New Aero Precision M5 .308 build. Help?

[IronMonster]

Well I took the plunge, went down to Surplus Arms & Ammo and bought a Aero M5 lower. I have never owned a .308 AR let alone built one. I kind of expected it to be like building a AR15 but I can say so far its been nothing like that.

So I bought the lower, I plan on using a CMC trigger so I really dont want to buy a entire LPK for the thing since all I really need are the takedown pins and mag release. Aero sells those separate but the long pin is out of stock. I plan on using a Aero upper, I figured at least having those two match would alleviate any worries about compatibility. I was told that the standard DPMS pins will work but the rear is a little short, It does not seem like anyone but Aero sells the Aero pins.

I started looking around at BCG and barrels, Which If I can I would like to buy from the same manufacture (that way if there is a headspace issue I know they will take care of it) It seems like BCG vary wildly in price for comparable features. A PSA Nitride BCG is $149 VS a DPMS phosphate @ $289 both made from 9310

I might opt for a Rainer Arms barrel, They are 3 miles from my shop and I hear they will check headspace with one of their barrels free of charge when you buy the barrel. The 18" Black Select is $279 and instock. I hate to buy there BCG though as it is twice what the PSA one is and is made from the same stuff.

Aero's Buffer, spring and tube set is not in stock. I am leaning towards using a PWS enhanced buffer tube I have but will still need to source a buffer and spring.

A rail seems to be the hardest thing to determine if it will work The Aero says it is a DPMS High (.210) profile. I would like a slim Keymod rail something like the KMR The only one I have found is the Odinworks but they list two options 2.0 and 2.06 and the Aero says 2.10 so I am assuming they will not work, They 15" is out of stock anyway.

Anyway now that I have taken the plunge it seems like its a little stressful trying to determine what's what and if all the bits will work together. I am in no real hurry but I would like to get some parts coming to at least get the lower together and start figuring out the rest of the bits.

Anyone have some insight or suggestions ?

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[mjbskwim]

This would have been my post if I would have tried a 308 build. The very reason I didn't start.
But you have to look at it as a rifle build not a big AR build.I mean how many different brand rifles use the same parts? There are a few but most don't
If I was going to build one I would stick with one vendor and have them make sure the parts will work or take them back.Especially if they were close by like RA is.
Good Luck!

 

[jluck]

Is it too late to take back the Aero stuff and go with Mega monolithic? That's how I'm going too build one too basically lay the foundation. Still a local company also right?

 

[IronMonster]

Yep, after stressing for a couple days I just ordered the barrel, upper with hand guard and the BCG from Aero. It added a bit to the cost but I figured that way I basically have a Aero rifle and it's still $200 cheaper than the rifle they sell and mine will have a better trigger and furniture I prefer. I think it will work out.

 

[IronMonster]

The Mega stuff is beautiful but twice the cost and solves none of the issues I have ;-)

I went down and fondled a Rainer/Mega at Rainer Arms. Super sweet but at $2700 it's right at twice what I'll have in a complete rifle.

I'd love to have the Mega but for what I want the rifle for $2700 seems silly.

 

[spectra]

Well IM since you are so close to Rainier I would say yes on the barrel and try and get a BCG before so you can have it head spaced. My choice would be this one <broken link removed> I had one in the past with a Rainier barrel and they worked great together. Now on to the rail well once again Rainier http://www.rainierarms.com/fortis-switchtm-308-rail-14 I just like the way it looks and would go bigger but they are out of stock right now.

I like PSA stuff but have not heard good things on the 308 stuff yet. People have been having issues with parts not fitting if it was not a 100% PSA build.

Good luck with the build they are fun.

 

[spectra]

Yep, after stressing for a couple days I just ordered the barrel, upper with hand guard and the BCG from Aero. It added a bit to the cost but I figured that way I basically have a Aero rifle and it's still $200 cheaper than the rifle they sell and mine will have a better trigger and furniture I prefer. I think it will work out.

Looks like you got it handled

 

[jluck]

The Mega stuff is beautiful but twice the cost and solves none of the issues I have ;-)

I went down and fondled a Rainer/Mega at Rainer Arms. Super sweet but at $2700 it's right at twice what I'll have in a complete rifle.

I'd love to have the Mega but for what I want the rifle for $2700 seems silly.

Copy. I thought the upper/lower combo came with pins and a HG.

 

[spectra]

Copy. I thought the upper/lower combo came with pins and a HG.

Yes the Mega MaTen Key Mod set comes that way. You also just need a normal AR15 LPK also to put it together. Price is down to about 750.00 on them plus shipping and transfer.

 

[IronMonster]

Copy. I thought the upper/lower combo came with pins and a HG.

They might, however I was not smart enough to order them as a combo

 

[spectra]

So what barrel did you end up with? Normal BCG or did you go special on it?

 

[IronMonster]

<broken link removed>


Standard BCG with FA notches

 

[IronMonster]

I have made some progress. I am still lacking the bolt catch and I bought some DPMS pins and the pivot pin is not so bueno. I also used a AR15 mag catch which is not gonna fly but I have a AR10 one on order. So I have a Tubbs LR308 flat coil spring, A DPMS .308 buffer. A CMC 3.5 lb single stage flat trigger. A Battle Arm's Ambi safety and the Magpul furniture. I got a conformation that my upper and rail shipped, still no word on the BCG and barrel. I think I have or have on order everything its gonna take to finish her. I am getting excited to see if it will run

 

[IronMonster]

I got a few more bits, upper and rail showed today as well as the bolt catch. Starting to resemble a rifle

 

[spectra]

I love the UBR and hopefully it will help level out the 308. I know they can be heavy on a 5.56. Looks good I am sure you will enjoy it!

 

[Daniel Dyk]

How did your build end up? I am in the process of getting my parts together right now to build my first 308 as well. You aren't lying when you say things are different and hard to find. I have an Aero upper and lower but am trying to decide on my rail right now. I'm going with a black hole weaponry barrel and an SAA Nickel boron BCG. I was thinking about going with the Rainier arms SWITCH Rail but I'm not sure it will fit yet. I emailed Rainier to find out tonight.

 

[2A2Dend]

@IronMonster
Your thread is conveniently timed. I ordered the Aero Precision M5 Builders Kit last night.

How has your building treated you?
The AR platform 308 will be my first venture

 

[clearconscience]

I built an Aero M5 .308 recently for a hunting rifle. I have to say I love it.
Aero makes a quality product and a great price.

 

[Joe13]

Wow - just Wow!!!

I can't believe you don't already have a dozen of these!!!!


Good luck on the build - if anyone can piece one together it will be you IM.

 

[Flopsweat]

Wow - just Wow!!!

I can't believe you don't already have a dozen of these!!!!


Good luck on the build - if anyone can piece one together it will be you IM.

Well, since the last time he posted in this thread was in 2015, I'm betting he's already completed it.