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80% lower build

MikeD said:
VitSports6 said:
So what do you think the best route for re marking them? Break down an aluminum lower or are there any places for a good start measurement? Like the front hinge?
I'm going to remove the nubs on mine and see about measuring from one of my other lowers.
Thanks again for all your work!
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Found this while doing a quick search: http://arlower.ray-vin.com/ar15/

Chapter 3 on the holes: http://arlower.ray-vin.com/ar15/chapter03.pdf
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Great find! Thanks. :cool:
 
VitSports6 said:
I'm going to remove the nubs on mine and see about measuring from one of my other lowers.
Thanks again for all your work!
Click to expand...

You may not have to Vit. It may have just been an issue with mine.

I'd measure everything before grinding off any of the guide nubs because yours may be correctly placed.
 
John A. said:
VitSports6 said:
I'm going to remove the nubs on mine and see about measuring from one of my other lowers.
Thanks again for all your work!
Click to expand...

You may not have to Vit. It may have just been an issue with mine.

I'd measure everything before grinding off any of the guide nubs because yours may be correctly placed.
Click to expand...

I did a little measuring with one of my other lowers last night with some calipers, mine was like yours, but I couldn't get a great reference point.
 
Not sure who is doing a complete build - I am. I'm looking for bang for the buck while making some improvements over what I currently shoot.

I posted a Mossberg carbine barrel earlier and am okay with 4140 carbon steel - thought I'd found the same barrel for less and I did - $100 shipped! It looked like the Mossberg and had scant info on the website so i wrote them and got a quick response:

http://www.sportsmansguide.com/net/cb/1 ... x?a=606333 (item page)

From the site - 16" barrel, 1:7" RH twist rifling. Chambered in 5.56 NATO. Includes barrel extension. Barrel threaded for a flash hider.

From response to my questions (no mention of Mossberg made from me) "...176775 is manufactured by Mossburg. 4140 Carbon steel, .750 at gas port, M4 barrel extension, 1/2" X 28 TPI for threaded end, Gas port is .062" +/- .001". The gas block hole is pre drilled."

Right now I shoot a 1:9 on a DPMS and I have my eye on the same upper i have now - a smoothside that is really well built. Midway stocks them for $86. They also show up on the used market for $40-50. They make a nice flat top. Improvement #2 will be a free float hand guard - one piece at a time...
 
mingaa said:
Not sure who is doing a complete build - I am. I'm looking for bang for the buck while making some improvements over what I currently shoot.

I posted a Mossberg carbine barrel earlier and am okay with 4140 carbon steel - thought I'd found the same barrel for less and I did - $100 shipped! It looked like the Mossberg and had scant info on the website so i wrote them and got a quick response:

http://www.sportsmansguide.com/net/cb/1 ... x?a=606333 (item page)

From the site - 16" barrel, 1:7" RH twist rifling. Chambered in 5.56 NATO. Includes barrel extension. Barrel threaded for a flash hider.

From response to my questions (no mention of Mossberg made from me) "...176775 is manufactured by Mossburg. 4140 Carbon steel, .750 at gas port, M4 barrel extension, 1/2" X 28 TPI for threaded end, Gas port is .062" +/- .001". The gas block hole is pre drilled."

Right now I shoot a 1:9 on a DPMS and I have my eye on the same upper i have now - a smoothside that is really well built. Midway stocks them for $86. They also show up on the used market for $40-50. They make a nice flat top. Improvement #2 will be a free float hand guard - one piece at a time...
Click to expand...

Lol.. I wasn't going to do an entire build... since the AR I already have was built by me :D But since I've been thinking about having a second uppper (a light weight straight irons) ... it's turned into a build, go figure. Like you, I'm doing this completly on the cheap...

As for the uppper... I haven't been able to piece together the parts cheaper than theses guys at Blackthorne Products offer a complete M4 type upper already. They apparently use Mossberg barrels and for $269 it's a good deal. They don't come with a BCG or charging handel, but for now I plan on using the one I already have... so it's the best deal I can find for now. I haven't ordered it yet... but maybe very soon :cool:
 
That's a good price on that barrel. At least for the specs.

Palmetto State Armory has complete LPK's with grip listed for $39.99-$59.99 depending on if you get an OEM grip or Magpul grip.
 
I went with a partial LPK from Brownells ($20) as I already have 3 triggers laying around in my parts bin. Meant to start working on the lower last night but fell asleep at 8 o'clock... go figure!
 
I really want to do something other than 223 for my next build. Although ammo availability is becoming a real issue.
 
MikeD said:
I really want to do something other than 223 for my next build. Although ammo availability is becoming a real issue.
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I've been toying with the thought of doing a .22 upper... but .22 is even harder to find that .223 right now. Wallyworld has a whole pallet of M855 cases out... but for $500 a case I can't afford it.
 
Rep points for you John! Thanks a bunch for being the guineau pig for us and documenting the whole way... I know it'll help me a lot!
 
I'm about to wade into another session of material removal - the eyeball check vs another upper tells me to get out the calipers.

Oli - the PSA stripped upper ls really tempting - $7 to ship a cap for the forward assist (or parts kit) and dust cover. I may stick with my slickside. I have some cash but, erm, should lay off CC and bank account for now. If I don't find a used DPMS upper I can drive by Midway - there is a major reloading center on the way as well.

http://www.midwayusa.com/product/138383 ... -top-matte

My story so far (*is paid and here or in transit):
*Lower EPLOWERS $45
*CMMG LPK with Grip $60
*Stock / buffer system CDNN $50
*Barrel 16" The Sportsman's Guide $100

-Stripped Upper - DPMS slickside $95 ($50 used?)
-BCG AimSurplus - $100
http://www.aimsurplus.com/product.aspx?item=XAIMBCG
-Muzzle Brake + washer - ? ($15-20)
-Free Float Hand Guard - ? (2 rail minimum, over 7" covers gas block...)
-Charging Handle - ? ($20)
-Gas Block (fits under guard) - ($25)
-Gas Tube + pin ($15)
-Sights / Optics (unknown, possible in house to start)
-Magazines (in house)


SO - looks like if I budget $75 for a free float hand guard I'll be at the $600 mark AND I have the base $600 factory gun (DPMS Sportical) to compare it to. With the 1:7 barrel (vs 1:9) and a free float longer hand guard I mave have an edge if all systems play nice together. *fingers crossed*

I have mags and optics to get started but that's about it in the workshop. I like the AIM BCG on paper - anyone have experience with them - staked, tested, got a solid front (not over milled...).

Anything major I'm missing - like barrel nut $10 just hit me (crap!). Anything I'm budgeting too much for?

Full float hand guard recommendations - you know solid as a rock - 1 piece aluminum but $75 or lass! Longer than a 7" carbine is goal too - hehe! :D
 
Well the budget is really an arbitrary number. I can buy a DPMS Spotical at Walmart now for $615 + tax. My budget includes tax and shipping do that becomes $670 with tax It's just a bit of gaming - the real goal is a good gun ( or better) for a good price built by me and the learning that goes with that experience.

I'll check with PSA tomorrow and see if they will give me the discount with a mailed money order dated on the 31st. I've bought guns and more from them - bet I can make that happen. The Troy hand guard is really what I'm looking for - a big part of the function and look the gun.

Thanks for the input! I may plug the forward assist if it's less expensive. The dust cover is low bucks.

Any other handguards that folks can recommend?! The Troy does look like a winner!!!
 
Alright dudes...you ready for some picture-heavy-redneck-Alaska-man-cave-garage-tinker-toy TIME! :lol:

DISCLAIMER!!!!!: I went the total opposite of John.... no drill press... no sanding... no precision :shock: ... pretty much like that demo video, but without a dude vacuuming the shavings for me (They're on my floor, workbench... and maybe some in my hair...whats left of it)... only tools used were my Dremmel with a couple of cutting bits, a vice (most of the time) and my drill with the a few bits. From start to finish this was about 2 hours...

Here she is, untouched and ready for mishandling!

5-10 min in... I did use the 5/8th drill bit to remove some material for the dremmel to work around


Here you can clearly see the guide moldings. There's a big difference in the material hardness between the filler and the green polymer lower, you can certainly feel it as you're milling.


This is what happen when you get too close to the forward edge of the trigger well... you break through to magazine catch area... OOOPS... totally my fault, but i doubt it will affect any functioning.


Here we are close to the bottom... you can't see it real well, but I drilled all the way through to the trigger guard area, where the little molding tab was left over. This gave me a good visual reference on where to shave material at the bottom o the trigger well.


Pretty much complete... only thing left at this point was to open up the trigger hole a bit..




Now I was just getting sloppy and excited... here's my wonderful mess of a trigger hole :cool:


Last but not least was drilling the trigger pin holes and safety hole. I did measure the pin guides before I even began, and they seemed to be in spec with my Stag Arms lower as reference. I did not how ever drill the holes through... drilled each side separately using successively larger drill bits. All seems well at this point...


...and here was the moment of truth. I don't have the LPK yet for this, so I used my ALG trigger out my current AR.... some tweeking of the trigger hole... and a little shuffling through the rough spots... trigger and sear... good.... now for the hammer........in, and everything seemed to line up....



Drum roll.................... :? .................... :shock: ................. :eek:




Success... trigger worked, with reset and all! :D But I did encounter one glitch... seems like my safety holes weren't quite aligned... we're talking miniscule... so the right side hole is slightly lower than the left, causing the safety to sit low enough to interfere with consistent trigger function. It worked fine as long as I applied a little upward pressure on the safety (which hopefully the safety detent and spring will provide) If that doesn't solve it, I'll sand off a little from the back of the trigger to allow for a little more room. On safe, the trigger doesn't move one lick.

Now all that's left is to tap the handle screw hole and paint this sucker! I will consider the anti rotational pins, as I can see the polymer wearing over time and causing issues with fit and function. I don't think I'd bet my ass on this lower in a SHTF or self defense roll... but for $40 and 2 hours of my time, it will make a great range plinker and youngster trainer!

Oh...and of course I needed to enjoy a cold one for my "Hard" work tonight :D


(I might of had one before I started :oops: :twisted: )
 
Well done.

Glad everything worked out alright.

I'm ecstatic that all the holes lined up and you didn't have any issues.
 
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