The worst LPK I've handled to date

[zachomega]

I try to stick to mid tier name brands when i buy parts.

The first LPK i bought was the cmmg kit which is kind of the gold standard of LPKs.

I've used Anderson, CMC, and most recently Aero Precision.

The Aero Precision LPK is without a doubt, the worst kit i have ever handled.

I used the enhanced m4e1 kit on an Aero Precision m4e1 lower.

If it has a detent, it feels like like trash when you move it.

The takedown detent comes with this tiny set screw. The idea being that if you remove the back plate, your detent spring doesn't go flying. It is extremely difficult to get into the lower. And once you do, there is so much tension on it that you can't actually move the takedown pin. This is such a non issue too. I removed the set screw and will just not lose the spring when I remove the backplate like i have done with every other AR i own.

The safety is the mushiest least positive safety and feels like it is dragging on something when you try to move it. It does function. But i genuinely dislike it enough that I bought another generic safety of unknown manufacture to replace it today because it couldn't be any worse.

I'm just so surprised that this kit sucks this bad when the Anderson kit that costs like 10$ more comes with a trigger and an A2 grip is perfectly fine. The comparable CMC kit is much nicer as well and costs roughly the same.

Did i just get a lemon kit or is Aero Precision's LPK junk?

-Zach

[Xringshooter]

With the set screw under the back plate you need to cut about 4 turns off the spring, it will then go in easier and you won't ever lose the spring if you take the buffer tube off to put something different on.

I've used the Aero LPK a number of times in the past when brought to me by a customer when asked to help them understand how everything goes together on a build they are doing. I would explain the set screw/spring set up and what to do with the spring for it to work correctly.

I've never had any problems such as you are having with the safety. All the ones I've dealt with have been positive stops and worked very smoothly.

Did you happen to compare the safety detent holes/etc. of the Aero and the other one? Just wondering if they just weren't machined/finished correctly.

Don't know what else to say, all the stuff I've bought from Aero over the years has been high quality. Now that said, I haven't bought anything from them in a while (year or so) as I have a good stock of AR bits and pieces.

[markshere2]

I try to stick to mid tier name brands when i buy parts.

The first LPK i bought was the cmmg kit which is kind of the gold standard of LPKs.

I've used Anderson, CMC, and most recently Aero Precision.

The Aero Precision LPK is without a doubt, the worst kit i have ever handled.

I used the enhanced m4e1 kit on an Aero Precision m4e1 lower.

If it has a detent, it feels like like trash when you move it.

The takedown detent comes with this tiny set screw. The idea being that if you remove the back plate, your detent spring doesn't go flying. It is extremely difficult to get into the lower. And once you do, there is so much tension on it that you can't actually move the takedown pin. This is such a non issue too. I removed the set screw and will just not lose the spring when I remove the backplate like i have done with every other AR i own.

The safety is the mushiest least positive safety and feels like it is dragging on something when you try to move it. It does function. But i genuinely dislike it enough that I bought another generic safety of unknown manufacture to replace it today because it couldn't be any worse.

I'm just so surprised that this kit sucks this bad when the Anderson kit that costs like 10$ more comes with a trigger and an A2 grip is perfectly fine. The comparable CMC kit is much nicer as well and costs roughly the same.

Did i just get a lemon kit or is Aero Precision's LPK junk?

-Zach

Cut the spring down a few turns.

Worked for me.

[zachomega]

I could cut the spring down. But why would they make a kit specifically for this type of lower without a precut spring?

The bigger issue with this kit is the safety is mushy and not positive. I still haven't removed it yet to see what is going on in but i will when the new safety arrives.

-Zach

[wanneroo]

I did a Aero LPK recently and I thought it better than the Palmetto parts I used before.

[zachomega]

i had a complete cmmg kit so i pulled the safety, detent, and spring. The TiN finish on the detent was nearly all gone. Mind you, i haven't even shot the rifle yet.

The safety itself looked... Okay? Like it needs to be cleaned. But the actual path for the detent looks okay.

All are in a bag.

New safety installed. It is better. Still not amazing. But a lot better than it was.

Also, it is a real pain in the ass to remove and install a safety with a hiperfire trigger if you don't remove it... But it can be done.

-Zach

[zachomega]

I did a Aero LPK recently and I thought it better than the Palmetto parts I used before.

The only PSA part i have is a NiB trigger i received in a trade. It is functional, but i have better triggers in all but one of my lowers. And even that one will get something nicer. I just bought it last week. I have a Larue 2 stage trigger that is probably going to end up in it.

-Zach

[Xringshooter]

I could cut the spring down. But why would they make a kit specifically for this type of lower without a precut spring ... -Zach

Probably cost and ease of putting the kit together. They probably buy a bazillion of the springs at a time and to have a manufacturer make a special one might cost a bit more. The cost to buy a bazillion shorter springs really couldn't cost more than a couple pennies per spring if even that. Only other thing that comes to mind is if someone without an Aero lower bought the kit and put it in an Anderson lower, the shorter spring and detent wouldn't work as good and you might lose a takedown pin at an inopportune time because the detent isn't holding the pin tight enough.

That said, I agree with you and they could, if they wanted, package two different LPK's. One for generic lowers (long spring) nd one for lowers that have the threaded hole (short spring). But then some doofus would order the wrong one, lose a takedown pin and rant and rave over the internet about how bad Aero is for selling defective products. But Aero could include a note with the LPK telling people to shorten the spring if they are going to use the set screw option.

[Jhaydeno]

I always *polish* the detent pins on some 400-600 grit sandpaper. No manufacturer makes the smooth, and most have points that catch and drag. As for the safety, it sounds like you may need a little more spring.

[zachomega]

Probably cost and ease of putting the kit together. They probably buy a bazillion of the springs at a time and to have a manufacturer make a special one might cost a bit more. The cost to buy a bazillion shorter springs really couldn't cost more than a couple pennies per spring if even that. Only other thing that comes to mind is if someone without an Aero lower bought the kit and put it in an Anderson lower, the shorter spring and detent wouldn't work as good and you might lose a takedown pin at an inopportune time because the detent isn't holding the pin tight enough.

That said, I agree with you and they could, if they wanted, package two different LPK's. One for generic lowers (long spring) nd one for lowers that have the threaded hole (short spring). But then some doofus would order the wrong one, lose a takedown pin and rant and rave over the internet about how bad Aero is for selling defective products. But Aero could include a note with the LPK telling people to shorten the spring if they are going to use the set screw option.

Or just include two springs. It is neither a budget nor top end kit. But as you stated, the springs can't be that expensive.

I always *polish* the detent pins on some 400-600 grit sandpaper. No manufacturer makes the smooth, and most have points that catch and drag. As for the safety, it sounds like you may need a little more spring.

Interesting about polishing off the point. So you round the tip of the detent over?

I was reading last night and it also suggested more spring pressure to give a more positive click.

To be fair to my previous complaint and knowing that grips vary in how deep the springs sit, i tried a factory a2 and a bcm mod 3. Both felt pretty much the same.

I've heard some people use detents as a shim in the grip. I might give that a try. Then i can cut down the spring to size.

-Zach