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View Full Version : 80% Receiver Build #2


m4forme
07-28-12, 08:16
Fired up the mill yesterday and whipped out a 80% lower...

Going to be a A2 build with a Colt 1/7 HBAR barrel...

Took my time and fit the upper and lower so there is no play between the upper and lower...

Very slow process .001 out of the receiver pocket at a time untill it fit just right...

But I'm picky and have the patience of the Pope...

I'll post more as the build continues...
SpankMonkey
07-28-12, 08:45
Nice. Keep us posted.
MistWolf
07-28-12, 10:49
Very cool! That's a project I'd like to tackle someday but currently, I don't have the space or the money for the machine tools
far9mm
07-28-12, 13:29
Very nice! I build one a few weeks ago using a drill press! Took 6 and half hours but it's turned out great. Wish I had a cnc mill! Yours looks great!
Cesiumsponge
07-28-12, 15:32
How tight are the tolerances on finishing operations to complete a forging? I've always considered the idea of whipping up some G-code and doing it on a CNC center in my spare time since workflow at my company is winding down.

Do the businesses that sell these 80%ers send instructions and prints, or is that up to the end-user to track down?
m4forme
07-28-12, 16:27
kind of wing it...

Plus the jig i have helps alot!!!

I have a set of prints i use to check as i go...

Made a few mistakes on the first one that i resolved on #2

#1 is used with a Ceiner .22 kit and a beater upper & a Colt SP1 upper for .556

It's got 5000+ rounds through it of .556 & ,22lr and still going strong...

You might do well making 80% loweres if you have access to a CNC Mill...

I know Tactacal Machining has been out of AR-15 lowers fo a while now...

The lowers i received from them had the Cerro Forge mark on them...

Remington has that new M4 contract they may be taking them all...

I just got a Quintin Defence 80% Billit lower that is for #3 it's SWEET thats what I'd make if i had CNC equipment...

I'll be picking up a few more of those soon...
far9mm
07-28-12, 16:52
Check out cncguns.com they have all the plans and software if you have cnc.
m4forme
10-03-12, 14:53
turned out real well...

got a smoking deal on a Colt M-16 A2 upper...

I'll use the A2 HBAR upper for a billit lower that i'll do for a winter project...

I sand blasted the lower a little and finished it with KG Gunkote flat black bake on moly resin...

It was almost a perfect build except when i was doing my finish cut on the bottom of the trigger pocket...

I didn't lock the the head of my mill and it fell through making the trigger hole a little out of shape...

I won't make that mistake again!!!

But all in all it turned out very well...
sevin8nin
10-03-12, 22:35
Looks clean.

I'm curious, on the ATF side of things, when do you have to serialize/engrave the lower? Does it go on a form 1?
deviljon
10-03-12, 22:40
Looks clean.

I'm curious, on the ATF side of things, when do you have to serialize/engrave the lower? Does it go on a form 1?

In Cali, it only needs to be serialized when you're doing a sale/transfer. If its for personal use there's no need.
sevin8nin
10-04-12, 02:35
In Cali, it only needs to be serialized when you're doing a sale/transfer. If its for personal use there's no need.

Very cool, makes it easy for you!
KrampusArms
10-04-12, 02:41
I love the look of that blank lower. Totally cool man. Thanks for the pics.