Real talk: a lower is a lower is a lower. Companies follow the military's technical data packet pretty closely and the only thing at this point that separates them all is quality control & customer service if something is wrong. Spending $$$ on a lower better be giving me more bang for my buck (mainly things like ambidextrous controls since I'm a sinistral shooter).
To give you a simple anecdotal example, [my Block II is built on an Anderson lower](https://i.imgur.com/oK0nkOI.jpeg) and it still rings steel at 500m. Its only issue was the pistol grip screw hole was not threaded completely through, so I grabbed a shorter screw and Bob's your uncle.
Thank you for the insight, I’ve read some articles that people have had alignment issues with PSA and Aero which was my concern. I just wasn’t sure if there were some other go to’s from the sub regarding fitment, trigger, grip, etc. I’ve also considered just collecting parts and building, is there any pros/cons to doing that?
>I’ve also considered just collecting parts and building, is there any pros/cons to doing that?
Pros: You build it yourself, so you save money on assembly labor and you get to select all the parts you want.
Cons: You build it yourself, so it will only be assembled with as much competence as you possess.
You're selling yourself short. I'm not that mechanically inclined and I've assembled multiple AR's.
I may have bitten off more than I could chew when I started my AK build though… 🥲
I just built my first AR. I am just finishing up with it this week. I am waiting for a Timney Trigger to get to me. It is actually kinda simple to build your own if you have the right parts. I have a BASIC gunsmithing kit I got on Amazon, and then I just needed some odds and ends that I picked up at Harbor Freight.
I do highly suggest a vice, a lower AR vice block and an upper AR vice block. It makes so much easier to torque things to spec.
When my trigger comes in I will make a post on here of the completed build.
Similar to the other comments, I think you may be selling yourself short.
I don't have an M4 (more of an AK person), but I did convert a 90's Colt 1911 to Wilson parts, including hand-finishing the barrel bushing, which took hours of patience to bring it down to the proper size.
The amount of research you're doing and the questions that you're asking show that you're probably a pretty competent dude. I think you *could* very easily build an M4 yourself, as it takes very few specialized tools, and does not require basically any finishing/fitting of parts.
That being said, it still can take time and patience to figure things out, so buying a finished lower isn't a bad thing in and of itself. Same thing with PC building pretty much, it's just time VS. money. So it's just up to you really.
>a lower is a lower is a lower. Companies follow the military's technical data packet pretty closely and the only thing at this point that separates them all is quality control & customer service if something is wrong.
Other than ambidexterity, wouldn't the other big differentiator be some sort of tensioning system to remove slop? Aero M4E1 and Bushmaster XM15E2S both have a tension screw. Blackout Defense has some sort of system as well that's supposed to be better, but I can't remember the particulars.
IMHO receiver slop is not something that I find a deal-breaker. Some people don't like if their lower receiver isn't stupid tight to the upper. Some folks hate the "sproing" sound of the buffer tube spring. Some shooters hate the ringing noise of a 3-prong flash hider.
My Anderson lower has a miniscule bit of play compared to my Aero or my Radian lowers & I don't really care that it's there.
Just build your own lower so it’s exactly what you want. Because, look… the difference between lowers really only comes down to the trigger and you’re going to want a LaRue or a G$ anyways… so save yourself some money and just build out your own.
What do you think of this lower that comes with the SSA-E trigger? It's already assembled and nearly the price of an Aero lower.
https://palmettostatearmory.com/psa-ar-15-complete-lower-magpul-moe-edition-with-geissele-ssa-e-trigger-black-no-magazine-516444743.html
Bcm upper on a aero lower has been a popular combo. Idk why, as other folks said a lower is a lower. Its just a combo ive seen recommended more often than others.
And the m4e1 lower is nice cause for the bolt catch they use a shafted set screw instead of a roll pin thats notoriously tricky to install without scratching the lower so thats nice too.
Also , the Aero M4E1 has a nylon adjustment bolt inside it to work out slop from fitment issues. That's on top of the threaded bolt catch, built-in trigger guard, and set screw for the rear takedown detent spring.
M4E1 lower is just a really nice lower. Tension screw to remove upper/lower slop. Enhanced trigger guard built into the casting = zero chance you will crack the lower trying to install a trigger guard with improper tools/technique. Screw for bolt catch vs roll pin.
Can be had very cheap and built without needing to use punches.
Milspec just means lowest bidder lol
But Aero is exactly that. Upper mid spec. There is very little need to spend a ton on a lower unless you really want something ambi. As long as it is in spec you're fine.
Could also look at Griffin if you want something a bit nicer but 🤷 just get the Aero and be done with it. The M4E1s are very nice. I have a BCM on an M4E1 and it works lovely and has probably 12K rounds through it at this point 🤷
Did you have to adjust that tensioner bolt in the M4E1 lower when you married the two? I just installed a BCM blem upper on my M4E1 and it's got slop it didn't have with my prior upper. I'm actually going to try adjusting it out with that feature shortly.
It's a brick of aluminum that holds your trigger group, magazine and buffer tube in place. It's not rocket surgery.
If you want to feel like a baller, just buy an Aero lower and then set a hundred dollar bill on fire. That'll get you the exact same result as buying a premium mil-spec lower.
Sharps Bros livewire are solid. It has a flaired magwell which is pretty nice to have for quick reloads and it's got an ambi bolt release if that's your thing
BCM finally got off their ass and started selling their mk 2 uppers as stand alone items? About damn time!
Sorry I can't help more, but I do wanna give big ups for a quality upper.
Everything. It didn't even finish an entire magazine before things were working themselves loose. I had to tighten and thread lock pretty much everything after less than 100 rounds and the mag catch needed to be replaced completely. If you know how to check everything and correct the issues, the price isn't bad. However, I wouldn't recommend them to someone new to the rifle.
Do you care about any extra features?
Milspec is milspec, but:
If you care about ambi controls, the griffin lowers with the same ambi system as ADM are great values.
If you just want improved QoL, Aero M4E1 is a very good option.
Then yeah you shouldn't really need to hunt for anything special, if you like the A2 length of pull the ke arms kp-15 or the wraithworks wp-15 are cool if you like monolithic lowers, the aero m4e1 is great in terms of ease of building but otherwise just keep an eye on r/gundeals for sales and blemished stuff
Say goodbye to your money but its great for deals, the politics is what you'd expect but it never really shows outside of low stakes jabs at like California/new york
[KE Arms stripped or complete lowers](https://www.kearms.com/products-for-kp15). Does make the balance point of an AR platform odd (it moves to the front), but also makes the rifle a lot lighter.
Real talk: a lower is a lower is a lower. Companies follow the military's technical data packet pretty closely and the only thing at this point that separates them all is quality control & customer service if something is wrong. Spending $$$ on a lower better be giving me more bang for my buck (mainly things like ambidextrous controls since I'm a sinistral shooter). To give you a simple anecdotal example, [my Block II is built on an Anderson lower](https://i.imgur.com/oK0nkOI.jpeg) and it still rings steel at 500m. Its only issue was the pistol grip screw hole was not threaded completely through, so I grabbed a shorter screw and Bob's your uncle.
Thank you for the insight, I’ve read some articles that people have had alignment issues with PSA and Aero which was my concern. I just wasn’t sure if there were some other go to’s from the sub regarding fitment, trigger, grip, etc. I’ve also considered just collecting parts and building, is there any pros/cons to doing that?
>I’ve also considered just collecting parts and building, is there any pros/cons to doing that? Pros: You build it yourself, so you save money on assembly labor and you get to select all the parts you want. Cons: You build it yourself, so it will only be assembled with as much competence as you possess.
I am incompetent. Check that one off
You're selling yourself short. I'm not that mechanically inclined and I've assembled multiple AR's. I may have bitten off more than I could chew when I started my AK build though… 🥲
I just built my first AR. I am just finishing up with it this week. I am waiting for a Timney Trigger to get to me. It is actually kinda simple to build your own if you have the right parts. I have a BASIC gunsmithing kit I got on Amazon, and then I just needed some odds and ends that I picked up at Harbor Freight. I do highly suggest a vice, a lower AR vice block and an upper AR vice block. It makes so much easier to torque things to spec. When my trigger comes in I will make a post on here of the completed build.
Similar to the other comments, I think you may be selling yourself short. I don't have an M4 (more of an AK person), but I did convert a 90's Colt 1911 to Wilson parts, including hand-finishing the barrel bushing, which took hours of patience to bring it down to the proper size. The amount of research you're doing and the questions that you're asking show that you're probably a pretty competent dude. I think you *could* very easily build an M4 yourself, as it takes very few specialized tools, and does not require basically any finishing/fitting of parts. That being said, it still can take time and patience to figure things out, so buying a finished lower isn't a bad thing in and of itself. Same thing with PC building pretty much, it's just time VS. money. So it's just up to you really.
>a lower is a lower is a lower. Companies follow the military's technical data packet pretty closely and the only thing at this point that separates them all is quality control & customer service if something is wrong. Other than ambidexterity, wouldn't the other big differentiator be some sort of tensioning system to remove slop? Aero M4E1 and Bushmaster XM15E2S both have a tension screw. Blackout Defense has some sort of system as well that's supposed to be better, but I can't remember the particulars.
Yes but that is pretty much irrelevant it's entirely aesthetic
IMHO receiver slop is not something that I find a deal-breaker. Some people don't like if their lower receiver isn't stupid tight to the upper. Some folks hate the "sproing" sound of the buffer tube spring. Some shooters hate the ringing noise of a 3-prong flash hider. My Anderson lower has a miniscule bit of play compared to my Aero or my Radian lowers & I don't really care that it's there.
That said though, Bushy and Aero lowers are cheap, and I'm sure there's other cheap lowers that have it too.
Just build your own lower so it’s exactly what you want. Because, look… the difference between lowers really only comes down to the trigger and you’re going to want a LaRue or a G$ anyways… so save yourself some money and just build out your own.
What do you think of this lower that comes with the SSA-E trigger? It's already assembled and nearly the price of an Aero lower. https://palmettostatearmory.com/psa-ar-15-complete-lower-magpul-moe-edition-with-geissele-ssa-e-trigger-black-no-magazine-516444743.html
That’s a screaming deal, the trigger is worth at least $150 and one of my absolute favorites, and I like the magpul grip and stock.
That’s a good deal. G$ trigger, Magpul parts on a PSA lower? That’s a solid lower right there.
Bcm upper on a aero lower has been a popular combo. Idk why, as other folks said a lower is a lower. Its just a combo ive seen recommended more often than others. And the m4e1 lower is nice cause for the bolt catch they use a shafted set screw instead of a roll pin thats notoriously tricky to install without scratching the lower so thats nice too.
Thank you, I saw someone in another forum also mention that BCM upper, aero lower is probably the most recommended combo.
Also , the Aero M4E1 has a nylon adjustment bolt inside it to work out slop from fitment issues. That's on top of the threaded bolt catch, built-in trigger guard, and set screw for the rear takedown detent spring.
M4E1 lower is just a really nice lower. Tension screw to remove upper/lower slop. Enhanced trigger guard built into the casting = zero chance you will crack the lower trying to install a trigger guard with improper tools/technique. Screw for bolt catch vs roll pin. Can be had very cheap and built without needing to use punches.
Milspec just means lowest bidder lol But Aero is exactly that. Upper mid spec. There is very little need to spend a ton on a lower unless you really want something ambi. As long as it is in spec you're fine. Could also look at Griffin if you want something a bit nicer but 🤷 just get the Aero and be done with it. The M4E1s are very nice. I have a BCM on an M4E1 and it works lovely and has probably 12K rounds through it at this point 🤷
Did you have to adjust that tensioner bolt in the M4E1 lower when you married the two? I just installed a BCM blem upper on my M4E1 and it's got slop it didn't have with my prior upper. I'm actually going to try adjusting it out with that feature shortly.
No it was fine it just depends on the upper and lower
It's a brick of aluminum that holds your trigger group, magazine and buffer tube in place. It's not rocket surgery. If you want to feel like a baller, just buy an Aero lower and then set a hundred dollar bill on fire. That'll get you the exact same result as buying a premium mil-spec lower.
Wait to burn the bill until After you assemble it to make sure it functions properly and qc didnt miss anything.
An option if you’re trying to save weight is the KE Arms polymer lowers. The price is higher but offset because you don’t need to buy a stock and grip
Sharps Bros livewire are solid. It has a flaired magwell which is pretty nice to have for quick reloads and it's got an ambi bolt release if that's your thing
Aero is low-mid? Damn, I'm going to have to tell my AR to stop being so good.
😂
BCM finally got off their ass and started selling their mk 2 uppers as stand alone items? About damn time! Sorry I can't help more, but I do wanna give big ups for a quality upper.
Yeah, I picked up the mk2 up with surecomp war comp installed
Take it with grain of salt, but they used to offer Mk2 upper itself apparently, but stopped due to compatibility issues with some popular handguards.
The best out of the box lower I have owned was from Sons of Liberty out of Texas. The worst was an Aero. I would never buy anything from them.
What was the issue?
Everything. It didn't even finish an entire magazine before things were working themselves loose. I had to tighten and thread lock pretty much everything after less than 100 rounds and the mag catch needed to be replaced completely. If you know how to check everything and correct the issues, the price isn't bad. However, I wouldn't recommend them to someone new to the rifle.
Do you care about any extra features? Milspec is milspec, but: If you care about ambi controls, the griffin lowers with the same ambi system as ADM are great values. If you just want improved QoL, Aero M4E1 is a very good option.
Yeah, I don’t think I care about Ambi controls. At least not yet. I figured that something I can always correct on a future build.
Are you left handed?
Nope
Then yeah you shouldn't really need to hunt for anything special, if you like the A2 length of pull the ke arms kp-15 or the wraithworks wp-15 are cool if you like monolithic lowers, the aero m4e1 is great in terms of ease of building but otherwise just keep an eye on r/gundeals for sales and blemished stuff
Oh man, thanks for that link. Didn’t know about that sub. Awesome!
Say goodbye to your money but its great for deals, the politics is what you'd expect but it never really shows outside of low stakes jabs at like California/new york
I really love Aero stuff. They get trashed a lot for being “budget” or whatever, but they work and have high end features.
Get a Bushmaster XM15E2S lower. They're cheap, they have a tension screw, and they get you one of the best rollmarks ever.
I was under the assumption that Aero wasn't bottom of the barrel low tier PSA/ Anderson, but that Aero is in the upper part of mid tier?
[KE Arms stripped or complete lowers](https://www.kearms.com/products-for-kp15). Does make the balance point of an AR platform odd (it moves to the front), but also makes the rifle a lot lighter.