.
The take-apart would be brutal with Red.

 

[DirectDrive]

It came with one already in it

View attachment 1000043

A-P did a nice job designing your lower.
With that particular lower, you escape what I call the two "Man-Boy" separators in an AR build.

1) The trigger guard roll pin.
Many sob stories of broken ears.
Yours is integral.

2) Bolt Catch Roll Pin
This is another tricky pin to drive.
There is actually a How-To video on the Web where the guy mashes (folds over) the end of the pin and calls it good.
Others show the Plier Method and some scar up their lower doing that.
Yours is threaded, so no roll pin to drive.

I was s******n' bricks the first time I drove those pins.