Bare aluminum uppers and lowers

[caveman74]

I have seen several online vendors selling bare aluminum upper and lower receivers.

Would using them without having them anodized or cerokoted hurt anything?

I’d be using it for a range toy and not an important AR.

[HeruMew]

Even though I have forgotten it, Aluminum doesn't Oxidize the same way steel does.

Should be fine, but may look ugly unless it's "polished" aluminum. Just bare aluminum may have some tooling marks left in it.

YMMV.

[26 Inf]

Depending on how it is applied anodizing adds some abrasion resistance.

Aluminum will surface oxidize and become a dull greyish color.

They will work, I guess it just depends on what you want.

I have heard that the dimensions of the lower and upper are adjusted to take the thickness of the anodization into account, but I don't know if that is true.

Here is what I found:

There are two types of anodizing, Chromic Anodize (MIL-A-8625E, Type 1 & 1B, Class 1 & 2) and Hard Anodize (MIL-A-8625E, Type III, Class 1 & 2). Chromic anodize is not the same as the Hard Coat anodize. The key as to what finish that is applied to aluminum AR15/M16 type receivers is the TYPE (I, IB, or III). A manufacturer may state that it meets MIL-A-8625E, but if no type is specified you don't know what you're getting. It must be type III for Hard Anodize to meet the spec for the M16. Types I & IB, class 2 can be dyed to the black or dark grey; the dye can rub off.

Type III, class 2 can be dyed and is specified on the contract drawings. Hard anodizing color will vary from light tan to black depending on alloy (this should be 7075 T-6 for AR15/M16 uppers and lowers) and can be dyed in darker colors depending on the thickness of the anodizing. Hard anodize coating penetrates the base metal as much as it builds up on the surface. This provides a VERY hard coating. If a thickness is unspecified on the contract drawings then the thickness shall be nominally 0.002" thick. The term THICKNESS includes both the buildup and the penetration. https://www.fulton-armory.com/faqs/AR-FAQs/Mil_Spec.htm

All anodizing is a conversion coating in that a portion of the base materials surface is converted from raw aluminum into aluminum oxide. In general terms, for Type III anodize ½ of the coating thickness penetrates into the surface of the parts while the other 1/2 builds up on the surface. Thus for a typical 0.002” thickness requirement, there is 0.001” dimensional change per surface. https://www.anoplate.com/finishes/hardcoat-anodize/

Based on that I don't think you will have problems with pins flying out of over-sized holes on an unfinished receiver.

If it is a range toy I'd try my hand at applying a coating of some sort. It's kind of fun to do and increases your 'handiness.' Norrell's Moly Resin is one I've used - https://molyresin.com/

There is a wide selection on do-it-yourself coatings to choose from. I'd have at it.

[GH41]

I have seen several online vendors selling bare aluminum upper and lower receivers.

Would using them without having them anodized or cerokoted hurt anything?

I’d be using it for a range toy and not an important AR.

Link us to these people that sell them bare. The only ones I have seen bare are the 80% lowers.

[adh]

can these unfinished lowers be any cheaper than $40 delivered PSA lowers.....ETA it appears the $40 delivered promo is now gone so now $49 with shipping
https://palmettostatearmory.com/psa-ar-15-lower-safe-fire-1728.html
the PSA lowers are totally good to go for building an AR IMO as long as you use quality parts to complete them

wait long enough and I'm sure the free freight will come back

[Artiz]

If you're building an AR just to look at and shoot every now and then, okay fine. If you're anywhere near the area of "I'm gonna use it" then forget it, it's a bad idea alltogether. If you're anywhere near the ocean forget it. Hardcoat anodizing is an engineered coating, it protects the base aluminium alloy from friction/wear and corrosion because yes, aluminium does corrode. If you're introducing an electrolyte (seawater/salty humid air, sweat, etc) bare aluminium will undergo galvanic corrosion with the steel components and will basically dissolve away. There has been NAVY guns who's barrels basically fell off because saltwater got inbetween the barrel nuts and receivers, the receiver threads weren't 100% protected with anodizing and the upper threads dissolved away with time. Anodizing is aluminium oxide, so it's HARD, however it isn't magic, it's resistance to wear verus it's hardness is dependent on the base aluminium alloy, no aluminium alloy is hard enough to prevent gouging from impacts. However 7075-T6 may be a hard alloy, but a bare 7075-T6 receiver set is going to wear at an accelerated rate compared to an anodized one. Let alone the fact that it's completely unprotected from galvanic corrosion.


Link us to these people that sell them bare. The only ones I have seen bare are the 80% lowers.

Shittiy Canadian manufacturers "cough" NEA/BCL "cough" who don't know what they're doing have been releasing bare receiver sets for sale.

[Stickman]

I have seen several online vendors selling bare aluminum upper and lower receivers.

Would using them without having them anodized or cerokoted hurt anything?




Yes, anodizing is an important part of the overall process, and it isn't about making it black colored. Anodizing hardens the surface of what is otherwise a fairly soft material. Speaking as someone who owns some ARs which are cerakoted and not anodized, the difference is obvious even living in the safe where they only get knocked into other weapons.

Cerakote does nothing realistically to make a function difference as the unanodized material can't take abuse.

I wouldn't want a knife that wasn't hardened/ heat treated. I wouldn't want a receiver that wasn't hardened/ anodized.

[caveman74]

Link us to these people that sell them bare. The only ones I have seen bare are the 80% lowers.

When I get home later this evening I’ll post links.

I don’t remember who was selling them, but I found them by searching for stripped bare aluminum AR15 lowers.

[caveman74]

Yes, anodizing is an important part of the overall process, and it isn't about making it black colored. Anodizing hardens the surface of what is otherwise a fairly soft material. Speaking as someone who owns some ARs which are cerakoted and not anodized, the difference is obvious even living in the safe where they only get knocked into other weapons.

Cerakote does nothing realistically to make a function difference as the unanodized material can't take abuse.

I wouldn't want a knife that wasn't hardened/ heat treated. I wouldn't want a receiver that wasn't hardened/ anodized.

If I were to buy a bare upper, how much would I be looking at to get it anodized?

I thought it would save few bucks with a bare aluminum upper because it would be mated to an Anderson lower and a Bear Creek barrel, nothing spectacular.


If it would cost more than buying a regular stripped upper than it isn’t worth it.

[Artiz]

If I were to buy a bare upper, how much would I be looking at to get it anodized?

I thought it would save few bucks with a bare aluminum upper because it would be mated to an Anderson lower and a Bear Creek barrel, nothing spectacular.


If it would cost more than buying a regular stripped upper than it isn’t worth it.

You need to find a good anodizer that does actual receivers, first. It's pretty much the same price to anodize one receiver or a full batch of receivers. They charge the batch of anodizing. And it's very expensive, around here just shy of a thousand bucks.

[Metric Matt]

Link us to these people that sell them bare. The only ones I have seen bare are the 80% lowers.

https://aeroprecisionusa.com/ar15-stripped-upper-receiver-uncoated.html

[GH41]

So the bare one is 14 bucks cheaper than the black anodized one. It makes sense if you are going to cerakote it. If not it makes little sense.

[caveman74]

So I ended up getting a regular anodized upper.

Its a blem stripped upper from Advanced Armament, $52 with shipping.

If there is such a thing as clear anodizing,I think that a upper/lower set would look cool.


Thanks all

[HeruMew]

So I ended up getting a regular anodized upper.

Its a blem stripped upper from Advanced Armament, $52 with shipping.

If there is such a thing as clear anodizing,I think that a upper/lower set would look cool.


Thanks all

Yes, and no.

Anodizing can be done in a plethora of colors; more so, unless my information is inaccurate, can be adjusted for depth, hardness, and a few other factors.

If you look for "Anodized (enter aluminum/metal product here)" in google, you will find plenty of places to purchase said product with, usually, a variety of color options.

So, no, it wouldn't really be "clear" (unless there is a hardening process without dyes) but you could get a very smooth and shiny silver look to it for sure.

Here's a good example of dyes and process:

https://www.youtube.com/watch?v=QBWpB80xxZI

YMMV when it comes to hardening in the case of ARs, o-course. This is purely based off of what is easily accessible information about the anodizing process. I could be far off when it comes down to ARs and that process entirely.

[jackblack73]

The Honey Badger is supposedly clear anodized, which accounts for its color.

[wanderson]

I've always liked the look of bare of 90% missing finishes on receivers. When my LGS got some unfinished Mag Tactical magnesium lowers for cheap ($25) I snagged one.

So far it's about two years old and looks new. I only polished it once with some old polishing cloth I had for magnesium wheels. Some of you are probably too young to remember when aftermarket wheels were available in bare magnesium. it's on an upper shooting corrosive ammo (7N6) so it gets a regular bath in hot soapy water.

Full disclosure, magnesium isn't as strong as aluminum. There are some pics of broken magnesium receivers out there. And the weight difference is negligible. But for a range toy, it works. So if this is the look you're going for, it's a cheap option that doesn't appear to need much maintenance.

[HelloLarry]

The FCG holes will eventually egg out on a bare/ceracoat-only receiver.

[556BlackRifle]

Personally I'd STF away from that. Just not worth the hassle IMO.

[MistWolf]

You can do clear anodizing, but it won't be Type III. Type III comes out dull grey or a dull golden color depending on the alloy.

[Chris Bonesteel]

Even if youre going to cerakote, youd still want the anodizing underneath. The only reason to buy a non anodized reciever is if you plan on making modifications to it, then having it anodized, saving you the stripping step

[GH41]

I've always liked the look of bare of 90% missing finishes on receivers. When my LGS got some unfinished Mag Tactical magnesium lowers for cheap ($25) I snagged one.

So far it's about two years old and looks new. I only polished it once with some old polishing cloth I had for magnesium wheels. Some of you are probably too young to remember when aftermarket wheels were available in bare magnesium. it's on an upper shooting corrosive ammo (7N6) so it gets a regular bath in hot soapy water.

Full disclosure, magnesium isn't as strong as aluminum. There are some pics of broken magnesium receivers out there. And the weight difference is negligible. But for a range toy, it works. So if this is the look you're going for, it's a cheap option that doesn't appear to need much maintenance.

Saying that magnesium isn't as strong as aluminum isn't fair. Saying the poorly poured Mag Tactical lower is not near as strong as an aluminum forged mil spec lower would be fair.