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  • #31
    Originally posted by cr9527 View Post
    I guess, I can never tell the difference between all of the AR-15 variants, copies, or descendants..
    Type 65 doesn't have the integral carry handle (but not a flat top like the current trend). I believe it's also a piston driven design rather than direct gas impingement.

    Originally posted by cr9527 View Post
    By the way, how come the states doesn't use any wheeled self propelled howitzers? (not towed)
    That's because we drive everyday of our lives and are sick of it.

    I'm just kidding. I have no idea why we don't use wheeled SPH. Actually, I suspect OOE asked the right questions about wheeled SPH. It doesn't offer enough mobility like tracked vehicles but uses too much resources if we fix guns onto their own truck platforms. Basically too little one way and too much the other.
    Last edited by gunnut; 21 Feb 11,, 21:27.
    "Only Nixon can go to China." -- Old Vulcan proverb.

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    • #32
      Originally posted by gunnut View Post
      Type 65 doesn't have the integral carry handle (but not a flat top like the current trend). I believe it's also a piston driven design rather than direct gas impingement.
      Well in that case, they could be M16s or M4s, form the length of the barrel, probably the M4.


      That's because we drive everyday of our lives and are sick of it.

      I'm just kidding. I have no idea why we don't use wheeled SPH. Actually, I suspect OOE asked the right questions about wheeled SPH. It doesn't offer enough mobility like tracked vehicles but uses too much resources if we fix guns onto their own truck platforms. Basically too little one way and too much the other.
      So the US Army doesn't want an intermediate between a tracked SPH and a towed howitzer?

      Are others opting for this option to save costs from buying a tracked SPH?

      Comment


      • #33
        Originally posted by S-2 View Post
        These systems would require a dedicated ammo supply vehicle or, minimally, a damned big trailer.
        carry the gun and pull a ammo trailer ? would that weight be a mobility kill by itself ?
        J'ai en marre.

        Comment


        • #34
          Towed vs Truck Mounted vs Tracked Self Propelled

          To be honest I dont see the point of Truck Mounted Howitzers myself. As others have pointed out they have all the disadvantages of both Towed and Tracked SPH rolled into one package.

          Disadvantages of Truck Mounted Howitzer:

          Crew exposed.
          As Maintenance Intensive as a Tracked SPH
          Rate of Fire, Emplacement and Displacement times not appreciably faster than a modern towed system. (Proven by British Army during a comparative asseesment of Caeser vs M777/Portee System)
          Limited on Carriage Traverse.
          Tactical Mobility less than a Tracked SPH
          Tactical Mobility less than a Towed Howitzer when Airlift options considered.

          Advantages of Truck Mounted Howitzer:

          Lighter than a Tracked SPH means Strategic Mobility easier.
          Reduced Lane Length compared to Towed Plus Prime Mover.
          Capable of mounting 45 or 52 Cal tube compared to 39 Cal in M777, Pegasus.
          Smaller Crew size than Towed. (However this can impact crews ability to perform Daily Maintenance and sustain 24/7 operations)

          Those are the main things that I can think of just of the top of my head.

          Regards

          Arty
          "Admit nothing, deny everything, make counter-accusations".- Motto of the Gun Crew who have just done something incredibly stupid!!!!

          Comment


          • #35
            Originally posted by ArtyEngineer View Post
            To be honest I dont see the point of Truck Mounted Howitzers myself. As others have pointed out they have all the disadvantages of both Towed and Tracked SPH rolled into one package.

            Disadvantages of Truck Mounted Howitzer:

            Crew exposed.
            As Maintenance Intensive as a Tracked SPH
            Rate of Fire, Emplacement and Displacement times not appreciably faster than a modern towed system. (Proven by British Army during a comparative asseesment of Caeser vs M777/Portee System)
            Limited on Carriage Traverse.
            Tactical Mobility less than a Tracked SPH
            Tactical Mobility less than a Towed Howitzer when Airlift options considered.

            Advantages of Truck Mounted Howitzer:

            Lighter than a Tracked SPH means Strategic Mobility easier.
            Reduced Lane Length compared to Towed Plus Prime Mover.
            Capable of mounting 45 or 52 Cal tube compared to 39 Cal in M777, Pegasus.
            Smaller Crew size than Towed. (However this can impact crews ability to perform Daily Maintenance and sustain 24/7 operations)

            Those are the main things that I can think of just of the top of my head.

            Regards

            Arty
            Alrighty, thank you

            Comment


            • #36
              AE, what are the stability issues with a wheeled chassis vs. a tracked chassis? It seems to me a wheeled chassis would tend to be less stable than a tracked chassis, partly because of the smaller footprint.
              "There is never enough time to do or say all the things that we would wish. The thing is to try to do as much as you can in the time that you have. Remember Scrooge, time is short, and suddenly, you're not there any more." -Ghost of Christmas Present, Scrooge

              Comment


              • #37
                Stitch

                Originally posted by Stitch View Post
                AE, what are the stability issues with a wheeled chassis vs. a tracked chassis? It seems to me a wheeled chassis would tend to be less stable than a tracked chassis, partly because of the smaller footprint.
                Management of Recoil Forces on any Howitzer is a primary design driver. But especially so on a Truck Mounted System. As "Scotty" says "Ye cannae change the laws a physics".

                On any truck mounted system you are dealing with less Mass than a Tracked System, a Higher Center of Gravity and a Line of Action of the Recoil Forces which creates a significant Moment wanting to flip your whole contraption over!!! For this reason the Caeser for example has a more limited "Traverse Arc" than the M777 or the M198 before it. Both the M777 and M198 had 400 mils (22.5 Deg) left and right of center. Caeser is restircted to 300 mils (17 Degrees approx) left and right of centre.

                It also has a large platform it Hydraulically drops into the ground and actually lifts the rear of the truck of the deck so that the suspension system is not seeing these recoil forces. See Pic:



                To give you some idea of the forces involved a JBMOU Compliant 39 Cal Tube can see chamber pressures in excess of 56000 psi when firing top charge. This peak pressure starts the acceleration of a 100lb projectile to in excess of 2.5 times the speed of sound over a distance of about 20ft in a time frame measured in milliseconds.

                To descibe the forces as "Extreme" would be an understatement, they are fecking brutal.

                A common misconception however is that Howitzer that whips around and jumps all over the place when firing is "Inaccurate" or "Imprecise" In fact teh projectile is long gone before the weapons system has really had time to react to teh forces excerted on it by the firing. Where inaccuracies can arise is if the weapon is displacing alot and using external aiming references, however with all modern systems having an Inertial Nav system of some sort aligned to teh tube giving pointing information this is no longer an issue.....until your fancy Ring Laser Gyro "Dies" and you got to go back to the old school way of doing things.

                Regards

                Arty
                Attached Files
                "Admit nothing, deny everything, make counter-accusations".- Motto of the Gun Crew who have just done something incredibly stupid!!!!

                Comment


                • #38
                  Originally posted by ArtyEngineer View Post
                  To be honest I dont see the point of Truck Mounted Howitzers myself. As others have pointed out they have all the disadvantages of both Towed and Tracked SPH rolled into one package.
                  Hehehehahahahahahahaha!

                  The French came up with a pretty looking, what looks like a cheap, concept and actually found a few suckers ... the rest followed suit, forcing their own militaries to buy a piece of crap ... to the point that the Chinese made one without an order from their own army.

                  Snake oil salesmen, the French!

                  Comment


                  • #39
                    Originally posted by Stitch View Post
                    AE, what are the stability issues with a wheeled chassis vs. a tracked chassis? It seems to me a wheeled chassis would tend to be less stable than a tracked chassis, partly because of the smaller footprint.
                    Its a centre of gravity issue as well... absolute mass down low with one and higher COG with the other as a critical vector is mobility.

                    "trade offs" cost
                    Linkeden:
                    http://au.linkedin.com/pub/gary-fairlie/1/28a/2a2
                    http://cofda.wordpress.com/

                    Comment


                    • #40
                      Originally posted by ArtyEngineer View Post
                      Management of Recoil Forces on any Howitzer is a primary design driver. But especially so on a Truck Mounted System. As "Scotty" says "Ye cannae change the laws a physics".

                      On any truck mounted system you are dealing with less Mass than a Tracked System, a Higher Center of Gravity and a Line of Action of the Recoil Forces which creates a significant Moment wanting to flip your whole contraption over!!! For this reason the Caeser for example has a more limited "Traverse Arc" than the M777 or the M198 before it. Both the M777 and M198 had 400 mils (22.5 Deg) left and right of center. Caeser is restircted to 300 mils (17 Degrees approx) left and right of centre.

                      It also has a large platform it Hydraulically drops into the ground and actually lifts the rear of the truck of the deck so that the suspension system is not seeing these recoil forces.

                      To give you some idea of the forces involved a JBMOU Compliant 39 Cal Tube can see chamber pressures in excess of 56000 psi when firing top charge. This peak pressure starts the acceleration of a 100lb projectile to in excess of 2.5 times the speed of sound over a distance of about 20ft in a time frame measured in milliseconds.

                      To descibe the forces as "Extreme" would be an understatement, they are fecking brutal.

                      A common misconception however is that Howitzer that whips around and jumps all over the place when firing is "Inaccurate" or "Imprecise" In fact teh projectile is long gone before the weapons system has really had time to react to teh forces excerted on it by the firing. Where inaccuracies can arise is if the weapon is displacing alot and using external aiming references, however with all modern systems having an Inertial Nav system of some sort aligned to teh tube giving pointing information this is no longer an issue.....until your fancy Ring Laser Gyro "Dies" and you got to go back to the old school way of doing things.

                      Regards

                      Arty
                      one of the things I clearly remember from one of the tender evaluations I was involved with was recoil force.

                      eg the TD120 had a recoil force of 15tonnes on the chassis. the accelerometers took a bit of a hiding :)
                      Linkeden:
                      http://au.linkedin.com/pub/gary-fairlie/1/28a/2a2
                      http://cofda.wordpress.com/

                      Comment


                      • #41
                        Originally posted by Officer of Engineers View Post
                        Hehehehahahahahahahaha!

                        The French came up with a pretty looking, what looks like a cheap, concept and actually found a few suckers ... the rest followed suit, forcing their own militaries to buy a piece of crap ... to the point that the Chinese made one without an order from their own army.

                        Snake oil salesmen, the French!
                        Aust Army looked at Caeser and it failed in the opening stages of the assessment. Ironically one of the failure vectors was OH&S for the gunners/loaders having to exit the system under duress. ie ease of movement, inapprop placed components near the gunners seat etc....
                        Linkeden:
                        http://au.linkedin.com/pub/gary-fairlie/1/28a/2a2
                        http://cofda.wordpress.com/

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                        • #42
                          Forgot I had this vid

                          My mate Bob talking about defying the laws of physics!!



                          Regards

                          Arty
                          "Admit nothing, deny everything, make counter-accusations".- Motto of the Gun Crew who have just done something incredibly stupid!!!!

                          Comment


                          • #43
                            weighs about half of any previous 155 mm howitzer that's gone before,
                            Blatant advertising ,
                            the 155 mm Schneider mle 1917C.
                            Last edited by 1979; 23 Feb 11,, 13:30.
                            J'ai en marre.

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                            • #44
                              Originally posted by 1979 View Post
                              Blatant advertising ,
                              the 155 mm Schneider mle 1917C.
                              Yep. thats what happens when you put sales and marketing types in front of a camera at a place like Farnborough Airshow which is where this vid was taken.

                              Regards

                              Arty
                              "Admit nothing, deny everything, make counter-accusations".- Motto of the Gun Crew who have just done something incredibly stupid!!!!

                              Comment

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