LMT .308 MWS

TacosGigante

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I think he turns the shank to a straight contour if needed, installs a sleeve over it, machines to correct dimensions and takes off the index pin. Just like the mrp conversions. I have a 18” 5.56 and 24” 6.5 creedmoor that Marvin did for me. Excellent work.
Do I send in the bolt that comes with the barrel or is part of the work getting the barrel to work with a standard LMT bolt?
 

newguy2k3v2

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I would love to hear more how a collar that determines where the barrel sits has no effect on headspace.
I'd like to hear how the sleeve that allows the barrel to be clamped into the upper changes the fit between the extension and the bolt?

Does the bolt headspace on the upper or the barrel extension, which isn't touched other than removing the index pin?
 

blbennett1288

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    I'd like to hear how the sleeve that allows the barrel to be clamped into the upper changes the fit between the extension and the bolt?

    Does the bolt headspace on the upper or the barrel extension, which isn't touched other than removing the index pin?
    There is no “clamping” of the barrel to the upper horizontally. The barrel/extension/collar is all a single unit. The machining of your collar and the index pins is going to determine where the the extension is located; which in turn determines headspace.
     

    newguy2k3v2

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    There is no “clamping” of the barrel to the upper horizontally. The barrel/extension/collar is all a single unit. The machining of your collar and the index pins is going to determine where the the extension is located; which in turn determines headspace.
    On a factory barrel yes. On a converted barrel the standard extension remains and the sleeve is added to the barrel
     

    Skunkworx

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    I would love to hear more how a collar that determines where the barrel sits has no effect on headspace.
    The sleeve mod doesn’t touch the part of the barrel that determines headspace. It only adds a clamping surface to the front of the barrel extension. The barrel still seats down to and indexes off the barrel extension shoulder like it always has.
     

    blbennett1288

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    The sleeve mod doesn’t touch the part of the barrel that determines headspace. It only adds a clamping surface to the front of the barrel extension. The barrel still seats down to and indexes off the barrel extension shoulder like it always has.
    If your holes on the collar are further away from the bolt, your barrel extension moves further away from the bolt also. So yes, your headspace will be effected, because the collar and hole index off the barrel extension
     
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    Skunkworx

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    If your holes on the collar are further away from the bolt, your barrel extension moves further away from the bolt also. So yes, your headspace will be effected, because the collar and hole index off the barrel extension
    Thank god the cross bolt hole has clearance.
     

    Jsp556

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    The bolt locks in the barrel extension no matter where the barrel extension is. Turn the extension down 0.005 so it seats deeper in the upper or shim it 0.005 further out, the bolt still locks in the extension. Headspace is set from the bolt face.
     

    blbennett1288

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    The bolt locks in the barrel extension no matter where the barrel extension is. Turn the extension down 0.005 so it seats deeper in the upper or shim it 0.005 further out, the bolt still locks in the extension. Headspace is set from the bolt face.
    Learn something new everyday. This is the concept I was missing. I was wrong @Skunkworx @newguy2k3v2
     
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    Kremvh

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    For those of y'all with 13.5" .308 barrels, what role are you using this gun? And what optic? I love mine, just have no idea what to do with it really.

    I've tried several LPVOs and scopes. Seems like the shorty .308 would be a good thermal host, but I haven't tried that yet. I use 5.56 SBRs for NV pig smashing with a T2 and PEQ.
     

    GUNNER10

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    Since I shoot on the east coast and there are no a lot of long sight lines, so I sort of use it as a CSASS type rifle similar to the KAC APC. With that being said, if I slap RDS on it I can do blaster stuff. Really, it can pretty much do anything I want it to inside of 800.

    Edited to add, The LPVO is fine, but I am going to shift that over to the ACC and the Eotech to a 556.

    Heavier accuracy type stuff


    Blaster type stuff
     
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    aslrookie

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    Since I shoot on the east coast and there are no a lot of long sight lines, so I sort of use it as a CSASS type rifle similar to the KAC APC. With that being said, if I slap RDS on it I can do blaster stuff. Really, it can pretty much do anything I want it to inside of 800.

    Edited to add, The LPVO is fine, but I am going to shift that over to the ACC and the Eotech to a 556.

    Heavier accuracy type stuff


    Blaster type stuff
    Is that the 13.5” 7.62 barrel? Hows the noise level suppressed? I’m considering this route.
     

    GUNNER10

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    Is that the 13.5” 7.62 barrel? Hows the noise level suppressed? I’m considering this route.
    It is,

    With that can, its fine, with cheap foam earplugs. Since its a lower pressure can, there is less noise at the shooters ear and more noise at the muzzle. Without the can, its quite concussive.

    I really like it.
     

    Kremvh

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    Is that the 13.5” 7.62 barrel? Hows the noise level suppressed? I’m considering this route.

    It is,

    With that can, its fine, with cheap foam earplugs. Since its a lower pressure can, there is less noise at the shooters ear and more noise at the muzzle. Without the can, its quite concussive.

    I really like it.
    I second this. I have a Surefire 7.62 Mini on my 13.5”. It’s brutal without a can and very pleasant with a can.
     

    aslrookie

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    Did you guys SBR them or just pin a long enough flashider/suppressor capable muzzle device? I already have SBRs, but I don’t want more unless absolutely necessary. Just makes going to other states on a short notice a lot easier.
     

    Kremvh

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    Did you guys SBR them or just pin a long enough flashider/suppressor capable muzzle device? I already have SBRs, but I don’t want more unless absolutely necessary. Just makes going to other states on a short notice a lot easier.
    I SBRd mine. But I live in Texas and rarely take a gun out of state.
     

    GUNNER10

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    Nice!! I’m having a 14.5” bartlein spun up with a pin/weld for mine. Going to be running the sandman-s… is that the K on yours?
    Nice.

    I really want to get a krieger or bartlien spun up one of these days, great barrels, it's the K. When I get back into the states I want to try the E Brake on it. I have no issues what so ever with it but just heard good things about it.

    I actually would like to toss it on one of my 556's and see how it sounds
     

    HenryTheAce

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    Nice.

    I really want to get a krieger or bartlien spun up one of these days, great barrels, it's the K. When I get back into the states I want to try the E Brake on it. I have no issues what so ever with it but just heard good things about it.

    I actually would like to toss it on one of my 556's and see how it sounds
    Yes they are! That K looks good on there. Agreed though, those E Brakes seem interesting, people seem to like em.
     

    bikejunky

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    Gunner10’s 13.5 inspired me to have one cut down and pin&weld my OSS flash hider. I really like the balance now. I just need to figure out my optic now…. the vortex is just a temporary option

    DCB551B5-BDB6-4AF5-B83D-F33689297C45.jpeg
     

    HenryTheAce

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    Gunner10’s 13.5 inspired me to have one cut down and pin&weld my OSS flash hider. I really like the balance now. I just need to figure out my optic now…. the vortex is just a temporary option

    View attachment 7680009
    Downright sexy man! I went with a Mark 5 for mine. CST has it right now, they’re cerakoating it fde along with spuhr. If I could afford to have a 3rd TT or another ZCO I would’ve 😂
     
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    jwramp

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    Threw a few 6.5 rounds over the chrono this morning in advance of next week's Border War match in PA. It's a 20" Douglas we ordered as a super huge blank, turned down and cut the cross pin slot in. So far so good after going from about 10.5 to 4lb of steel in the barrel. Looking forward to giving the gas gun division a try after taking quite a while off from competing.

    2021Aug-JWRRangePics-015.jpg
     

    Thorbeast

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    I was just thinking about putting a 419 rail on my MWS. Would it be possible to pull barrels without removing the rail? I'm guessing not... But I've also heard people say that if you grind the screws down, it's not a problem. How is it shooting off hand with that 419 rail on the gun?
     

    GUNNER10

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    Depending on how often your are actually pulling your barrel, It may not even be worth your time to trim the screws. i had mind trim pretty short on my panels, and I still need to take the panels off to remove the barrel. It would be nice if that was not the case, but in no way is it a show stopper.

    As for how is off hand with an acra rail, I imagine the same as shooting any other rifle offhand with a flat base like an AI/McM A4.
     
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    CeeTee556

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    I installed a 419 rail on my MWS a few days ago and I'm having second thoughts now... It seems a lot of weight is given to keeping your barrel at or below the apex of the "bipod triangle" for maximum stability and the added height of the rail and ARCALOCK clamp isn't helping those angles. Currently have the BT-46 mounted which is very narrow at the top. Already ordered a BT-65 which should help a bit but still on the fence about this whole arrangement.

    On a side note, anyone ordering a 419 rail for their MWS should request they send you the MLOK screws that have a smaller head which fit into the slot and holes in the rail without obstructing the movement of the ARCALOCK clamp. Standard Magpul MLOK screws won't work. Area 419 was nice enough to send me a set free of charge when I ran into this problem, great customer service.
     
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    newguy2k3v2

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    I gave my og billet mws a facelift and bought the 15.5" upper, then splurged again and picked up a mars dmr lower. I picked up the 12" area 419 ARCA lock rail and a CAL. I had to grind and shape the back of the ARCA rail to fit the upper and a slight chamfer at the front for the qd socket bump.

    I think I'm going to like it.
     

    blbennett1288

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    I gave my og billet mws a facelift and bought the 15.5" upper, then splurged again and picked up a mars dmr lower. I picked up the 12" area 419 ARCA lock rail and a CAL. I had to grind and shape the back of the ARCA rail to fit the upper and a slight chamfer at the front for the qd socket bump.

    I think I'm going to like it.
    Got any pics?
     

    CeeTee556

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    So stoked for this, D Wilson has done three conversions for me, two in 5.56 and one 9mm. He does great work.
     

    Lurp06x

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    Anyone thinking about putting one of the new Vortex Razor HD LHT on their MWS?
    Nope

    currently pondering the 1-8/10x market. I have a 3-15x NXS currently and like it a lot but I want something with a smaller profile.
     

    Bazooka

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    Nope

    currently pondering the 1-8/10x market. I have a 3-15x NXS currently and like it a lot but I want something with a smaller profile.
    I have the 1-10 Vortex on my LMT LRP-L. It's a nice optic. But, only .2 oz more and 3.2"in length for a 4.5-22x has peaked my interest.
     

    KM375

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    I have a MK 8 1-8 on a 16 inch and it does pretty well to 800, Ive been looking at getting a Vortex 1-10 for that platform a little more power for my aging eyes.
     

    blbennett1288

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    LMT MWS Defenders in stock at Primary Arms. No affiliation, just passing information along.

     
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    AnotherSandman

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    I figured it makes the most sense to put this here, but if not then let me know/mods move it.

    I have a stock LMT MWS and am finally moving to a state which allows me to buy a suppressor, so I'm trying to figure out what to get. I've been doing a bit of research and think I have it narrowed down to either an OSS HX QD 762 or Dead Air Nomad L. This will be a bench gun so weight and length aren't major concerns, but sound suppression is and being an MWS back pressure is as well.

    I'm considering the QD762 because of its fantastic reputation for low back pressure; apparently to the point that I wouldn't even need to swap in any parts such as heavier buffers. On the other hand, I've heard that their sound suppression is sub par. The Nomad L stands out to me as providing pretty darn good sound suppression without the cost of too much back pressure. Problem is that I don't know how much back pressure there is, and while I'm willing to tweak the recoil system, at this time I'm not willing to install an adjustable gas block or similarly modify the gas system.

    Can anyone provide any further insight into the above? I.e. how well the QD762 suppresses sound, how much back pressure the Nomad L produces, any ideas on mitigating back pressure in an MWS, and/or if the difference in sound suppression between these two options is splitting hairs.

    Another suppressor that caught my eye is the CGS Hyperion (full size, not k), but I haven't been able to find much data on its back pressure. If anyone can help out there, and/or recommend other suppressors I'd appreciate it.
     

    GUNNER10

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    I figured it makes the most sense to put this here, but if not then let me know/mods move it.

    I have a stock LMT MWS and am finally moving to a state which allows me to buy a suppressor, so I'm trying to figure out what to get. I've been doing a bit of research and think I have it narrowed down to either an OSS HX QD 762 or Dead Air Nomad L. This will be a bench gun so weight and length aren't major concerns, but sound suppression is and being an MWS back pressure is as well.

    I'm considering the QD762 because of its fantastic reputation for low back pressure; apparently to the point that I wouldn't even need to swap in any parts such as heavier buffers. On the other hand, I've heard that their sound suppression is sub par. The Nomad L stands out to me as providing pretty darn good sound suppression without the cost of too much back pressure. Problem is that I don't know how much back pressure there is, and while I'm willing to tweak the recoil system, at this time I'm not willing to install an adjustable gas block or similarly modify the gas system.

    Can anyone provide any further insight into the above? I.e. how well the QD762 suppresses sound, how much back pressure the Nomad L produces, any ideas on mitigating back pressure in an MWS, and/or if the difference in sound suppression between these two options is splitting hairs.

    Another suppressor that caught my eye is the CGS Hyperion (full size, not k), but I haven't been able to find much data on its back pressure. If anyone can help out there, and/or recommend other suppressors I'd appreciate it.

    I have a sandman k that's great on my mws, but you should really reach out to DA. They have large social media presence and this is something that they would be best situated to answer.
     

    blbennett1288

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    I figured it makes the most sense to put this here, but if not then let me know/mods move it.

    I have a stock LMT MWS and am finally moving to a state which allows me to buy a suppressor, so I'm trying to figure out what to get. I've been doing a bit of research and think I have it narrowed down to either an OSS HX QD 762 or Dead Air Nomad L. This will be a bench gun so weight and length aren't major concerns, but sound suppression is and being an MWS back pressure is as well.

    I'm considering the QD762 because of its fantastic reputation for low back pressure; apparently to the point that I wouldn't even need to swap in any parts such as heavier buffers. On the other hand, I've heard that their sound suppression is sub par. The Nomad L stands out to me as providing pretty darn good sound suppression without the cost of too much back pressure. Problem is that I don't know how much back pressure there is, and while I'm willing to tweak the recoil system, at this time I'm not willing to install an adjustable gas block or similarly modify the gas system.

    Can anyone provide any further insight into the above? I.e. how well the QD762 suppresses sound, how much back pressure the Nomad L produces, any ideas on mitigating back pressure in an MWS, and/or if the difference in sound suppression between these two options is splitting hairs.

    Another suppressor that caught my eye is the CGS Hyperion (full size, not k), but I haven't been able to find much data on its back pressure. If anyone can help out there, and/or recommend other suppressors I'd appreciate it.
    I don’t have hands on experience with the OSS, nor do I own a Sandman, but this is my humble opinion of someone who is currently in the same situation as you and has been testing and researching.

    Backpressure and suppression seem to share an inverse relationship. If it suppresses well chances are it’s higher backpressure. If it’s low backpressure chances are it’s louder than the competition. The suppression levels are all relative because it’s only a couple dB usually. There are some exclusions to this and we will get to that eventually.

    There are 2 ways to moderate gas:
    1.) Buffer weights
    2.) Gas Moderation

    Gas moderation can be achieved with an adjustable gas block, smaller gas tube, or adjustable gas key.

    Having shot the LMT with everything from XH to H2 and factory gas tube to 100% suppressed gas tube I can say that for me, with my cans, there is no combination that I find acceptable in a mid length system, granted it runs fine and is up to the intended accuracy standards.

    I personally believe that running a LMT MWS suppressed requires an AGB. I am on this step of the process and waiting for a barrel from Lothar Walther with a rifle length gas system.

    If I was starting out and looking at suppressors I would pick something that manufactures recommend on their large frame gas guns. FN developed theirs around Surefire. HK recommends OSS and they don’t have an adjustable gas system on the MR762. The sandman K I shot on my MWS was better than any of my cans.

    Exception is over bored cans, so anything greater than 30cal. I have run a 338 ultra and SiCo hybrid and it certainly brings the gas levels down compared to a 30cal can.

    I hope this helps you in your search for a can for the MWS
     

    GUNNER10

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    I don’t have hands on experience with the OSS, nor do I own a Sandman, but this is my humble opinion of someone who is currently in the same situation as you and has been testing and researching.

    Backpressure and suppression seem to share an inverse relationship. If it suppresses well chances are it’s higher backpressure. If it’s low backpressure chances are it’s louder than the competition. The suppression levels are all relative because it’s only a couple dB usually. There are some exclusions to this and we will get to that eventually.

    There are 2 ways to moderate gas:
    1.) Buffer weights
    2.) Gas Moderation

    Gas moderation can be achieved with an adjustable gas block, smaller gas tube, or adjustable gas key.

    Having shot the LMT with everything from XH to H2 and factory gas tube to 100% suppressed gas tube I can say that for me, with my cans, there is no combination that I find acceptable in a mid length system, granted it runs fine and is up to the intended accuracy standards.

    I personally believe that running a LMT MWS suppressed requires an AGB. I am on this step of the process and waiting for a barrel from Lothar Walther with a rifle length gas system.

    If I was starting out and looking at suppressors I would pick something that manufactures recommend on their large frame gas guns. FN developed theirs around Surefire. HK recommends OSS and they don’t have an adjustable gas system on the MR762. The sandman K I shot on my MWS was better than any of my cans.

    Exception is over bored cans, so anything greater than 30cal. I have run a 338 ultra and SiCo hybrid and it certainly brings the gas levels down compared to a 30cal can.

    I hope this helps you in your search for a can for the MWS

    Good Advice, the only thing that I would add in regards the relationship between back pressure and suppression. Lower back pressure cans are generally louder at the muzzle BUT quite at the ear than a typical higher back pressure can that was built to suppress as much as possible.

    The question that one has to ask themselves is it more important to have the gun quieter at the muzzle or at the shooters ear? I personally don't know what the practical difference is between a can the meters 142 vs 148, 400 or 500 yards down range? My gut says that that difference is going to be negligible, so that is sort of why I really like Low pressure cans on gas guns.

    I think higher back pressure/full size cans make much more sense on bolt guns or gas guns set up to shoot subs.
     

    Vivacious Stallion

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    I figured it makes the most sense to put this here, but if not then let me know/mods move it.

    I have a stock LMT MWS and am finally moving to a state which allows me to buy a suppressor, so I'm trying to figure out what to get. I've been doing a bit of research and think I have it narrowed down to either an OSS HX QD 762 or Dead Air Nomad L. This will be a bench gun so weight and length aren't major concerns, but sound suppression is and being an MWS back pressure is as well.

    I'm considering the QD762 because of its fantastic reputation for low back pressure; apparently to the point that I wouldn't even need to swap in any parts such as heavier buffers. On the other hand, I've heard that their sound suppression is sub par. The Nomad L stands out to me as providing pretty darn good sound suppression without the cost of too much back pressure. Problem is that I don't know how much back pressure there is, and while I'm willing to tweak the recoil system, at this time I'm not willing to install an adjustable gas block or similarly modify the gas system.

    Can anyone provide any further insight into the above? I.e. how well the QD762 suppresses sound, how much back pressure the Nomad L produces, any ideas on mitigating back pressure in an MWS, and/or if the difference in sound suppression between these two options is splitting hairs.

    Another suppressor that caught my eye is the CGS Hyperion (full size, not k), but I haven't been able to find much data on its back pressure. If anyone can help out there, and/or recommend other suppressors I'd appreciate it.
    I run a SICO Hybrid on my 16" and 13.5" barrels (as well as shot it with my sandman s that's in jail once). The recoil with the hybrid on the stock gun was "violent". I put the XH (8.5oz) buffer in and it makes the gun acceptable suppressed with low back pressure cans. I know some people say the surefire cans are better with the stock gun. Maybe they are a little, but my friend who has that setup is now changing to the XH buffer after he borrowed mine. In my opinion, running the XH buffer is an improvement shooting with or without a can with no change to reliability.

    I also have the unsuppressed BRT gas tube as well and that combination seems to be the closest happy medium for my setup. However, as others above have said above, the best suppression cans tend to have some of the highest backpressure. The Nomad is a good can but its definitely higher BP than a overbored can, sandman, or surefire. If you go that route you'll probably be better off going straight to a true adj. gas block and not messing with the tubes.