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LMT MWS Upper compatibility

Mumbles

Sergeant
Full Member
Minuteman
Feb 21, 2008
355
7
Pittsburgh Area
Looking for information on what upper receivers and parts are compatible with an MWS lower. I believe you can drop a KAC upper on an LMT lower with zero issues, but I don't know that KAC sells just the upper, and if they did it would probably cost enough that it wouldn't be worth it over just getting an entire SR-25.

I'd like to put together a lightweight upper for my MWS on the cheap (or at least cheaper than a new SR-25 ECC or PredatAR). Is there anyone that sells the parts necessary to accomplish this? I know it can be done fairly easily with DPMS pattern rifles, but what's the deal with KAC/LMT/Larue pattern?

Anyone know anything about the compatibility of a current production factory AR-10A upper?
 
I would only bet on LMT/KAC compatibility. Larue and others have some slightly different things that could possibly cause you trouble. That said; I do know JP bolts and carriers are good to go in LMT as well.

FWIW; the larue 308 mags I bought will NOT fit my LMTLM8MWS, REPR or GAP10. I have tried them in another shooter's LMT and REPR as well, no love.
 
I have been looking for a mws upper for one of my sr25's so if there is any chance you are selling one or know someone that is you have a very serious buyer here. I did have a lead on a early 16" kac upper from a guy a while ago. It was one from around the sr25k era but it wasn't off one. It was from a special run they did for an editor to test in th 90's. It was from a one off gun that had three uppers, one was this 16". I think he wanted around 2500. If you are interested contact me and I will try and dig up his info to see if he still has it. He may have had bigger uppers, if I could get one would you trade an mws for a heavier kac? Let me know and I can check into it. Thanks, Steven
 
Sorry, definitely not interested in parting with my MWS upper. I was just hoping to find info on a way to put together a lightweight upper to use on the same receiver for less than the price of an entire rifle from KAC.

I don't have $2500 lying around right now, but I appreciate the help.
 
Not a prefect fit with out machining for the mega , but AR-10A (A Model) uppers are a go so are B model uppers that have been machined out to fit the mags.


Anybody know anything about Mega Arms compatability?
 
Revisiting this, a few questions and clarifications:

-I have confirmed what Kult said about AR-10A uppers being a go. Unfortunately, I don't seem to be able to come up with an AR-10A upper (or rifle). If anyone has one, I'm interested.

-How much machining would be necessary to fit a Mega Upper? Anyone have any pictures of a Mega upper on a KAC/LMT/Larue/Armalite lower? Specifically close ups of problem areas.

-Anyone know of a source of stripped uppers that will fit an LMT lower? All I've been able to come up with is KAC paired upper/lowers stripped that cost as much as an entire Armalite rifle, and Mega stripped uppers, which apparently aren't a match.
 
I talked with a guy from LMT and he was telling me they are currently working on a price list of all the parts that make a MWS including uppers. So in the next few weeks-months you should have the ability to simply purchase a second upper. They will NOT be selling lowers.
 
I talked with a guy from LMT and he was telling me they are currently working on a price list of all the parts that make a MWS including uppers. So in the next few weeks-months you should have the ability to simply purchase a second upper. They will NOT be selling lowers.

I don't think the OP is looking for another MWS upper. I think he is trying to build a lightweight upper for his current MWS lower. If he's looking for another MWS upper, I have a spare one for sale.
 
I don't think the OP is looking for another MWS upper. I think he is trying to build a lightweight upper for his current MWS lower. If he's looking for another MWS upper, I have a spare one for sale.

Right on. I missed that. How much do you want for your spare upper? Is it a slick side?
 
The MWS lower will fit with an SR25 upper but it was slightly off from an OBR upper the rear take down pin wouldn't go.
 
Do you happen to know what the stock rear pin diameter is on an OBR. .278 or .282

The MWS lower will fit with an SR25 upper but it was slightly off from an OBR upper the rear take down pin wouldn't go.
 
I'll ask my friend to measure the pin. He also has 2-SR25's which had the same problem. Rear was a little off and rear take down pin wouldn't go.

Do you happen to know what the stock rear pin diameter is on an OBR. .278 or .282
 
Well if the SR is pre MK11 the lower might be the issue.

I'll ask my friend to measure the pin. He also has 2-SR25's which had the same problem. Rear was a little off and rear take down pin wouldn't go.