Hi all,
I had a fun time with this project. I wanted to make a second attempt at building a very light-weight AR15. At the same time, I have a friend that I have enticed into the cult of the Evil Black Rifle, and I set this project up as a build-it-yourself class. Thought I'd document what it looks like for anyone that wanders by the BIY forum.
What's cool about this project is that I held-off assembling any parts until today. So the entire project from parts to rifle was about 2 1/2 hours, including problems and finishing touches.
At 10:00am this morning it looked like this:
Tools ready in the kitchen for building the lower:
Here's the garage workbench ready to assemble the upper:
We're off! Eagle Arms lower gets a trigger guard and magazine catch:
Had some trouble with the roll pin for the bolt catch. I think I should have wiped it with oil before I began, because it didn't want to go the last .001". Got it in and flush but not without losing the blueing on the pin, which fixed-up with cold blue later.
Also ran into a very strange problem with the pivot detent spring hole. It was drilled too deep. I had to cut a tiny length of coat hanger wire and drop it in the hole to bring the spring and detent up to where adequate pressure was put on the pivot pin. Very wierd, but it worked fine:
Smoothed the sear surface of the trigger with 400 grit emery before installation. Trigger went in, though it took forever to get the pin to line-up with the disconnector:
Polished the hammer, installed no problem:
Ace Ultralight stock finished off the lower, piece of cake:
Function tested the lower, everything works great. Now on to the upper.
I chose a Vulcan Arms carbon/Aramid flat-top upper receiver because it's extremely light and looks cool with no forward assist or ejection port cover. Also very cheap. But in test assembling it the day before I found the fit to the Bushmaster superlight barrel was loose. I cut a wrap-around shim (soda can aluminum) to go on the barrel extension, full width from the shoulder to the edge near the lugs, and completely enclosing the barrel extension. I also had to make a micro-tiny shim to wrap the index pin. Now it's snug:
Delta ring, weld spring, snap ring, and a 3/16" rod to keep the gaps lined-up:
I went easy on the barrel nut, because I really don't know what to expect from the carbon/Aramid and I'm paranoid that I could strip it if I honked on the wrench. I will need to watch this when I test fire it. Gas tube lined-up, tested with the bolt, nice and centered. Gas tube pin went in very quickly:
Almost done! Topped the receiver with an ARMS #38 standard-length Swan sleeve. I was going to do just a #40 back-up sight, but in trying the flattop with the OKO, the red dot was in the middle of the front sight pin. I found this distracting. The #38 rail gets the red dot up above the pin:
OKO goes on top and we're done. I don't have an accurate low-weight scale, so I did the hold-it-put-it-down-a-few-times method with the bathroom scale and I think its a little under 5 pounds. Here's the finished product:
Now that wasn't hard, was it?
Specs:- Eagle Arms stripped lower (Quantico)
- Vulcan Arms Carbon/Aramid stripped flattop upper (Vulcan Arms)
- Rock River Arms lower parts kit and charge handle (Georgia Precision)
- Rock River Arms bolt, bolt carrier (Eagle Firearms)
- Ace Ultralight stock (Del-Ton)
- Bushmaster superlight 16" post-ban barrel kit (Eagle Firearms)
- ARMS #38 standard-length Swan sleeve (Eagle Firearms)
- OKO red dot sight (Brownell's)
C_M
RANGE REPORTI finally made it out to the range. It was a great day, nice weather, and I had DPRC to myself. I shoot on the 50 yard range because I'm too lazy to walk far.
I fired 100 rounds of Lake City (Federal) 55gr. and 100 rounds Wolf 62 gr. Used four different 30-rd USGI and one 20-rd USGI. The Lake city was fired first for sighting-in, then the Wolf for rapid fire (thirty followed by twenty).
Results: No failures to feed or eject, no jams of any kind, last round bolt-hold-open worked every time! 100% functional in every respect.
This rifle ROCKS! My kids would say
SHWEET! It handles like a baton, has good accuracy and is a blast to shoot.
I did a careful cleaning afterward and find no indication that the Vulcan Carbon/Aramid upper will have any problems. I ran the carbine up hot so that smoke was pouring up around the FSB, but it didn't seem to bother it. What's better, the upper proved extremely easy to clean, all the grit wiped off with a shop rag, and it looked like new on the inside (except around the gas tube, of course.)
The sights worked GREAT. The OKO sight is up in the clear, about 1/2 inch higher than normal. When the dot is centered in the sight its about 1/4" above the sight pin. And the ARMS sight worked great. If I was going to be a purist (like
Tyrod ) I could have done the gas block thing and ditched the ARMS #38 and shaved off some ounces, but I like having both the red dot and the iron sights.
Only two odd things about the rifle: the rear sight is about 1 mark to the right of center, and it drops brass about 5 o'clock behind me. Hardly worth mentioning.
C_M