MachIVshooter
Member
This was an interesting project. Obviously we all know that AR's can be built under 5 lbs, but we also know that lightweight components don't come cheap. My goal was to see if I could get under 5 lbs for under $500. I succeeded.
Yes, I know, if you don't have machining capabilities, this is not doable. I still thought everyone would find it interesting.
It started out with an Ares polymer lower, which a friend of mine bought on sale for $50 with his two billets. He changed his mind about doing a polymer build, though, so gave it to me. I'm counting $50 +$10 S&H he paid, although I actually did not pay for it. He gave it to me as a thank you for letting him use my machines to finish his other lowers, back before ATF 2015-1.
Anyway, I finished it out, but it's been just sitting on my shelf for the last 6 months, waiting for me to decide what to do with it. Last week I decided to start making some LW parts, and the ball got rolling. First was the selector; not modified, but carved out of a hunk of 2219-T6. Remember: A standard selector weighs 17 grams:
That was the motivation I needed. That night I hopped on JSE and ordered up a barrel, gas tube and stripped upper. I was originally going to mill off the FA and dust cover provisions, but then my friend/neighbor/SOT FFL told me he had natural finish Aero Precision LW uppers on hand for $40, so I just grabbed one of those instead. I went with a cheapie fleabay hand guard and aluminum gas block. I am actually fairly pleased with the quality fo the $60 FF keymod guard, although I will switch to a MI or BCM later to shave another 3-4 ounces. But those did not fit my sub-$500 parameter for the initial build, so the advertised 10.2 oz (10.9 on my scale) ebay special is what we're rockin' for the time being.
Anyhow, the barrel showed up yesterday, so I went to town. First I carved 19 grams (2/3 oz) off the upper and 74 grams (2.6 oz) off the bolt carrier:
Then we turned the M4 profile barrel down to .540" both fore and aft of the gas block, taking it from 25.2 oz to 20.1 oz (sorry, no before and after pics there). Last piece of the puzzle was the 2.3" brake to get my 16" title I length. The brake is machined from 6/4 Ti and pinned. Instead of welding and discoloring the Ti, I took a different approach: drilled and tapped the brake #10-32 at the 6 O'clock position, installed it, marked the barrel, removed the brake, spot drilled the barrel .100" with a 3/16" end mill, reinstalled the comp, slobbered the stainless 10-32 socket head with red Loctiite, cranked on the screw in until the head stripped, then cut it off and ground it smooth. You can see it, but pretty much need to be looking for it.
So, the build list is:
-Ares polymer lower: $60 shipped on sale
-PSA Blackhawk LBK: $84 shipped on sale
-Areo Precision raw LW upper: $40 local
-DSA BCG & CH: $89 shipped
-1:9 Chromoly barrel from JSE: $95
-Carbine gas tube: $10
-JSE shipping: $10
-10" FF Keymod hand guard: $60 shipped on the bay
-alumium gas block: $8 shipped ebay
-cheapie flip-up sights: $16 ebay critters
-2.3" piece of 6Al-4V Titanium for the comp: ~$5 (11" piece was $30 shipped)
So that's it! We'll see how she runs today. It still has a standard 3 oz buffer in it, but I'm taking one with me that has no weights to see if it'll run that way. I still plan to do a hybrid aluminum and tool steel trigger as well, but didn't get that far yet.
Yes, I know, if you don't have machining capabilities, this is not doable. I still thought everyone would find it interesting.
It started out with an Ares polymer lower, which a friend of mine bought on sale for $50 with his two billets. He changed his mind about doing a polymer build, though, so gave it to me. I'm counting $50 +$10 S&H he paid, although I actually did not pay for it. He gave it to me as a thank you for letting him use my machines to finish his other lowers, back before ATF 2015-1.
Anyway, I finished it out, but it's been just sitting on my shelf for the last 6 months, waiting for me to decide what to do with it. Last week I decided to start making some LW parts, and the ball got rolling. First was the selector; not modified, but carved out of a hunk of 2219-T6. Remember: A standard selector weighs 17 grams:
That was the motivation I needed. That night I hopped on JSE and ordered up a barrel, gas tube and stripped upper. I was originally going to mill off the FA and dust cover provisions, but then my friend/neighbor/SOT FFL told me he had natural finish Aero Precision LW uppers on hand for $40, so I just grabbed one of those instead. I went with a cheapie fleabay hand guard and aluminum gas block. I am actually fairly pleased with the quality fo the $60 FF keymod guard, although I will switch to a MI or BCM later to shave another 3-4 ounces. But those did not fit my sub-$500 parameter for the initial build, so the advertised 10.2 oz (10.9 on my scale) ebay special is what we're rockin' for the time being.
Anyhow, the barrel showed up yesterday, so I went to town. First I carved 19 grams (2/3 oz) off the upper and 74 grams (2.6 oz) off the bolt carrier:
Then we turned the M4 profile barrel down to .540" both fore and aft of the gas block, taking it from 25.2 oz to 20.1 oz (sorry, no before and after pics there). Last piece of the puzzle was the 2.3" brake to get my 16" title I length. The brake is machined from 6/4 Ti and pinned. Instead of welding and discoloring the Ti, I took a different approach: drilled and tapped the brake #10-32 at the 6 O'clock position, installed it, marked the barrel, removed the brake, spot drilled the barrel .100" with a 3/16" end mill, reinstalled the comp, slobbered the stainless 10-32 socket head with red Loctiite, cranked on the screw in until the head stripped, then cut it off and ground it smooth. You can see it, but pretty much need to be looking for it.
So, the build list is:
-Ares polymer lower: $60 shipped on sale
-PSA Blackhawk LBK: $84 shipped on sale
-Areo Precision raw LW upper: $40 local
-DSA BCG & CH: $89 shipped
-1:9 Chromoly barrel from JSE: $95
-Carbine gas tube: $10
-JSE shipping: $10
-10" FF Keymod hand guard: $60 shipped on the bay
-alumium gas block: $8 shipped ebay
-cheapie flip-up sights: $16 ebay critters
-2.3" piece of 6Al-4V Titanium for the comp: ~$5 (11" piece was $30 shipped)
So that's it! We'll see how she runs today. It still has a standard 3 oz buffer in it, but I'm taking one with me that has no weights to see if it'll run that way. I still plan to do a hybrid aluminum and tool steel trigger as well, but didn't get that far yet.