AR 308 receiver - what's the best?

[Smitty192]

At the risk of beating of beating a dead horse...

I am venturing off to have a 308 gas gun built. It will be used for some local matches with a maximum distance of 600 yards. I have picked and up a used Aero Precision M5 receiver set that I was going to use that as my starting point. I have found myself with some additional funds and I'm starting to rethink that plan. Is there a better option that will yield more potential accuracy? How much does the receiver factor into the overall accuracy equation? Or is it simply a function of good is good enough?

Thanks in advance.

 

[hlee]

You'll get some very spendy replies, I am sure. I'd venture that you will be more than happy with your Aero set. I've build a couple of AR-15s on the much maligned Anderson manufacturing receivers and they have been very accurate guns.

 

[pugnado]

The Aero Precision M5 Receiver Set is a great set, I have the M5 on my AR10 and the M4E1 on my 300 blackout pistol.

Here's why:

If you buy an upper with the forward assist installed, you don't need to drive any roll pins into it.
The lower has a threaded bolt catch pin and an integrated trigger guard, so no pounding stuff into it either.

The lower also has a nylon tipped tensioner screw beneath the grip that engages the takedown pin tab on the upper and keeps stuff tight.
(On the M4E1, the hole for the takedown pin retaining pin & spring is threaded and their LPK comes with a tiny set screw for it, so you don't have to play stupid games trying to find launched springs when working with the castle nut/buffer tube endplate etc...)

308 AR's are kind of a bitch sometimes due to not being 'milspec', with AP you can buy their M5 LPK without the trigger and grip for cheap and it'll just work, nothing too big or small.

Their Atlas R-one and S-one series handguards are great too as long as you have low profile gas block, they're slim and tight (important for big heavy AR10) and no need to worry about mismatched rail heights.

Tip: Don't buy anything from AP's website. Way overpriced, even with their %20 off daily spam/emails.
Check out Brownells + Activejunky for a %14 savings on already discounted prices.
Also install the 'Honey' plugin into Chrome and use that to find secret coupon codes on OpticsPlanet that get you a similar deal + free shipping.

Tip 2: Buy the upper and lower as a set, they'll fit better if they're part of the same production run.

 

[Smitty192]

The Aero Precision M5 Receiver Set is a great set, I have the M5 on my AR10 and the M4E1 on my 300 blackout pistol.

Here's why:

If you buy an upper with the forward assist installed, you don't need to drive any roll pins into it.
The lower has a threaded bolt catch pin and an integrated trigger guard, so no pounding stuff into it either.

The lower also has a nylon tipped tensioner screw beneath the grip that engages the takedown pin tab on the upper and keeps stuff tight.
(On the M4E1, the hole for the takedown pin retaining pin & spring is threaded and their LPK comes with a tiny set screw for it, so you don't have to play stupid games trying to find launched springs when working with the castle nut/buffer tube endplate etc...)

308 AR's are kind of a bitch sometimes due to not being 'milspec', with AP you can buy their M5 LPK without the trigger and grip for cheap and it'll just work, nothing too big or small.

Their Atlas R-one and S-one series handguards are great too as long as you have low profile gas block, they're slim and tight (important for big heavy AR10) and no need to worry about mismatched rail heights.

Tip: Don't buy anything from AP's website. Way overpriced, even with their %20 off daily spam/emails.
Check out Brownells + Activejunky for a %14 savings on already discounted prices.
Also install the 'Honey' plugin into Chrome and use that to find secret coupon codes on OpticsPlanet that get you a similar deal + free shipping.

Tip 2: Buy the upper and lower as a set, they'll fit better if they're part of the same production run.

Thanks for the tip and information.

 

[jda2631]

Schuyler arms also has some great deals too, smaller inventory so it's kinda hit or miss on what they have at the time or whats on sale. But I got an Aero M5 FDE stripped upper and lower receiver set for $205 shipped a few months ago.

 

[hitman]

I asked Craddock the same question and he gave the same answer actually. Said he always had the best luck with Aero sets. For the prices they cannot be beat. I have several for small frames and one for the large but I picked up an LMT so not going to use it but I love their sets I have used.

 

[VJJPunisher]

Radical firearms is by far the best

 

[schlaiek]

Aero is great, especially for the money
If you are going for a super lightweight build look at the 2A set. Upper & lower are right at 16oz - about half the weight of the aero set.

 

[Landon4]

I’ve got a Next level armament upper and lower set as well as their dlc coated bolt, it’s been a great gun I’ve made hits out to 1350yds, it’s chambered in 6.5 creed

 

[akg102]

Lots of options --

V7, 2A, Zev/Mega, CMT. Aero is good for the price.

With that said, your choice of barrel is going to be the most important. Get a quality receiver set and the best barrel you can afford.

 

[_Windrider_]

A quality receiver shouldn’t require shims or nylon screws to tighten it up. If it does, I would look elsewhere if you want the best accuracy possible. I recently bought a Zev and I am extremely impressed. Machining is perfect and there is zero slop in the upper/lower and guess what.....no nylon screws either. Now i realize these are expensive, but you get what you pay for. All of the options mentioned are good to go. You just have to decide what kind of results you want and how much you are willing to pay for it.

 

[Smitty192]

Lots of options --

V7, 2A, Zev/Mega, CMT. Aero is good for the price.

With that said, your choice of barrel is going to be the most important. Get a quality receiver set and the best barrel you can afford.

That's kinda what I thought. The barrel is going to be the area where I'll invest the most money. I really wasn't sure how much a receiver set played in the equation. Thanks for the feedback.

 

[Smitty192]

A quality receiver shouldn’t require shims or nylon screws to tighten it up. If it does, I would look elsewhere if you want the best accuracy possible. I recently bought a Zev and I am extremely impressed. Machining is perfect and there is zero slop in the upper/lower and guess what.....no nylon screws either. Now i realize these are expensive, but you get what you pay for. All of the options mentioned are good to go. You just have to decide what kind of results you want and how much you are willing to pay for it.

Good feedback on the Zev. I haven't been able to find much in the way of reviews on them. They certainly look slick.

 

[Velocity Chad]

Zev bought mega which had a very good reputation. I've never actually held a zev in my hands to compare. Aero is my go to set up for most receivers. Good quality and reasonable priced.

 

[Blinks711]

The Aero sets are a great deal for the price. I also really like Mega(now Zev) and the fit and finish is great. Also the Seekins builders sets are pretty nice but you are stepping up a bit on the price ladder.

 

[_Windrider_]

Zev bought mega which had a very good reputation. I've never actually held a zev in my hands to compare. Aero is my go to set up for most receivers. Good quality and reasonable priced.

The zev receivers are made in Washington at the old mega facility.

 

[hypno02]

I find it hard to believe anything would be better than the new LMT MARS-H

 

[_Windrider_]

I find it hard to believe anything would be better than the new LMT MARS-H

The only problem is the Handguard is proprietary and short

 

[hypno02]

The only problem is the Handguard is proprietary and short

I misread OP's post. I was thinking lower only.

In regards to the LMT upper receiver in this case proprietary IMO is a good thing. You have the strongest upper receiver/rail on the market (which itself carries several advantages), more optic mounting solutions due to an upper receiver not 'ending,' and the quick change barrel capability. Sick of shooting .308? 30 Seconds later--Wha-la! you now have a 6.5creed/.260/7-08/.243.

The only downside is the heavy barrel extension. But the lightweight barrel with the aluminum extension resolves this issue.

I don't consider upper length to be a downside as I feel it's completely adequate. I'll take the robustness of the LMT design over the length of a generic 15" rail. Just my opinion.

 

[_Windrider_]

I misread OP's post. I was thinking lower only.

In regards to the LMT upper receiver in this case proprietary IMO is a good thing. You have the strongest upper receiver/rail on the market (which itself carries several advantages), more optic mounting solutions due to an upper receiver not 'ending,' and the quick change barrel capability. Sick of shooting .308? 30 Seconds later--Wha-la! you now have a 6.5creed/.260/7-08/.243.

The only downside is the heavy barrel extension. But the lightweight barrel with the aluminum extension resolves this issue.

I don't consider upper length to be a downside as I feel it's completely adequate. I'll take the robustness of the LMT design over the length of a generic 15" rail. Just my opinion.

I looked real hard at the LMT before I bought the Zev. In the end I opted for the 17” Handguard of the Zev. However, I did buy the lower parts kit from LMT.

 

[AUXIN]

Got a great deal on a zev set and rail. Fit and finish is what you would expect from Mega before the merger. I’m really enjoying it.

 

[DRAM40A1]

I believe Midwest PX still has Mega Maten sets.

 

[akg102]

I recently did a build based around the new Zev receiver set -- fit, finish, and options appear to be every bit as good as the previous Mega Maten builds I've completed. One advantage is that the Zev 308 handguard is the same diameter as that of an AR15. If nothing else, it provides a bit of uniformity in feel to the platform.

 

[Waorani]

AP 308 upper/lower - $200 (+10% off that w/ code FN5) at Brownells https://www.brownells.com/manufacturers/aero+precision/index.htm?utm_medium=email&utm_source=marketo&utm_campaign=2019_02_16_aero&utm_content=rifle&mkt_tok=eyJpIjoiT0RJelkyRTRNV1F3T0RnMiIsInQiOiJJcVwvQUV1SGhTRDBLOFE1TlkydTVZZFNRZndiK0xPckNVemRMQ3BSc3M2SmJoXC9BWXk5TjRXUnpmVnI1ZTNTMnlqWm1Gem02eTJzekVKSU5UM2Y3alNqdEtWMGNiMUhUcEd1c2xpK3R3UkloXC9DUzYycktpWlpBVnlEdEZUXC90SmMifQ==

 

[Smitty192]

Got a great deal on a zev set and rail. Fit and finish is what you would expect from Mega before the merger. I’m really enjoying it.

That's good to hear. I certainly do like the looks of them.

AP 308 upper/lower - $200 (+10% off that w/ code FN5) at Brownells https://www.brownells.com/manufacturers/aero+precision/index.htm?utm_medium=email&utm_source=marketo&utm_campaign=2019_02_16_aero&utm_content=rifle&mkt_tok=eyJpIjoiT0RJelkyRTRNV1F3T0RnMiIsInQiOiJJcVwvQUV1SGhTRDBLOFE1TlkydTVZZFNRZndiK0xPckNVemRMQ3BSc3M2SmJoXC9BWXk5TjRXUnpmVnI1ZTNTMnlqWm1Gem02eTJzekVKSU5UM2Y3alNqdEtWMGNiMUhUcEd1c2xpK3R3UkloXC9DUzYycktpWlpBVnlEdEZUXC90SmMifQ==

Thanks. Those are pretty good deals!

 

[Potss]

Seekins set is pretty awesome too.

 

[davsco]

see if jse surplus has any mega upper/lower/handrail sets left, that's where and what i got for my ar-10 build, real nice stuff!

 

[Dschapp44]

If you can go with the Mega Maten set then do it, otherwise the price on those Area M5s are hard to beat. The internal barrel nut is a great design and the quality is top notch. I think you can expect the same quality from Zev but i prefer the older Mega sets. I just bought an extra lower from G & S tactical so they still have new stuff out there.

 

[_Windrider_]

If you can go with the Mega Maten set then do it, otherwise the price on those Area M5s are hard to beat. The internal barrel nut is a great design and the quality is top notch. I think you can expect the same quality from Zev but i prefer the older Mega sets. I just bought an extra lower from G & S tactical so they still have new stuff out there.

The Zev receivers are made at the old Mega factory by mega employees on mega machinery. I can say without a doubt the quality is top notch.

 

[Dschapp44]

I don't doubt that at all. I just looked again and couldn't find the internal barrel nut upper/handguard set. Do you know why they stopped making those?

 

[_Windrider_]

I don't doubt that at all. I just looked again and couldn't find the internal barrel nut upper/handguard set. Do you know why they stopped making those?

Nope. But I did get some indication from them that the Mega line might be coming back, although probably not under that name. Pure speculation and nothing firm.

 

[Dschapp44]

Interesting and I hope it does. Those were my favorite receiver sets to use.

 

[Greg Langelius *]

I have a question concerning slop between the Upper and Lower that's generating this bunch of discussion and solutions.

I wonder whether the problem is more about aesthetics, or whether the slop actually translates into an accuracy issue. Personally, I could care less about slop so long as the rifle's accuracy isn't actually impaired by its presence.

I have built a 16" Franken-AR15 from a motley collection of parts that were (at the time) the absolutely cheapest parts available from Amazon (except for a Stag Model 3 Barrel). It shoots great, looks a tad odd. The main lesson learned from that build was that I really prefer to either buy a complete rifle, or at least a complete rifle kit.

In my case, "best" translates into a simple build that delivers a reasonably accurate rifle without going deep into the Kitty; 1 MOA would be good enough, better would be excellent.

My goal is a reasonable degree of accuracy to 600yd, predicated on either FGMM 168 or IMI 168 Semi-Auto Match, or a handload delivering similar velocity (nominally 2630-2650fps) with the 168 FMJBT Match bullet. I specifically intend to mount the Bushnell Drop Zone 308 BDC scope that works very well for me with the noted ammunition.

I am also tempted to use this Upper.

If I ever decide to build an AR for 1000yd, it will be a 260.

So in the context of this thread, what would my parts list look like?

Greg

 

[GhostFace]

AR10 Matrix Aerospace Three Piece Kit

This three piece kit includes a brand new Matrix Aerospace AR10 Lower Receiver, Upper Receiver and Keymod Handguard. Built to the same specs as Ruger! All matte black finished parts, includes barrel nut.

www.chandlerhardwoods.com

If i were building i would use them for my base.

 

[flyer]

There are things much more critical to a large frame AR receiver than upper to lower fit.

Free floating a barrel is critical for accuracy but if you load the rifle hard, the barrel nut/handguard junction is going to make a difference in the alignment between the barrel and upper receiver rail.

A bit of slop between the upper and lower just rattles a bit until you load up.

If the rattle bothers you, you can get oversize pins and ream it to fit but the BCG will still rattle inside the upper if you shake it.

Today Aero has a special on an M5E1 enhanced upper and lower with an M-lok tube handguard for $299. This has an inverted barrel nut setup and the tube handguard bolts directly to the upper receiver snout. It's going to fit upper to lower pretty well, a little rattle, not much but the inverted barrel nut is going to keep your optics lined up with your barrel when you load it hard.

That's a pretty good price. Throw in an Aero LPK and stop worrying about it.

Some might be cheaper but only if you skimp on the handguard.

 

[The King]

Spend your new found gains on a proof barrel.

 

[Greg Langelius *]

Thank you folks for your useful advice.

I have looked at the M5E1 offer and it's very tempting. I may not be able to fit the purchase into the budget before the offer ends. But I suspect it will still be a worthwhile purchase even if I miss the deadline; effectiveness trumps price, IMHO.

I tend to put my money into the barrel first and foremost, and have been following L-W barrels for some time now. The 28" L-W .260 barrel I put on my Savage rebuild in 2003-ish transformed the rifle, and is still shooting especially well these days on a sparing basis.

Greg

 

[The King]

Good point Greg. Lothar Walther (spelled out for folks here who haven’t been on the hide since Genesis like we have) was THE barrel that the Larue OBR built its reputation on.

I have been shooting the Proof barrels for the last few years as I carry a rifle a lot and the extra pound of weight loss means something to me.

Thank you folks for your useful advice.

I have looked at the M5E1 offer and it's very tempting. I may not be able to fit the purchase into the budget before the offer ends. But I suspect it will still be a worthwhile purchase even if I miss the deadline; effectiveness trumps price, IMHO.

I tend to put my money into the barrel first and foremost, and have been following L-W barrels for some time now. The 28" L-W .260 barrel I put on my Savage rebuild in 2003-ish transformed the rifle, and is still shooting especially well these days on a sparing basis.

Greg

 

[Greg Langelius *]

Yes, I've been looking at the Proof stuff. Very interesting, but then there's the price.

I keep hearing about (and recently handling) the AR-10 and there's an apparently a significant weight issue with which the Proof barrel concept could be helpful. My present health condition has me down around 150lb, and I'm apparently never going to become my dream as a modern day Charles Atlas. Being a 195lb Marine Recruit Depot graduate is a fond but futile memory.

I suspect that because I want the 308 in order to get good 800(+?)yd performance, a minimum barrel length should be about 20", and that's a reluctant minimum. Those who now me better understand that I am a fool for the 24" (and even 28") barrel length.

So Proof could be a helpful option. I'm going to be breaking that bank with this one anyway, so a bit of a stretch to glom onto a Proof may just be warranted.

Greg

 

[bfoosh006]

I have a question concerning slop between the Upper and Lower that's generating this bunch of discussion and solutions.

I wonder whether the problem is more about aesthetics, or whether the slop actually translates into an accuracy issue. Personally, I could care less about slop so long as the rifle's accuracy isn't actually impaired by its presence.

I have built a 16" Franken-AR15 from a motley collection of parts that were (at the time) the absolutely cheapest parts available from Amazon (except for a Stag Model 3 Barrel). It shoots great, looks a tad odd. The main lesson learned from that build was that I really prefer to either buy a complete rifle, or at least a complete rifle kit.

In my case, "best" translates into a simple build that delivers a reasonably accurate rifle without going deep into the Kitty; 1 MOA would be good enough, better would be excellent.

My goal is a reasonable degree of accuracy to 600yd, predicated on either FGMM 168 or IMI 168 Semi-Auto Match, or a handload delivering similar velocity (nominally 2630-2650fps) with the 168 FMJBT Match bullet. I specifically intend to mount the Bushnell Drop Zone 308 BDC scope that works very well for me with the noted ammunition.

I am also tempted to use this Upper.

If I ever decide to build an AR for 1000yd, it will be a 260.

So in the context of this thread, what would my parts list look like?

Greg

In context to the slop... I believe minimizing the slop allows the shooter to not need to focus on how they hold the AR / sling up the AR as much when compared to it being sloppy.

When I have tightened up the slop, and fired from the bench.. even then I don't have to think about if that flyer is from the slop or was me.

Others will disagree about it mattering, but for me I think it helps to have a snug fitting upper and lower.

Another thing I "harp" about is Lapping the upper receiver face true. It has helped my groups be more consistent and improved accuracy in one before and after test I did.. .. and I end up doing it to ever AR upper now. My results were, IMHO, dramatically improved.

Anyone interested in the thread.. just IM me, and I will send the link.