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  • Soft mount design

    Hi there. I’m new to this forum and I have a few questions I’m hoping some of you might be able to help me out with.

    I’m a mechanical engineering student and my final master thesis is to improve the Vinghoeg soft mount for M2 .50 cal HMG and MK 19 / HK GMG 40mm AGLs. This mount is standard in many NATO countries. I’m not sure whether “my” mount is used by the US, but another Vinghoeg mount is standard in the Stryker’s weapon station, and if I come up with something good the Stryker will probably benefit from it too.

    Here are a couple of links:

    http://www.vinghog.com/N_Products/Mo...tmount_127.htm

    http://www.vinghog.com/N_Products/We...nStations.html

    I figure this might be a place to find people with user experience, so here’s a couple of questions for any who might be interested:

    1 – General input on how HMGs and 40mm AGLs are used in practice. How long bursts, ammo load etc. And another thing: The Stryker's weapon station is fitted with laser range finder, up to 30x zoom and all kinds of goodies, but from what I’ve seen they seem to be used quite a lot in the good old “fire a few bursts and adjust when you see where the bullets land” style.

    2 – Experiences/feedback/thoughts on any soft mount systems you’re familiar with: Conditions where they fail, drawbacks, maintenance considerations, accuracy in single and auto fire, ergonomics and generally what you think of them. Are there any features you have missed?

    3 - Most mounts for the M2 use just the spade grips as user interface (no shoulder bar as in the Vinghoeg mount). It seems to me that must make the weapon bounce around a lot while firing. Is it possible to use the sights while firing automatic that way?

    4 - In my limited experience the M2 has jammed a lot. Possibly as much as once or twice every 100 rounds. I've never used the Mk 19 or HK GMG. Anyone else who has better experiences?

    5 – The M 240 / MAG 58 has 3 different rate of fire settings. Which setting is used when? Or are the two higher settings just for when the weapon is dirty?

    Actually, any kind of info regarding the damping and sliding mechanisms in weapons and mounts would be appreciated. Lots of weapons, the M2 .50 cal among them, operate with a sliding barrel: Anybody out there who’s taken the M2 apart a lot who could give me a hint to how the barrel’s locked to the weapon without parallax dispersion? (may be a bit too optimistic here :-)

    OK, I guess that’s all for now. Have a nice day everyone. Hope the weather is as nice wherever you as it is here. I think the last snow in my street will melt today :-)

    - BMD

  • #2
    Come on: Don't tell me no one here has ever fired a .50 caliber?!

    I could really use some help here so I'll try again and hope someone is in a kind mood today:

    1 - How common are stoppages or jams with the .50 cal in your experience?

    2 - How small target groups do you shoot with it?


    -BMD

    Comment


    • #3
      Originally posted by BMD
      Come on: Don't tell me no one here has ever fired a .50 caliber?!

      I could really use some help here so I'll try again and hope someone is in a kind mood today:

      1 - How common are stoppages or jams with the .50 cal in your experience?

      2 - How small target groups do you shoot with it?


      -BMD
      I'm sure there are enlisted on this board, it's just they are too busy debating on China vs India thread :-)

      I couldn't help you with these questions, I dont shoot .50 cals, I do something a bit larger. Try pm the mods, that's what they are for

      Comment


      • #4
        OK, Thanks for the tips. I'll wait the smoke to clear in the China-India-thread and maybe spice things up by adding some butter cookies. They seem to be really popular around here :-)


        -BMD

        Comment


        • #5
          Originally posted by BMD
          Come on: Don't tell me no one here has ever fired a .50 caliber?!

          I could really use some help here so I'll try again and hope someone is in a kind mood today:

          1 - How common are stoppages or jams with the .50 cal in your experience?

          2 - How small target groups do you shoot with it?


          -BMD
          If your m2 is jamming then you did something wrong or the weapon is broke. Its probably the most reliable weapon that I have been assigned. If it wasnt it would not still be in the Army inventory

          It depends on range, but its not too hard to hit human size targets out past 600 meters or so after adjustments. With it mounted on the M1A1 its more accurate than that.

          Comment


          • #6
            Oh and hello everyone. I did'nt leave you guys hanging, just wasnt interested in discussing the best tank in the world. or this vs this

            Comment


            • #7
              Originally posted by BMD
              Come on: Don't tell me no one here has ever fired a .50 caliber?!

              I could really use some help here so I'll try again and hope someone is in a kind mood today:

              1 - How common are stoppages or jams with the .50 cal in your experience?

              2 - How small target groups do you shoot with it?
              1. Rare to never. I've shot them with to much lube, no lube, Glowing hot tube(to the point of causing a runaway gun) and could probably count on 1 hand the times I've had problems with them.

              Was your headspace set properly?

              The only other thing I could think of is a dirty feed tray, worn extractor or feed pawl.


              2. Well until the Canadians beat it. The longest sniper shot was taken with a Ma Deuce.

              But not sure what you mean by the question.

              3 - Most mounts for the M2 use just the spade grips as user interface (no shoulder bar as in the Vinghoeg mount). It seems to me that must make the weapon bounce around a lot while firing. Is it possible to use the sights while firing automatic that way?
              No, the the T&E provides stability from the tripod


              4 - In my limited experience the M2 has jammed a lot. Possibly as much as once or twice every 100 rounds. I've never used the Mk 19 or HK GMG. Anyone else who has better experiences?
              I've shot them with to much lube, no lube, Glowing hot tube(to the point of causing a runaway gun) and could probably count on 1 hand the times I've had problems with them. That in over 20 yrs. M2s are as close to Marine proof as any weapon made.

              5 – The M 240 / MAG 58 has 3 different rate of fire settings. Which setting is used when? Or are the two higher settings just for when the weapon is dirty?
              First setting normally used. Other 2 increase the RoF, but as you said normally used when the weapon is dirty to keep it from jamming in the ground mount. Actually used to change the RoF in the AC and coax mount.
              Last edited by Gun Grape; 07 Jun 06,, 03:50.

              Comment


              • #8
                Originally posted by BMD
                2 - How small target groups do you shoot with it?

                -BMD
                A HMG is an area weapon hence one does not calculate "grouping fire" as one would for a rifle. For MGs/ HMGs you check the "beaten zone". The beaten zone increases with the increase in range and varies with the type of mount used.
                5 – The M 240 / MAG 58 has 3 different rate of fire settings. Which setting is used when? Or are the two higher settings just for when the weapon is dirty?
                Gun Grape has already explained, however, just to add, the last gas regulator position or no. 3 slot is used when the weapon is in AA role.

                Cheers!...on the rocks!!

                Comment


                • #9
                  Thanks a lot for your feedback guys. This is getting really interesting.

                  Stoppages:
                  If your m2 is jamming then you did something wrong or the weapon is broke. Its probably the most reliable weapon that I have been assigned. If it wasnt it would not still be in the Army inventory
                  I'm not sure jamming is the right word. All the stoppages I've had have been easily remedied by pulling the charging handle to load a new round. Are you guys saying the simple stoppages I've experienced are practically eliminated by correct headspace adjustment?

                  The only serious failure I've seen was when a guy in my squad managed to break a pin in the bolt during handling.

                  Accuracy:
                  It depends on range, but its not too hard to hit human size targets out past 600 meters or so after adjustments. With it mounted on the M1A1 its more accurate than that.
                  Great! This is exactly what I'm looking for. So you would say at 600m on a tripod with T&E the rounds of each burst would be dispersed within a 1-to-2-metre diameter circle or so? Or less? And on the M1A1? Is the .50 cal on the CWS hardmounted or on a soft mount like the Mk 93?

                  What I'm looking for is any measurement of bullet dispersion at a given range and with a given mount so I can translate it to MOA or NATO mils.
                  The point is to get an idea of achievable precision with different types of mounts.

                  Use:
                  The norwegian army manual on medium machine guns states that they should work in pairs, start in opposite ends of the target area and distribute 1-2 bullets per metre of target.

                  Is the drill for HMGs similar? Or is the heavier ammunition used more for concentrated fire against vehicles and point targets in light cover and less for area suppression?

                  How about the Mk 19? Anyone used it?

                  Comment


                  • #10
                    Originally posted by BMD
                    Use:
                    The norwegian army manual on medium machine guns states that they should work in pairs, start in opposite ends of the target area and distribute 1-2 bullets per metre of target.
                    It that deployment of the MMG during defence or attack?

                    Cheers!...on the rocks!!

                    Comment


                    • #11
                      Originally posted by BMD
                      Thanks a lot for your feedback guys. This is getting really interesting.
                      To answer just about all your questions refer to the "Bible"
                      MCWP(MArine Corps Warfighting Publications) 3-15.1 Machine guns and Machine Gun Gunnery

                      It answers all the questions that you have asked plus gives indirect fire tables for the 240G, the Ma Deuce and Mk 19.

                      Comment


                      • #12
                        Originally posted by Gun Grape
                        To answer just about all your questions refer to the "Bible"
                        MCWP(MArine Corps Warfighting Publications) 3-15.1 Machine guns and Machine Gun Gunnery

                        It answers all the questions that you have asked plus gives indirect fire tables for the 240G, the Ma Deuce and Mk 19.

                        Here is a link to a PDF , However when I downloaded it the indirect firing tables are blank. Covers the M-240G, M-2 and Mk-19

                        www.interordnance.com/library/Marine Corps Machine Gunnery manual.pdf

                        Comment


                        • #13
                          Originally posted by BMD
                          Stoppages:
                          I'm not sure jamming is the right word. All the stoppages I've had have been easily remedied by pulling the charging handle to load a new round. Are you guys saying the simple stoppages I've experienced are practically eliminated by correct headspace adjustment?

                          The only serious failure I've seen was when a guy in my squad managed to break a pin in the bolt during handling.
                          No your failure to feed problem is because of one of the following usually.

                          1. Worn feed pawls, feed mech

                          2. Dirty feed mech/tray

                          3. Ammo not straight. How were you feeding it?


                          The other thing I've seen, how many rounds had piled up under the gun? Could have had a blockage and cycling through dislodged it.

                          I shouldn't have put down Headspace for stoppages. If it wasn't firing at all or firing before the bolt went all the way home, then you normally have a headspace problem.

                          Comment


                          • #14
                            Sorry about the delay. I've been away on a seminar (and a bachelor party). Among other things I got to try the new HK GMG with Vinghoeg's laser-rangefinding electronic sight (and softmount). Impressive accuracy!

                            To Gun Grape:
                            Thanks for the link!
                            I get a "cannot find server" error though. Both from the link you gave me and when I click my way through www.usmc.mil. Hopefully it's just that the server is down, but it might be that access is denied for non-US URLs.

                            About the stoppagages on the .50 cal: If I remember correctly the rounds fed OK, or at least partially, it just failed to fire. So when I pulled the charging handle, the unfired round was extracted just like a spent casing. The gun was fed from the normal ammo box mounted beside the gun, the rounds were clean and the pile of spent casings was swept aside before it got anywhere close to the gun.

                            Lemontree:
                            It din't say. But I'm guessing it was used as a way of saying "don't go running around here" both to attackers and defenders/reinforcements trying to relocate. The tripods had a mechanism that would mechanically traverse the weapon a little bit for each round fired so as to get an even distribution of rounds. True world war one style. AFAIK the tripod is phased out of the Norwegian army these days. Not sure whether that's a good thing.

                            Comment


                            • #15
                              Originally posted by BMD
                              Lemontree:
                              It din't say. But I'm guessing it was used as a way of saying "don't go running around here" both to attackers and defenders/reinforcements trying to relocate. The tripods had a mechanism that would mechanically traverse the weapon a little bit for each round fired so as to get an even distribution of rounds. True world war one style. AFAIK the tripod is phased out of the Norwegian army these days. Not sure whether that's a good thing.
                              Its a good thing that the WW1 tripod was phased out. In defence you place the MMGs at the flanks of a company defended locality (in plains) to provide enfilade fire. Lay the MMG rear sight at 600 mtrs and aim at any target at a distance, so when you fire the rounds will not rise above 4 ft from the ground, enough to kill/ wound advancing enemy troops. The MMG is deployed very low to the ground, and at night one does not even have to aim, if the enemy is advancing just keep firing shot 3-4 rd bursts.
                              Last edited by lemontree; 13 Jun 06,, 12:56.

                              Cheers!...on the rocks!!

                              Comment

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