Okay, I have my upper coming

[Traxx]

Is there anything special that I will need for the lower? Or will a standard 5.56 lower work?

[txgunner00]

Standard receivers are good to go.

What part of TX are you in?

[Costa]

Just need to make sure you have grendel mags.

[Traxx]

There is one mag coming with the upper and 2 others on order along with the T-shirt. I am in Ft Worth and soon to be in Dawson.

[jwilson1985]

be careful one what lower you choose, not all are up to spec

[Traxx]

cmmg or spikes

[jwilson1985]

out of the two cmmg..im not going to bash the other if u wanna know pm me alot of ppl love them. but i doubt they have shot much or can tell the differience in the messurements or the weapon

[LRRPF52]

Consider getting a heavier buffer, if you don't have one already. I only shoot the Grendel with about a 4oz ST-T2 with tungsten powder in it. H3 is usually a good buffer for the Grendel's increased gas impulse. I would go to the range with 2 of them, an H2 and an H3...unless you are using a standard rifle-length extension tube/stock, which has a 5.2oz buffer.

Lowers are lowers nowadays, unless you want something special like billet, flared mag wells, etc. All of your forged lowers are made by a handful of machine shops in the US, then sent out to all the assemblers, who have the big name recognition. The biggest companies get theirs from the same machine shop here in the Salt Lake Valley...like 85% of the market, just run with different engravings and serial numbered lots per manufacturer's specs and ATF logs.

[jwilson1985]

all loweres r not created the same thos lr is rit three are only a handfull of people making them but next gun shop you go into that your in good with take i micrometer to them see how many are different

[leopard6.5]

LRRPF52: Which buffer weight would you reccomend for a lower that will be used to switch between a 5.56/.223 upper and a 6.5 Grendel upper?

Would you reccomend using the Spikes ST-T2 or the Spikes H3?

The lower has an adjustable buttstock on it with a carbine buffer in it.

Thanks.

Lee

[LRRPF52]

I would take as many buffers as you have to the range with you. If you want a common buffer between both calibers, it will depend on your 5.56 gas system and dwell-time set-up as well. A 16" barrel with a carbine-length gas system is probably one of the hardest on the action, and will run better with an M16 carrier first, then whatever buffer weight balances out the system with the ammo you use, and the gas port diameter that it has. A smaller gas port will provide a milder impulse, while a larger will be more voluminous per time, and usually sharper in the same set-up. A 16" mid-length or even rifle-length gas system is easier on the system, since the gas port pressure is lower. What type of 5.56 upper do you have?

[pinzgauer]

After building other lowers I started realizing that if using known mfg mil-spec parts I was not saving much compared to the cost of an LMT complete lower. Unlike some of the fad mfg's out there, LMT just focus's on building mil-spec equipment per the TDP. Daniel Defense would be my other choice but they do not sell standalone uppers right now.

If you are wanting high end triggers, etc it may still make sense to build. But a solid M4 lower, LMT is the best route in my view.

I did swap in an H2 buffer and magpul CTR stock.

If you feel compelled to build one, the current hot deals are the Aero Precision stripped lowers private labeled. I've been seeing them as cheap as $65 shipped, or $80 in local stores.

Add a DD LPK as well as milspec buffer tube & Magpul MOE stock and you are set. DSG has them all and will let you specify your buffer weight.

There are some items that places like Palmetto State Armory can save you money on, but when you can get a Daniel Defense LPK for the same price as generics it's not worth saving.

I'm not a Spikes fan as they have only recently started meeting mil-spec on many of their items. And even some of that is in question. Just not worth paying a premium.

[YutYut]

http://www.karrisguns.com/
the loweres will go on sale for 5 bucks cheaper every now and then

[pinzgauer]

Yes, these are the Aero Precision lowers, very well made and when this cheap no reason to take a blem from someone else.

When you stack a transfer fee on them it will often make sense just to buy local when you can. I've seen them $80 at local stores & shows.

http://www.karrisguns.com/ar-15-lower-re...ctor-marks

[leopard6.5]

LRRPF52: The first lower is a pre-ban Colt AR-15 lower and won't accept a M16 carrier because of this tab( says Colt on the top) that sticks up where the channel on the M16 carrier is. That was my first thing to try to add weight. The barrel is a 16" with the gas port drilled at 11"( is that carbine or mid-length?). It's a generic upper that I built.

The second lower is a POF with a POF piston upper with a 16" barrel and the gas port drilled at 11" also. This has a M16 carrier with a carbine buffer.

Both these lowers will be used to switch between the 5.56/2.23 and AA Grendel uppers( 18" with mid-length gas system).

I would prefer to be able to use one buffer if possible so I don't have to worry about switching all the time and I want to try to keep the system from beating itself up as much as possible.

Hopefully this gives you a little more info to base your recommendation on.

Thanks again.

Lee

[LRRPF52]

I would try either the Spike's ST-T2 or the ST-T3. I have used my ST-T2 with Grendel and 5.56 in mid and carbine-length gas systems, all with 16" barrels, and have had zero reliability issues in either.

I'm not sure where you're measuring your gas system lengths from, but a Carbine-Length Gas System (CLGS) is 7" from the receiver extension face to the gas port drilled in the barrel, a Mid-Length gas System (MLGS) is 9", and a Rifle-Length Gas System (RGLS) is 12.5". The upper receiver extension face is where the threads for your barrel nut are. You have to look at an upper with the barrel pulled to see them.

Right now, I think the best deal on lowers is from Templar, and I would have ordered two from them for $55 or $65 before ordering the two from PSA for $49.95, although the anodizing on the two PSA lowers I received is better than most I have seen in the industry in a long time. The Templar lowers have a generously and well-executed funneled mag well, and a captivated take-down pin detent channel. They are basically a $175 lower for $65, in my opinion.

I've dealt with or owned lowers from PWA, Bushmaster, RRA, DPMS, Olympic Arms, DSA, Armalite, Colt, CMMG, American Spirit Arms, Fulton, POF, Essential Arms, Eagele Arms, JP, LMT, Spike's Tactical, High Standard, Noveske, Century, S&W, MGI, Wilson, Double Star, Mega, Sun Devil, Superior Arms, Aero Precision, NoDak, McKay, and a bunch of custom-made versions to boot. All those lowers I just mentioned are made by only 9 different machine shops around the country, and LAR makes the highest volume of them for the big names like Bushmaster, DPMS, CMMG, Double Star, Spike's, and others.

I personally don't care what name is on my lower, but price first, fit with uppers second (this is a trial-and-error game, unless you buy a custom-matched set), and anodizing third. Then I look at differentiation in features, which is usually only funneled mag wells in your basic forged lowers. Whatever you do, don't pay for a standard forged lower based on what name is engraved on it, as that is pretty meaningless nowadays. There are minor tolerance differences in mass-produced parts, but I just don't see many functional problems like I occasionally used to in the early 90's.