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  • #16
    I think that there is probably a bigger market for sabot ammunition for shotguns than rifles, as all the major ammo manufactures have sabot rounds in their shotgun line.

    http://www.nrapublications.org/tah/Slugs.asp
    Home, down in the valley behind the Red Angus
    Bad Decisions Make Good Stories​

    Location: British Columbia

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    • #17
      Geeze, I hope that they aren't illegal in Canada.
      After the last round of gun laws they made .50 cal illegal here, don't know if that applies to this situation or not. I have some 12 ga. sabot ammo too, oh well now everybody knows, I'll expect the ammo Nazis will be at my door in the AM.
      Home, down in the valley behind the Red Angus
      Bad Decisions Make Good Stories​

      Location: British Columbia

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      • #18
        The mythbusters chicken gun packs a punch and uses a sabot

        I love that show.

        http://www.youtube.com/watch?v=lTW_Or5ezPk

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        • #19
          i have a ton of the .30 cal. sabot rounds laying around. they are not very accurate. they would more appropriately be called "sub-caliber rounds", as their main purpose is to allow the use of smaller caliber bullets in a larger caliber bore. an actual sabot round, as used in the M1 tanks is a completely different beast.

          there are sabot shotgun rounds available. they are basically a bunch of small darts packed inside a plastic carrier. nothing like the .30 cal. Accelerator rounds mentioned. they are lethal only because there are 100 of them flying at you and the chances of puncturing a vital area are greater than a single slug hitting a vital area.

          in general, the muzzle energy of a lighter round (sabot or sub-caliber) for a given caliber is less than a heavier round. this is because you can only pack so much powder in a cartridge and can only achieve so much velocity from the ignition efficiency. the M1 tank sabot rounds were designed from the ground up as a sabot round and can make use of the special properties of the projectile. there also is no human shoulder to worry about injury from recoil. attempting to fire sabot ammunition from a "normal" firearm designed for normal non-sabot ammunition will generally provide less than ideal results. the Raufoss SLAP ammo is an exception. but i would guess a tungsten/.50 BMG combo would be deadly no matter what the configuration.

          andy b.
          The danger is not that computers will come to think like men - but that men will come to think like computers. - some guy on another forum not dedicated to machining

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          • #20
            What hasn't been mentioned is the military sabot projectiles are long and skinny like a dart to give them sectional density to give them better range at high velocity and very dense material for greater range and prenetrating power.

            If a 22 cal weight round projectile was made into a 0.08" dia flechette config and encased in a light weight discarding sabot in a 30 cal case you could conceivably have a 10,000 ft/sec muzzle velocity five times that of a conventional round. Short range target damage would be out of proportion in harder targets but as hunting ammo, what?

            Tank ammo isn't known for long range accuracy. It's strictly for line of sight short range encounters against other tanks and hard targets. For trucks at the same 1000 meter range the M2 is probably a better choice. Certainly more cost effective per destroyed target.

            Interesting question, though. Somebody has to run experiments.
            Last edited by Forrest Addy; 08-27-2007, 10:09 PM.

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            • #21
              [QUOTE=Lee in Texas]Awesome thread. I was a crewman in an M1A1 Abrams. I loved that machine.

              A .22 projectile fired out of a .45 would move faster, but since the .22 projectile is not engaging the rifling, it will likely be extremely unstable in flight. Sabots need fins to have a stable flight. Some rifled tank guns fire sabots, but they have bearing in the sabot to allow the projectile to "slip"; spinning much slower than a conventional round.

              Lee, in modern centerfire ammunition loaded with sabots and sub caliber projectiles for rifles and pistols (and a few shotguns with light rifling in the last few inches of the bore), the sabot grips the projectile tightly, and the spin imparted to the sabot by the barrel's rifling is translated to the projectile.
              When the two separate the projectile is still spinning and is stabilized as though it had fit the bore it was fired from perfectly.

              The most common formula used for calculating the muzzle energy (can be used for down range energy as well) for firearms is velocity squared, times the projectile weight in grains, the result divided by the constant of 450240 (sometimes listed as 450450 in some reloading manuals). This will yield the energy of the projectile in foot pounds.

              By the way, thanks for serving your country in those tanks!
              Steve
              NRA Life Member

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              • #22
                Originally posted by andy_b
                there are sabot shotgun rounds available. they are basically a bunch of small darts packed inside a plastic carrier.
                -Two different items. Yes, there's a "flechette" round (not commonly) available for the shotgun, but more commonly available are BRI-style saboted slugs. They're a true sabot round, firing a .50 caliber wasp-waisted slug.

                Doc.
                Doc's Machine. (Probably not what you expect.)

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                • #23
                  Ballistic Coefficient

                  The question of whether a sabot round is effective for a particular purpose depends upon the aerodamic/ballistic characteristics of the projectile at a particular velocity range. Several posts alluded to it without using the term, "balistic coefficeient." In general larger projectiles have better ballistic coefficients, that is they retain energy in for the form of velocity at longer ranges, but a for a given case, the larger the bullet the lower the velocity. Decrease the size of the bullet, increase the velocity but decrease the ballistic coefficient. You have to decide what you want, long or short range, flat trajectory or not, energy retention at range, or short range, etc.

                  Graph it out and it may be that a sabot will be the ideal solution, but chances are, as Doc said, an existing conventional design will work almost as well and probably with better accuracy.
                  Ed Bryant

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                  • #24
                    Originally posted by Forrest Addy
                    What hasn't been mentioned is the military sabot projectiles are long and skinny like a dart to give them sectional density to give them better range at high velocity and very dense material for greater range and prenetrating power.
                    BigBoy mentioned long rod penetrators on the first page Forrest.

                    Tank ammo isn't known for long range accuracy.
                    Direct fire yes, but modern tanks are very accurate at long range. The M1 is accurate out to 8,000 meters (5 miles).

                    It's strictly for line of sight short range encounters against other tanks and hard targets. For trucks at the same 1000 meter range the M2 is probably a better choice.
                    Modern battle tanks are equipped with two ammo loads: long rod penetrators for hard targets (other tanks) and HEAT rounds for soft targets.

                    Lee: I was an electrical engineer for the Army Research Laboratory for many years, and I spent many months out in the field at White Sands Missile Range testing research prototypes against M1 tanks driving in circles in the desert. A couple of times the CO let me drive one of the Abrams for short distances with the hatch up. What an amazing machine! The first time I hit the throttle (it's a twist throttle, like a motorcycle) and turned 1500 horsepower loose on 70 tons, which rocked the carriage backward. The CO was not happy, and I thought I was going to have to change my shorts It wasn't a wheelie, but it sure felt like it!

                    The other thing that occurred to me is that the driver is pressed up against the glacis, especially with the hatch down. The tank may survive a direct hit to the glacis, but I sure don't want to know what that shock would do to the driver. The other thing that occurred to me is that the glacis is filled with depleted uranium, which is mildly radioactive, and inches away from the driver's family jewels. No OSHA in the Army...
                    Last edited by lazlo; 08-28-2007, 01:32 AM.
                    "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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                    • #25
                      Originally posted by tattoomike68
                      The mythbusters chicken gun packs a punch and uses a sabot
                      That was freakin' hilarious. Especially when they realized that they were firing chickens against small aircraft windshields that weren't rated for bird impacts. Oops!

                      The Styrofoam chicken sabot was very clever though!
                      "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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                      • #26
                        Originally posted by lazlo
                        BigBoy mentioned long rod penetrators on the first page Forrest.



                        Direct fire yes, but modern tanks are very accurate at long range. The M1 is accurate out to 8,000 meters (5 miles).
                        Not quite that far. How far? Eh...I've heard stories. The longest I've heard of is about 4,000 meters. The limitations of the sights and rangefinder come into play here. The M1A2SEP has a sight that goes up to 50x, so who knows? Also, the Leopard 2A6 has the same gun but IIRC the tube is a full meter longer. The goal was to get their tungsten sabots to have the same energy as our DU rounds. That extra velocity could likely extend the range. They were working on a 140mm gun, but that was sadly not to be.



                        Modern battle tanks are equipped with two ammo loads: long rod penetrators for hard targets (other tanks) and HEAT rounds for soft targets.
                        And, bless their hearts, they have a beehive round once again. Essentially a 120mm shotgun round.

                        Lee: I was an electrical engineer for the Army Research Laboratory for many years, and I spent many months out in the field at White Sands Missile Range testing research prototypes against M1 tanks driving in circles in the desert. A couple of times the CO let me drive one of the Abrams for short distances with the hatch up. What an amazing machine! The first time I hit the throttle (it's a twist throttle, like a motorcycle) and turned 1500 horsepower loose on 70 tons, which rocked the carriage backward. The CO was not happy, and I thought I was going to have to change my shorts It wasn't a wheelie, but it sure felt like it!
                        Hey cool. I spent a year at WSMR guarding. Eh. Well, you probably know what I was guarding.

                        Once at Ft Hood, I got to take the C.O.'s tank to the range. Just me and the driver for 15 or so miles. I had him open it up. One of our soldiers was on the tank trail in a Humvee and swears we were airborne, but this kid can tell some stories so who knows? We were hauling @$$ though.

                        The other thing that occurred to me is that the driver is pressed up against the glacis, especially with the hatch down. The tank may survive a direct hit to the glacis, but I sure don't want to know what that shock would do to the driver. The other thing that occurred to me is that the glacis is filled with depleted uranium, which is mildly radioactive, and inches away from the driver's family jewels. No OSHA in the Army...
                        I never worried about the DU surrounding me. It is encased in steel. There was one thing in the back of my mind though. Taking a hit head-on. Even if the round didn't penetrate, it could send some nasty spall at me. Overall, I loved that machine. It broke my heart when the Texas national Guard lost tanks. I will not be reenlisting. The thrill is gone.

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                        • #27
                          The record, IIRC, is around 4800 meters in the initial invasion of Iraq in 2003.

                          Yes, it's a shame they never went to the 140mm developed at Picatinny - it was decided that since the current 120mm is capable of killing just about any MBT in the world, and the 140mm would mean mandatory autoloaders, and reduced ammunition capacity, as well as a new turret. The Army decided to instead focusing on improving the ammo. Which now puts it on Par with the longer L/55 Rheinmetall gun used on the New Lepards. Since We're still using an Americanized version of the L/44, updating to L/55, along with our new long rod penetrator, gives us 90% of the advantage of the 140mm, and none of the disadvantages.

                          And oh, one of the things they're seriously looking into, is combustable cases - easier to deal with.

                          The DU Armor is being redesigned in light of the NRC's lowering the exposure limit for armor crews from 500 millirems a year, to 100 millirems.

                          Nothing using direct acting gunpowder is going to get a projectile faster than 6800 feet/sec using Nitro based powder, because of inertia - the gas is too heavy(to go faster you need a "Light gas" gun) The Long rod penetrator we use travels about 5700 ft/sec. The big advantage of Sabot rounds is this: Despite them being smaller in diameter, they still have the entire surface area for the gas to act upon. That's why if you took a .30-06 "accelerator", it would be faster than simply necking the case down. It's easily demonstrated by looking at the muzzle energy of cartridges that are necked up and down, and comparing powder charges and muzzle energy.

                          And oh, the reason why the Accelerator line failed commercially was because they had horrible accuracy. You couldn't hit the broad side of a barn with it.


                          HTRN
                          EGO partum , proinde EGO sum

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                          • #28
                            Originally posted by Lee in Texas
                            Not quite that far. How far? Eh...I've heard stories. The longest I've heard of is about 4,000 meters. The limitations of the sights and rangefinder come into play here. The M1A2SEP has a sight that goes up to 50x, so who knows?
                            That's where I got the 8,000 meters -- the contractor spec on the M1A2 FEP (Firepower Enhancement Package) was 8,000 meters:

                            "FEP also includes an eyesafe laser rangefinder, north-finding module and precision lightweight global positioning receiver which provide targeting solutions for the new Far Target Locate (FTL) function. FTL gives accurate targeting data to a range of 8,000m."

                            And, bless their hearts, they have a beehive round once again. Essentially a 120mm shotgun round.
                            Wow, they re-invented grape-shot? Was that developed for Iraq? Are the sub-munitions active (explosive)?

                            Once at Ft Hood, I got to take the C.O.'s tank to the range. Just me and the driver for 15 or so miles. I had him open it up. One of our soldiers was on the tank trail in a Humvee and swears we were airborne, but this kid can tell some stories so who knows? We were hauling @$$ though.
                            That was the other thing that really struck me about the Abrams -- the ride was amazingly smooth. I'd never been in a tank before, let alone ridden in one, but I was expecting a bone-jarring ride. But that Cadillac suspension system is sweet!

                            There was one thing in the back of my mind though. Taking a hit head-on. Even if the round didn't penetrate, it could send some nasty spall at me.
                            I had that picture in my mind too Lee -- in the crew compartment you've got three guys cramped together in something like a 3 foot circle. If something did penetrate the armor, or worse, a top-attack EFP, it seems like any resulting spall would kill the entire crew in a hearbeat (although the driver is sealed-away up front).

                            Tough business to be in...
                            "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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                            • #29
                              Why has nobody discussed the twist rate of the parent weapon's rifling vs. the proper twist rate for the caliber of the sabot round? That will have a tremendous effect on the accuracy of the sabot due to instability.
                              Lynn S.

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                              • #30
                                We don't need no stinkin' sabots

                                http://maggiesfarm.anotherdotcom.com...us-Recoil.html

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