Making Skinflint look Gucci

[pastera]

80% budget build
Lowest bidder on all parts
The only place I 'splurged' is for a 20" stainless heavy barrel upper
Rattle can paint
20 minutes with the whet stones to clean up the garbage trigger
Pulled the stock apart to remove the adjuster machined a new locking pin and made a plastic plug (need to drill out the plug to get to the locking pin and then still need tools to get to the locking pin below the surface)

Running total so far $362.43
Need to put a compliant muzzle device on once I have the upper in hand.
Might just machine a stainless thread protector to pin and TIG.

 

[akma]

If you're interested Rust oleum High heat flat black 248903 is a spot on match for AR's

Robot or human?

 

[pastera]

If you're interested Rust oleum High heat flat black 248903 is a spot on match for AR's

Robot or human?

I have some but not in a rattle can
Hit it with Rust Oleum flat primer and gloss top coat with a bake cycle between coats and after
Even with baking the adhesion isn't great so I'll likely strip it sometime this summer, scuff it with scotch Brite and then use an etching primer

 

[akma]

Maybe a light blasting to give some tooth for the paint to adhere?
I seriously have had zero with adhesion or wear issues doing this on parts.

 

[pastera]

Maybe a light blasting to give some tooth for the paint to adhere?
I seriously have had zero with adhesion or wear issues doing this on parts.

You're probably 100% correct.
Did a spray down with brake cleaner to remove oils but was too lazy to search out a scotchbrite pad to scuff it up well.

It's not hard to disassemble and strip so I might do a better job this summer.
Or get some PH- from the pool store and try anodizing

 

[paul73]

try anodizing

it would be better, i think, but, from other perspective - if i would be doing it - i would do same you did - means a spraypaint only. as horses for courses. and no ragrets.

 

[pastera]

NcStar 4-16 that was sitting on the shelf (inherited)
So even if I purchased it the build would be around $500

 

[paul73]

View attachment 727904
NcStar 4-16 that was sitting on the shelf (inherited)
So even if I purchased it the build would be around $500

i would spray black the barrel and gas block too. but i dig black guns, that do not reflect much.

 

[pastera]

i would spray black the barrel and gas block too. but i dig black guns, that do not reflect much.

It's a work in progress toy.
Need to boresight it and see if it groups at all.
If it does, I'll look at good glass and a drop in trigger.
If not, I'll throw some iron sights on it and be happy with a $400 gun.

But if it does group anywhere near decent, I get to laugh at people pushing $300 stripped lowers as a necessity for precision.

 

[paul73]

It's a work in progress toy.
Need to boresight it and see if it groups at all.
If it does, I'll look at good glass and a drop in trigger.
If not, I'll throw some iron sights on it and be happy with a $400 gun.

But if it does group anywhere near decent, I get to laugh at people pushing $300 stripped lowers as a necessity for precision.

if you lapped the upper and barrel sits tight - why would it not group properly? it is not much in there that may affect the way it shoots. it will shoot.

$300 stripped lowers - not sure, i think reptile was selling for $1500. aero M4 goes for what, around $80 or so plus the xfer fee of $50 - so anything under $150 is ok-ish.
a properly made 80% should work just fine, if geometry isn`t f#cked up. i would be more careful about trigger, try it with only 2-3 in a mag first time, or i would just use a drop-in trigger assembly like triggertech in there, to remove holes alignment from the equation completely.
it may contradict with a cheap pos concept, of course.

 

[paul73]

It's a work in progress toy.
Need to boresight it and see if it groups at all.
If it does, I'll look at good glass and a drop in trigger.
If not, I'll throw some iron sights on it and be happy with a $400 gun.

But if it does group anywhere near decent, I get to laugh at people pushing $300 stripped lowers as a necessity for precision.

and btw if you decide to make an 80% ar10 - i have a 7.62 barrel, wilson arms 16" 1/10 that i can give you for real cheap, as i have no use for it. it is also fluted so weights only 2lbs, but, i switched to faxons.

 

[pastera]

The complete upper was $250 shipped
While I expect okay performance, I'd be very happily surprised for moa or under for that price.

Lower is to spec - was done on a cnc.

Drop in trigger is definitely in the future if it hits MOA or better - I polished the garage trigger I have for it but the reset sucks and the pull is 5+ lbs. Rather invest $100 in a drop in than new springs and a ton of work to get a mil spec down to 3.5 lbs

 

[paul73]

The complete upper was $250 shipped

you mean it came WITH the barrel attached? i would take it apart, lapped and re-torqued. i had to do it to an every single upper i bought, 10 or 15, in order to make them shoot well.
most were undertorqued. i torque them high, in 75-80 area, i think it works the best that way. with the lube on threads, of course.

that is also a thing - not a single pre-made upper was lubed, and, well, it will be a problem in time if you ever decide to uncouple it.

 

[SKumar]

$362?? Pfft. Anderson had a complete AR for like $349 last black friday. Skinflint more! (kidding. Great job. I love cheap ARs!)

 

[pastera]

you mean it came WITH the barrel attached? i would take it apart, lapped and re-torqued. i had to do it to an every single upper i bought, 10 or 15, in order to make them shoot well.
most were undertorqued.

If it doesn't perform, I'll hit you up for some tips on tuning it up.
I broke my initial intent of seeing what the cheapest build out of the box would do by polishing the trigger - just couldn't leave it alone after dry firing the lower and feeling the boulders.

 

[drgrant]

If that's the first 80 youve done even I cant call that total flinting.... that's "economical prototyping". Like you planned going in knowing that if you f***ed up that lower you left the option where you could just sideline the whole thing and not feel bad about it..

Hardcore flinting is like buying a poverty pony fir 50 bucks clean and waiting 4 years to get throwaway parts. I have almost enough junk bin near throwaway parts to build a flint AR.

 

[pastera]

$362?? Pfft. Anderson had a complete AR for like $349 last black friday. Skinflint more! (kidding. Great job. I love cheap ARs!)

The $362 includes shipping and taxes
So $349 with taxes would be $370

So when you're riding the poverty pony $8 makes a difference

 

[pastera]

If that's the first 80 youve done even I cant call that total flinting.... that's "economical prototyping". Like you planned going in knowing that if you f***ed up that lower you left the option where you could just sideline the whole thing and not feel bad about it..

Hardcore flinting is like buying a poverty pony fir 50 bucks clean and waiting 4 years to get throwaway parts. I have almost enough junk bin near throwaway parts to build a flint AR.

Not the first but the first on my desktop CNC. Last one was turning handles and counting turns (that's painful)
Have one left to machine but my son wants to do that one.

Next one for me will be an AR-10.
Problem is the safe is getting full.

 

[paul73]

Next one for me will be an AR-10.

man, you gotta graduate into 0% builds, 80% is for newbies!
CNC rules.

 

[pastera]

man, you gotta graduate into 0% builds, 80% is for newbies!
CNC rules.

My mill doesn't have the Z to do the buffer tube.
However I haven't tried to jig up my 7x12 mini lathe to do that operation - would be slow and I'd need to add weights to balance it but I think I could do it.

 

[pastera]

So first issue and first annoyance.

Annoyance:
Pulled the muzzle device in preparation to cut a nice smooth/polished thread protector for a somewhat seamless look. Threads were very tight coming off because they didn't clean up a damn thing. A quick wire brushing of the threads and the device spun on clean.
Muzzle face is a nice, clean 11° cut with no chatter marks and threads are decent once cleaned
Muzzle device is machined okay but has essentially zero finish work to clean and deburr (it's going in the trash anyway. p
Barrel machining: A
Detail work: D

Issue:
I have two "trash can" 4x16 scopes with rings.
Mounted the BSA without thinking and found the rings to be way too short (1" height)
This morning pulled the BSA and mounted a NcStar with 1.6" height rings but couldn't get it to lock tight on the rail.
Quick OD check on the rail shows .828" on a spec of .835"-0.005".
Haven't checked the datum since I need to machine gages for that so I don't know if the rings are out also (likely) or the upper is bad.
Not hard to fix with a shim on the clamp and at $250 for a complete upper, it's not unexpected.

 

[paul73]

Quick OD check on the rail shows .828" on a spec of .835"-0.005".

yeah, shims to the rescue. it is not unexpected. or, in some cases, you can trim prongs on the rings to make sure it will close tighter. or whatever design the rings got.

AR rings are typically 1.5" minimum, with lower rings you will not be able to see scope well anyway.

 

[pastera]

yeah, shims to the rescue. it is not unexpected. or, in some cases, you can trim prongs on the rings to make sure it will close tighter. or whatever design the rings got.

I'll throw a couple of layers of aluminum tape to each contact surface on the ring clamps to see how far its out.
If it locks up well with one layer then I'll just cut 0.002" the ring surface that's bottoming out. I don't think a 0.001" offset over the barrel centerline is going to be an issue.

 

[Mtn_Guy]

Waiting to see this in the WTS section listed at $2000 with Goose Rulz…

 

[pastera]

One layer of tape has the rings locking up properly on the rail so it's tolerance stackup since another set of rings does lock up on the upper's rail.
Cheap + cheap = out of spec by 0.002-3"

 

[pastera]

Waiting to see this in the WTS section listed at $2000 with Goose Rulz…

$1500 cash for you, today only!

 

[paul73]

I'll throw a couple of layers of aluminum tape to each contact surface on the ring clamps to see how far its out.
If it locks up well with one layer then I'll just cut 0.002" the ring surface that's bottoming out. I don't think a 0.001" offset over the barrel centerline is going to be an issue.

i would take a piece of .223 or .308 brass, cut it, get those halves and use them instead. tape will compress and let go.
but if tape worked - just saw it - a done deal then. whatever works.

 

[akma]

I would recommend anti rotation pins to keep the pins from egging out (the hammer pin has a ton of pressure on it) and in proper spec.

4PACK High Precision.154 Non-Rotation Anti-Walk Hammer Trigger Small Pin Hole | eBay

Find many great new & used options and get the best deals for 4PACK High Precision.154 Non-Rotation Anti-Walk Hammer Trigger Small Pin Hole at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

[pastera]

i would take a piece of .223 or .308 brass, cut it, get those halves and use them instead. tape will compress and let go.
but if tape worked - just saw it - a done deal then. whatever works.

Tape is adhesive backed aluminum, not going anywhere.

 

[pastera]

I would recommend anti rotation pins to keep the pins from egging out (the hammer pin has a ton of pressure on it) and in proper spec.

4PACK High Precision.154 Non-Rotation Anti-Walk Hammer Trigger Small Pin Hole | eBay

Find many great new & used options and get the best deals for 4PACK High Precision.154 Non-Rotation Anti-Walk Hammer Trigger Small Pin Hole at the best online prices at eBay! Free shipping for many products!

www.ebay.com

If the holes egg out I'll punch them out and press in steel bushings, or just machine another $40 80% lower.

But I am also looking at a JMT trigger if the upper seems like it will perform better than MOA.