Suggestions for a “Do It All” Lower Configuration?

[jab00]

I’m hoping that you guys can help me build a “do it all” AR15 lower. I’m basically looking to build a lower that I can swap between a few uppers instead of buying a lower for each of them.

IlI’m really looking for is some advice on a buttstock / grip / trigger combo that will work on an 20” upper that I’m using prone for shooting groups at 300 and a 16” upper to shoot steel and general plinking. Ive got a Magpul fixed rifle stock on my current lower but I’d like to know what other options I should consider

The biggest restriction that I have on the set up is that collapsible stocks are a no-go for me.

 

[DRAM40A1]

Magpul Gen 2 UBR
Geissele SSA-E
BCM Gunfighter grip

 

[DRAM40A1]

Why is a collapsible stock a no go? The UBR adjust for length but is built completely different than other collapsible stocks.

 

[The DFC]

Why is a collapsible stock a no go? The UBR adjust for length but is built completely different than other collapsible stocks.

Does it fit on a carbine tube?

 

[jab00]

Why is a collapsible stock a no go? The UBR adjust for length but is built completely different than other collapsible stocks.

New Jersey requires that stocks be pinned. "adjustable" is okay (like the Magpul PRS) but I'd have to permanently fix an UBR into one position. The UBR could be an option if I could find the "sweet spot" position that would give me a decent cheek position laying prone and standing

 

[DRAM40A1]

Does it fit on a carbine tube?

No, the UBR has a proprietary receiver extension.

 

[DRAM40A1]

Here’s a photo from the bottom with the buttstock removed. It’s a great option for both carbine and rifle.

 

[jab00]

Here’s a photo from the bottom with the buttstock removed. It’s a great option for both carbine and rifle.

The UBR might be a good option for me. I’d just need to figure out a good position to pin it. I’m also looking at the B5 SOPMOD as another choice

 

[DRAM40A1]

You would have to pin this one too but it’s a Magpul ACS and this lower gets used on a 22” 224 Valkyrie, a 12.5” 5.56 and a 10.5” 300 Blackout. Yes, I have a tax stamp.

 

[MontanaMan]

I’m also looking at the B5 SOPMOD as another choice

They make 2 versions..............the "enhanced" version is the one you want & it's the more expensive of the 2; it's a virtual dupe of the LMT SOPMOD. SOPMOD is a very good all around stock.

The UBR is also a great stock, IMO, but it's heavy, even the GEN 2 version.

MM

 

[bfoosh006]

While I am not giving you an answer to the buttstock portion... ( sounds like you already have that figured out )

I do suggest a quality 2 stage trigger... Geissele SSA-E, LaRue MBT ( second choice only because the trigger bow edges should, IMHO, be more rounded off )
I good 2 stage trigger is far easier to back off of a shoot , then a single stage AR trigger.

Grips are highly dependent on your hand size.... smaller hands, the LaRue A-Peg is a good one ... large hand size, The Ergo Tactical Deluxe is about as big as they get.

I will add... strongly consider a ambi lower... I love my RA ambi's
https://www.rainierarms.com/rainier-arms-ultramatch-billet-ambi-lower-receiver-mod-3/

 

[DRAM40A1]

I’m not trying to brag but it doesn’t get much better than this....KAC ambi receiver, LMT SOPMOD, BCM Gunfighter grip and KAC 2 stage trigger ?

 

[jab00]

While I am not giving you an answer to the buttstock portion... ( sounds like you already have that figured out )

I do suggest a quality 2 stage trigger... Geissele SSA-E, LaRue MBT ( second choice only because the trigger bow edges should, IMHO, be more rounded off )
I good 2 stage trigger is far easier to back off of a shoot , then a single stage AR trigger.

Grips are highly dependent on your hand size.... smaller hands, the LaRue A-Peg is a good one ... large hand size, The Ergo Tactical Deluxe is about as big as they get.

I will add... strongly consider a ambi lower... I love my RA ambi's
https://www.rainierarms.com/rainier-arms-ultramatch-billet-ambi-lower-receiver-mod-3/

The SSA-E is on the top of my list at the moment for triggers

 

[The DFC]

FWIW LMT has a DMR stock that will fit a carbine tube in both ar10 and ar15 platforms. I've had it a few weeks on my 24" LMT 6.5creedmoor tank of a gun and it works really well once I got it dialed in-which was more of me being a dumbass and less of the stock's fault. It has 3 positions it moves on the tube as well as the comb and stock extension. Usual LMT quality-and price.

 

[The DFC]

I’m not trying to brag but it doesn’t get much better than this....KAC ambi receiver, LMT SOPMOD, BCM Gunfighter grip and KAC 2 stage trigger ?

I pretty much agree-but having a Krieger barrel-like my LPR has-adds at least 1" to the end of my boner

 

[DRAM40A1]

I pretty much agree-but having a Krieger barrel-like my LPR has-adds at least 1" to the end of my boner

I hear ya. I have Rock Creek, Bartlein and Kreiger. But, none of them are hanging on a KAC. They are all large frame though. I want an SR-25 so bad right now!

 

[The DFC]

I hear ya. I have Rock Creek, Bartlein and Kreiger. But, none of them are hanging on a KAC. They are all large frame though. I want an SR-25 so bad right now!

Do you know what barrel KAC uses in SR25 stainless version?

 

[DRAM40A1]

Do you know what barrel KAC uses in SR25 stainless version?

Yes
I’m just saying that none of mine are on a KAC but I do want one.

 

[VegasHKShooter]

The only issue with the LMT SOPMOD, and I think the B5 as well is: when shooting off of a rear bag, like a Gamechanger, my stock is constantly closing on me. The bag hits the button on the bottom, and closes the stock on recoil. Plays hell with groups. ?
Bad location for that lever for any DMR/SPR gun’s that will be shot prone and bagged.

 

[jab00]

The only issue with the LMT SOPMOD, and I think the B5 as well is: when shooting off of a rear bag, like a Gamechanger, my stock is constantly closing on me. The bag hits the button on the bottom, and closes the stock on recoil. Plays hell with groups. ?
Bad location for that lever for any DMR/SPR gun’s that will be shot prone and bagged.

New Jersey has found the solution to the problem of the stock closing accidentally by requiring it to be permanently pinned in one position.

 

[flyer]

I like both the Magpul MOE FCS (fixed carbine stock) and the Strike Industries Viper Modular fixed stock. The Strike is heavier and more solid, the Magpul is cheaper and still more solid than a typical carbine stock (pinning might change that).

The deeper question is will all of your uppers work with the same buffer?

A Vltor A5 setup might be worth looking at if anything needs a heavy buffer. In that case, I always suggest the POF P308 7 position buffer tube as a good value AR10/A5 length carbine buffer tube.

I really like the Tango Down Battle Grip, it has a nice rubberized surface with an ergonomic shape, no finger grooves and a waterproof storage compartment. When I can have a pistol grip, I choose that one.

I hope to try an inexpensive Sig ambidextrous safety soon, it's on order. I have a Troy that is nice but their company politics are questionable and I have a cheapo thread on lever style which I'm worried is going to back out. The Sig is cheaper and the lever is held on with a pin so less worry about losing it.

I like using inexpensive drop-in match triggers like the Larue MBT or a Rise RA 140. I always skip the RRA NM 2 stage because it is known to wear out and malfunction quickly.

The rest is pretty straight up LPK parts with the detent ends rounded and polished to eliminate the need for break in.

All of my AR lowers are some variation on that theme. It works for me and isn't too expensive.

 

[jab00]

I like both the Magpul MOE FCS (fixed carbine stock) and the Strike Industries Viper Modular fixed stock. The Strike is heavier and more solid, the Magpul is cheaper and still more solid than a typical carbine stock (pinning might change that).

The deeper question is will all of your uppers work with the same buffer?

A Vltor A5 setup might be worth looking at if anything needs a heavy buffer. In that case, I always suggest the POF P308 7 position buffer tube as a good value AR10/A5 length carbine buffer tube.

I really like the Tango Down Battle Grip, it has a nice rubberized surface with an ergonomic shape, no finger grooves and a waterproof storage compartment. When I can have a pistol grip, I choose that one.

I hope to try an inexpensive Sig ambidextrous safety soon, it's on order. I have a Troy that is nice but their company politics are questionable and I have a cheapo thread on lever style which I'm worried is going to back out. The Sig is cheaper and the lever is held on with a pin so less worry about losing it.

I like using inexpensive drop-in match triggers like the Larue MBT or a Rise RA 140. I always skip the RRA NM 2 stage because it is known to wear out and malfunction quickly.

The rest is pretty straight up LPK parts with the detent ends rounded and polished to eliminate the need for break in.

All of my AR lowers are some variation on that theme. It works for me and isn't too expensive.

So far, all of my uppers seem to work okay with my current H buffer. The only one that’s a question mark at the moment (because I haven’t shot it yet, is a rifle length gas system varmint barrel upper that I just built. I’m hoping to try it this weekend

 

[hlee]

All of my ARs have Gieselle triggers. If I had to pick one, it would be the SDE.

I wouldn't get too wrapped around the axle about the stock if you are forced to pin a collapsible stock anyway. The A2 stock is the length it is for a reason...

As to grips, I like the BCM gunfighter mod3.

 

[jab00]

All of my ARs have Gieselle triggers. If I had to pick one, it would be the SDE.

I wouldn't get too wrapped around the axle about the stock if you are forced to pin a collapsible stock anyway. The A2 stock is the length it is for a reason...

As to grips, I like the BCM gunfighter mod3.

Good point - to be honest, with all of the “new hotness” stocks available nowadays I kind of forgot about the A2

 

[flyer]

For what it is, A2 stocks are expensive. You would think the buffer tube would be very cheap because there is no rib with stock position notches. The plastics should be cheap too.

A2 style handguards are dirt cheap, I'm not sure why the stock didn't follow.

 

[hypno02]

If I could only have one lower it would be the following:

-LMT MARS w/ aluminum enhanced trigger guard
-Geissele SSA-E
-BCM Mod3 grip
-Sopmod buttstock. (Substitute ACS if for precision rifle)

 

[gro]

I have really liked the magpul ACS-L stock, it is a little narrower than the ACS so it feels like I can get level behind the scope easier with my big fat beard face.

I have really liked ADM lowers, they are fully ambidextrous, with bolt lock and release, not just bolt release like KAC and POF.

Any geissele has been fine, just pick what kind of trigger bow you want and how heavy. Larue mbt isn't bad for the price.

Bcm mod 3 grip. I have medium hands (or so my wife tells me) and the larue grips were too big

 

[Greg Langelius *]

I have two nearly identical Stag Model 6 Super Varminter Lowers and, now, seven Uppers.

I have found that the standard A2 buffer handles everything so far.

I have no purpose that would be served by a collapsible stock. The lowers have an A2 stock, and a Luth AR MBA-1. I need extra LOP and the Luth AR provides this admirably. The other Lower is nominally my Granddaughter's and the A2 stock accommodates her quite well.

The Stag Lowers come with the Stag two-stage trigger, and I like it quite a bit.

The Uppers, besides the identical pair of 24" heavy stainless barreled Model 6 Super Varminter Uppers, include three 16", and two 6.5 Grendel, a 20" and a 24", both heavyweight.

The only accessories I add are clone bipods, a Magpul B.A.D. Lever, and Caldwell adapters for their brass catcher; I tend to shoot handloads nearly exclusively. For F Class shooting, each Lower has a dedicated single feed follower/Bob Sled to permit single feeding as required by NRA/F Class rules.

Greg

 

[RyanScott]

The A2 is the length it is because the USMC rifle team liked it for shooting all slung up in traditional match offhand. A1 is a better length.

 

[jab00]

Good point aboit the slight LOP difference between the A1 and A2 because I would definitely like a slightly shorter length of pull overall.