AR-15 BS Thread

I have no armorer's tool nor do I know what that is, but if I was to guess I'd say it's that funky looking wrench with the handle that's keyed for the castle nut? I've got some punches and screwdrivers though haha.

 

You should be fine then. I eventually bought an armorers wrench after building my 3rd AR...haha I kinda needed one. I got mine from palmetto state armory for like 20-25 bucks.

 

Ya.. If you're careful, you can handle the lower assembly and castle nut with a punch and a hammer, but assembling the upper? You aren't getting 80ft/lbs on the barrel nut without the proper tool.

http://www.cdnninvestments.com/arsutomiblta.html

 

That's a good investment, I'll get one soon enough. This is my first AR.

And as for the barrel wrench....also a good investment. The upper I ordered already comes with the barrel installed, headspaced, and test fired though..

 

Yep. You are good to go for now. I had a standard front sight post I wanted replaced with free float rails. So I got the wrench that has the castle nut, barrel nut, flash hider wrench all in one.

Now go have some fun

 

This might be a silly question..... I've read about free floating barrels and rails before although I really have no experience......but is the upper I ordered a free floating barrel and rail?

 

Yes. That's why it cost so much more than just their standard mid length upper (400$)
The barrel and handgaurds are only attached at one point, at the receiver.

 

Check out m4carbine.net

Tons of great info over there

 

Free float doesn't refer to the barrel, it refers to the rail... it simply means that the handguard/rail/tube is only attached at the receiver or barrel nut.
This cleans up the barrel harmonics because there is nothing attached to the barrel at the midpoint.

 

Thanks for the info dudes. I'm far too excited for these parts to come in.

 

Free float means the barrel does not touch anything other than where it attaches to the receiver. Bolt guns where free floated long before AR's
But yes, you are correct in terms for the AR.

I just didn't want anyone to get confused

 

Well... you've got the gas block, but the gas tube is floating on the receiver end.

But that does bring to mind the issue of barrel harmonics on a piston upper.

 

It has some effect, but in some systems (LWRCI) the bullet has just left the barrel when the systems just starts to engage so there is almost no effect on barrel harmonics. Here is a video of it in slow mo showing the operation, over and over. My M6A3 DMR puts up sub moa groups without even trying.

http://www.youtube.com/watch?v=wECpY9MVZI4


Also keep in mind my system is the stretch system which has the piston block closer to the muzzle. If it was carbine length or pistol length but same length barrel I would imagine there being a much larger effect from barrel harmonics.

 

Need range time! lol

 

I finished it today! (for now anyway.....)

 

sweet looking. Planning any optics for it or staying with iron?

 

I'm eventually planning on optics, I'd like to become proficient with the irons first.

 

hence, co-witnessing.

 

I agree with you. That and the optics can't be afforded right now

 

Almost done.
Spikes lower, 16" PSA upper, Magpul furniture, Troy TRX handguard.



I am waiting for some Troy iron sights.