Quick review of Aero Precision M5 lower build kit

[fnfalguy]

Ive been sitting on a M5 lower I picked up a while ago from a now Thai ex-pat birdy. I was waiting for Black Friday and cyber Monday sales to finish it off. The lower parts kit arrived today. First impressions weren’t all that impressive to me. All the parts, with the exception of the stock parts were in one bag. I didn’t use their stock as I recently got a pinned one from somebody in a free state. For those who haven’t built hundreds of lowers ( @Eddie Gunks ) it took some time to organize the springs and what not. Two big differences from my typical building experience had to do with two screws. One I loved and the other I wanted to heat up to it’s melting point to hear it scream tiny threaded cries. In the attached photo there are two parts circles. One is the typical pin used for the bolt catch. That wasn’t included. In its place was a threaded pin which made that installation a breeze with no risk of marring the receiver, which was threaded to take the pin. The evil set screw is for keeping the rear take down detent in place and that took way to long to install. It’s so simple, all you have to do is insert the detent pin, then the spring, convince the spring it really wants to compress in a straight direction and then marry up the threads of the set screw with the receiver. In reality, you also have to listen for where the spring launched to, get on your knees to find it and then yell at the dog for snickering at you.

After about 15 or so agonizing minutes I gave up, found a tin snip and just cut the damn spring about 4-5 coils shorter. I did call customer service before I attacked the buildso they could initially explain what that short set screw was for. Apparently it’s two purposes in life are retaining the take down pin and torturing the end user. While on the phone with them, I noticed the bag o parts was missing a detent pin as well, so that’s on its way. Long story short, the trigger feels good, I hate their packaging, their customer service was great and I felt like a simian trying to fornicate with a football during part of this build. Oh yeah, and I fucking hate what NY has made me do to the AR system.

 

[meketrefe]

Thanks for the review! ..what is that thing where the grip goes?

 

[fnfalguy]

@meketrefe That good Sir is an attachment which does not protrude conspicuously beneath the receiver. Spur grip. I don’t want to go with a fixed magazine, so it’s a pinned stock, spur grip and will have a nekkid muzzle. I’ll add a new thread when it’s assembled. I’m also using Aero’s scope mount, and I found in the closet a spare Leupold VXII 3-9 so I’ll be mounting that as well.

 

[meketrefe]

@meketrefe That good Sir is an attachment which does not protrude conspicuously beneath the receiver. Spur grip. I don’t want to go with a fixed magazine, so it’s a pinned stock, spur grip and will have a nekkid muzzle. I’ll add a new thread when it’s assembled. I’m also using Aero’s scope mount, and I found in the closet a spare Leupold VXII 3-9 so I’ll be mounting that as well.

Oh, I see. Didn't realize they sold this still. I remember now. Agree do not pin a magazine to a perfectly functional autoloader. That would make no sense. But be careful with those as you can loose control of the firearm. Instead check one of those Galactic Euro Trans stocks like the FRS that actually works quite well. Or make a strap with wide stiff nylon. ...anything but loosing control of a firearm. ... or neutering one.

 

[BDinPutnam]

I have to admit it has been a while since I looked at parts or did a build. That rear take down pin, mil-spec stock, was a problem enough for them to do a set screw? I've built several but certainly not enough to even say I stayed at a Holiday Inn last night, but I've never had much trouble with that bit.

Appreciate the detailed write up, looking forward to hearing how the trigger is in operation.

 

[Saltwater60]

I bought a smith and Wesson mp lpk and loved it. It came in a great package with the name of every little price separated and labeled. I think thentrigher for a $54.00 kit is nice. I’ll probably clean it up a bit and see if I can’t make it a bit smoother. No problems with the install except fitting the pistol grip to the receiver was a bit tight and took a little love to make it go on.

 

[Podmonkey]

In my local Gander Outdoors they have the Aero upper and lower also. Plus all the parts kits, barrels, hand guards, BCG and related parts as well as all the furniture. I keep thinking it might be interesting to to a full Gander build and see how it turns out.

 

[fnfalguy]

So, got the rest of the parts needed in today. As one would expect, the fit and finish were very good and the colors match well. Since its the same manufacturer, I would have been surprised if it didn’t. Now its time to find time to get to the range before we get covered up with snow.

 

[Blimey]

Looks good.

I still think Thordsen is the best solution for NY.

 

[fnfalguy]

Have one with a Thorsen. Personally don’t like it. So far my favorite set up is the spur grip with an extended trigger guard. But only my experience with a few different set ups.

 

[dsdmmat]

In my local Gander Outdoors they have the Aero upper and lower also. Plus all the parts kits, barrels, hand guards, BCG and related parts as well as all the furniture. I keep thinking it might be interesting to to a full Gander build and see how it turns out.

Way too much money doing it that way.

 

[Exonautic]

I had an aero m4 lower that I built up but ended up selling. You're supposed to clip a few coils off that spring to get it to fit. It's damn near impossible to otherwise, plus you'd never be able to get the rear takedown out.