Stripped Lowers

[Dave L.]

My newest build features a Sabre Defence stripped lower which is of excellent quality.

Where did you get it/how much?

[Mooneys]

My Bushamster lower looks like crap, compared to the Stag lower I just bought.

I agree...BM makes a decent lower but they need to take some additonal time and clean up the leftover flashing.

[govm4]

I am thinking of going with Superior Arms for my next build.

[shark31]

+1 for Denny's/GTS lower. You get Stag/CMT quality, plus all the extra attention to the small details like mag wells and forging marks means that more people get their hands on the lower. This leads me to believe that they have greater QC than most. The best part is it's a bargain.

[kel3at]

The only real difference between the major brands is that some fit better with certain upper recievers. I have a superior arms, which is a nice lower, but doesn't fit as tight to my CMT upper as my RRA lower fits to it. The RRA has no play at all. I heard that RRA lowers are made by CMT, so I'm assuming that a STAG lower would fit tight too, but I cant say for sure.

For my next build I will probably just buy an RRA lower to mate with a CMT upper.

[Bulldog1967]

I've only built on 1 lower so fat=r, but it was an Laurer/LMT which was EXCELLENT finish.

[tikkafan]

I got two Mega lowers from rainierarms.com, back when I think they cost $90.

I was amazed by the quality of the machining. The only AR-15 experience I had to that point was from the Army. Totally different level of quality.

Plus the atomic logo is really cool.

+1 on Mega and rainierarms.com

[mat10x]

is this info accurate? saw it from here..

http://www.calguns.net/calgunforum/a...p/t-50947.html

what does this mean..." The ribbed A2 strength on the reciever extension lug is thinner on the LMT, while the CMT is almost the full width."...?

still debating on LMT vs Noveske as i understand CMT makes noveskes upper/lower.

thx.

xenophobe
03-04-2007, 09:05 AM
Receiver FAQ Version 0.1 (please note this is still rough, and is not nearly finished)

I live in a ban state, so no luck getting Bushmaster, Armalite, DPMS or Colt into the mix. My apologies.

I see a lot of threads asking about Quality and Suggestions for which brand of receiver any particular person would buy, so I thought I might write this info I've posted in a number of places to have it's own thread.

There are currently FOUR manufacturers that produce the majority of lower receivers for the AR market. MMS, CMT, LMT and LAR receive orders from many licensed manufacturers who obtain an ATF variance to have them cut and logo receivers on their behalf. JVP and Superior Arms cut for a couple of different companies as well, but currently I will only focus on the four main manufacturers differences.

Mega, Stag (CMT), LAR and Barrett (LMT):
http://img148.imageshack.us/img148/7830/381.jpg


Not all inclusive, and a few brands have had more than one manufacturer cut their receivers. Many companies receive CMT and LMT cuts in the white and finish them themselves. I have not seen a LAR or MMS cut that was finished by a third party company.

LMT = LMT, Lauer(old), DS Arms, PWA, Eagle, Knights Armament, Barrett, Bushmaster (?)
CMT = Stag, RRA, High Standard, Noveske, Century (current), Global Tactical, CLE, S&W, MGI, Wilson Tactical, (some?) Colt, Ratworx
LAR = Grizzly, Bushmaster (L Prefix), Ameetech, (?)DPMS, CMMG, Double Star, Fulton
JVP = Double Star, LRB
MMS = Mega, GSE, Dalphon, POF (forged), Alexander Arms,
Olympic = Olypmic, SGW, Tromix, Palmetto, Dalphon, Frankford, (old) Century
Sun Devil = Sun Devil forged billet receivers
Superior = Superior Arms, Lauer (current)
Grenadier Precision

Characteristics of the manufacturers (please note, the most typical characteristics are listed, and each manufacturer may have substantial sample variation between lots):

LMT usually leaves forge flash underneath the trigger well, and roughly cuts them between the receiver extension and pistol grip, while leaving a vertical mold flash line on the front lip of the mag well, as well as having other "fingerprint" marks... no bevel cut for the charging handle on the rear lug for the receiver extension, as well as particular mill marks in between the pivot pin tangs. They also have a 'fingerprint' cut in the receiver on the shelf, and below it where the FCG goes. Notice the diagonal mill mark on one of the pivot pin supports. Also unique is the radius in the grip tang pocket, which is not as smooth a transition as the other manufacturers.

http://img148.imageshack.us/img148/5...8/842/lmt2.jpg
xenophobe
03-04-2007, 09:09 AM
CMT has a rounded bevel on the front of the mag well lip, generally removes the forge flash underneath the trigger well, usually offers a smooth and rounded surface between the receiver extension and pistol grip and has a unique mill mark that would be hidden by the attachment of a pistol grip. There is also a clamp mark of some sort that occurs on the top of the pivot pin lugs that LMT and LAR do not have (see 1st photo at beginning of thread).

http://img148.imageshack.us/img148/3.../6706/cmt3.jpg

LAR sometimes leaves forge flash underneath the trigger well, and does have a smooth flat milling mark on the round transition on the web between the receiver extension and grip. By the back of the grip tang, there is a milling mark that goes across the width of the receiver. The front of the receiver has a deep cut between the pivot pin retainers, and the front of the mag well is not always flat. The front radius to the mag well bevel is round, but the front edge sometimes shows forge flash.

http://img148.imageshack.us/img148/8.../7054/lar2.jpg
xenophobe
03-04-2007, 09:11 AM
MMS usually the cleanest cut, with the exception of some CMT receivers. All of the MMS receivers for Mega, POF, Gunsmoke, Dalphon and Stinger I've seen have the typical black teflon coating. Some of the receivers look absolutely perfect, others have mag wells that are cut from both sides and don't quite match up in the center. Some of them also have what look like file marks running in one direction on part of all of the receiver, and can be somewhat subdued or very noticable. I won't describe machining fingerprints, because all Mega manufactured receivers are pretty obviously made by MMS.

http://img148.imageshack.us/img148/4.../9693/mms2.jpg

The forgings that CMT and LMT use are also from different manufacturers. The ribbed A2 strength on the reciever extension lug is thinner on the LMT, while the CMT is almost the full width. Mega appears to use the same forgings as LMT. All of the manufacturers seem to have some variation of mag well bevels, and those aren't primarily useful in identification.

From left to right, Mega, Stag/CMT, LAR, LMT and Barrett,

http://img177.imageshack.us/img177/2847/73704265co7.jpg
xenophobe
03-04-2007, 09:12 AM
Other comparisons
All of the following photos will show from left to right; Mega, Stag, LAR, Barrett and/or LMT:

Notice the lack of a charging handle bevel on the Barrett/LMT
http://img177.imageshack.us/img177/4400/30755159bs4.jpg

Notice the difference between the LMT and the larger mag well bevel of the Barrett (far right):
http://img148.imageshack.us/img148/3703/382.jpg

Trigger well forge flash clearly visible on the Barrett and LMT:
http://img177.imageshack.us/img177/8997/57432685hm8.jpg

http://img148.imageshack.us/img148/842/384.jpg
xenophobe
03-04-2007, 09:16 AM
http://img177.imageshack.us/img177/5179/14018510eb5.jpg


Links to the manufacturers:
LMT = Lewis Machine and Tool
www.lewismachine.net (http://www.lewismachine.net)

CMT= Continental Machine and Tool
www.continentalmachinetool.com (http://www.continentalmachinetool.com)
www.stagarms.com (http://www.stagarms.com) (an individual corporation that was started by CMT)

LAR = some combination of the original owner's last initials
www.larmanufacturing.com (http://www.larmanufacturing.com)
www.largrizzly.com (http://www.largrizzly.com)

MMS=Mega Machine Shop
www.megamachineshop.com (http://www.megamachineshop.com) (new)

JVP=JV Precision
jvprecision.net (http://jvprecision.net)

Superior Arms
www.superiorarms.com (http://www.superiorarms.com)


Okay, I'm done for now... whew... More info and pics later.

If there are any corrections, or requests for pics/comparisons of angles I have not yet posted, please PM me.

[rifleshooter]

is this info accurate? saw it from here..

http://www.calguns.net/calgunforum/a...p/t-50947.html

what does this mean..." The ribbed A2 strength on the reciever extension lug is thinner on the LMT, while the CMT is almost the full width."...?

still debating on LMT vs Noveske as i understand CMT makes noveskes upper/lower.

thx.

xenophobe
03-04-2007, 09:05 AM
Receiver FAQ Version 0.1 (please note this is still rough, and is not nearly finished)

I live in a ban state, so no luck getting Bushmaster, Armalite, DPMS or Colt into the mix. My apologies.

I see a lot of threads asking about Quality and Suggestions for which brand of receiver any particular person would buy, so I thought I might write this info I've posted in a number of places to have it's own thread.

There are currently FOUR manufacturers that produce the majority of lower receivers for the AR market. MMS, CMT, LMT and LAR receive orders from many licensed manufacturers who obtain an ATF variance to have them cut and logo receivers on their behalf. JVP and Superior Arms cut for a couple of different companies as well, but currently I will only focus on the four main manufacturers differences.

Mega, Stag (CMT), LAR and Barrett (LMT):
http://img148.imageshack.us/img148/7830/381.jpg


Not all inclusive, and a few brands have had more than one manufacturer cut their receivers. Many companies receive CMT and LMT cuts in the white and finish them themselves. I have not seen a LAR or MMS cut that was finished by a third party company.

LMT = LMT, Lauer(old), DS Arms, PWA, Eagle, Knights Armament, Barrett, Bushmaster (?)
CMT = Stag, RRA, High Standard, Noveske, Century (current), Global Tactical, CLE, S&W, MGI, Wilson Tactical, (some?) Colt, Ratworx
LAR = Grizzly, Bushmaster (L Prefix), Ameetech, (?)DPMS, CMMG, Double Star, Fulton
JVP = Double Star, LRB
MMS = Mega, GSE, Dalphon, POF (forged), Alexander Arms,
Olympic = Olypmic, SGW, Tromix, Palmetto, Dalphon, Frankford, (old) Century
Sun Devil = Sun Devil forged billet receivers
Superior = Superior Arms, Lauer (current)
Grenadier Precision

Characteristics of the manufacturers (please note, the most typical characteristics are listed, and each manufacturer may have substantial sample variation between lots):

LMT usually leaves forge flash underneath the trigger well, and roughly cuts them between the receiver extension and pistol grip, while leaving a vertical mold flash line on the front lip of the mag well, as well as having other "fingerprint" marks... no bevel cut for the charging handle on the rear lug for the receiver extension, as well as particular mill marks in between the pivot pin tangs. They also have a 'fingerprint' cut in the receiver on the shelf, and below it where the FCG goes. Notice the diagonal mill mark on one of the pivot pin supports. Also unique is the radius in the grip tang pocket, which is not as smooth a transition as the other manufacturers.

http://img148.imageshack.us/img148/5...8/842/lmt2.jpg
xenophobe
03-04-2007, 09:09 AM
CMT has a rounded bevel on the front of the mag well lip, generally removes the forge flash underneath the trigger well, usually offers a smooth and rounded surface between the receiver extension and pistol grip and has a unique mill mark that would be hidden by the attachment of a pistol grip. There is also a clamp mark of some sort that occurs on the top of the pivot pin lugs that LMT and LAR do not have (see 1st photo at beginning of thread).

http://img148.imageshack.us/img148/3.../6706/cmt3.jpg

LAR sometimes leaves forge flash underneath the trigger well, and does have a smooth flat milling mark on the round transition on the web between the receiver extension and grip. By the back of the grip tang, there is a milling mark that goes across the width of the receiver. The front of the receiver has a deep cut between the pivot pin retainers, and the front of the mag well is not always flat. The front radius to the mag well bevel is round, but the front edge sometimes shows forge flash.

http://img148.imageshack.us/img148/8.../7054/lar2.jpg
xenophobe
03-04-2007, 09:11 AM
MMS usually the cleanest cut, with the exception of some CMT receivers. All of the MMS receivers for Mega, POF, Gunsmoke, Dalphon and Stinger I've seen have the typical black teflon coating. Some of the receivers look absolutely perfect, others have mag wells that are cut from both sides and don't quite match up in the center. Some of them also have what look like file marks running in one direction on part of all of the receiver, and can be somewhat subdued or very noticable. I won't describe machining fingerprints, because all Mega manufactured receivers are pretty obviously made by MMS.

http://img148.imageshack.us/img148/4.../9693/mms2.jpg

The forgings that CMT and LMT use are also from different manufacturers. The ribbed A2 strength on the reciever extension lug is thinner on the LMT, while the CMT is almost the full width. Mega appears to use the same forgings as LMT. All of the manufacturers seem to have some variation of mag well bevels, and those aren't primarily useful in identification.

From left to right, Mega, Stag/CMT, LAR, LMT and Barrett,

http://img177.imageshack.us/img177/2847/73704265co7.jpg
xenophobe
03-04-2007, 09:12 AM
Other comparisons
All of the following photos will show from left to right; Mega, Stag, LAR, Barrett and/or LMT:

Notice the lack of a charging handle bevel on the Barrett/LMT
http://img177.imageshack.us/img177/4400/30755159bs4.jpg

Notice the difference between the LMT and the larger mag well bevel of the Barrett (far right):
http://img148.imageshack.us/img148/3703/382.jpg

Trigger well forge flash clearly visible on the Barrett and LMT:
http://img177.imageshack.us/img177/8997/57432685hm8.jpg

http://img148.imageshack.us/img148/842/384.jpg
xenophobe
03-04-2007, 09:16 AM
http://img177.imageshack.us/img177/5179/14018510eb5.jpg


Links to the manufacturers:
LMT = Lewis Machine and Tool
www.lewismachine.net (http://www.lewismachine.net)

CMT= Continental Machine and Tool
www.continentalmachinetool.com (http://www.continentalmachinetool.com)
www.stagarms.com (http://www.stagarms.com) (an individual corporation that was started by CMT)

LAR = some combination of the original owner's last initials
www.larmanufacturing.com (http://www.larmanufacturing.com)
www.largrizzly.com (http://www.largrizzly.com)

MMS=Mega Machine Shop
www.megamachineshop.com (http://www.megamachineshop.com) (new)

JVP=JV Precision
jvprecision.net (http://jvprecision.net)

Superior Arms
www.superiorarms.com (http://www.superiorarms.com)


Okay, I'm done for now... whew... More info and pics later.

If there are any corrections, or requests for pics/comparisons of angles I have not yet posted, please PM me.

Well it sure does give one a few things to look at. Sure nothing wrong with looking at details.
Now if the DEVIL is really in the details I guess one should plot out each detail of every lower then make their mind up as to what details or one major detail really make one lower stronger "better" then the others.

Maybe others can chime in on the make of lowers they have seen or read of having failures in their forgings.

Anyway I don't think I will lay awake tonight worring about the forging on my LM&T AR.

[mat10x]

new to ARs, so the more i read, the more questions i have. getting bogged down in the details.

was just wondering if there is any big difference between CMT and LMT products other than the level of finish. is one more durable than the other...? same specs, different roll marks? i read that noveske has his uppers/lowers made to his specs...but how different is that from LMT?

i understand noveske spends more time on the fit/finish of their uppers/lowers and LMT just makes them work.

looking at a N4 basic recce 16" or a LMT standard 16". thinking of a middy, LMT middy only comes in MRP.