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  • Willy
    replied
    Originally posted by dicks42000
    Willie;
    I don't want to fan any flames, but iirc, some of the local west coast natives are/ have negotiated the right to hunt whales and if they follow suite with other tribal groups south & north of 49, the weapon of choice is a .50 cal. rifle...Do they have some kind of exemption...?
    Rick
    Not that I'm aware of Rick. I have just spent the better part of three hours trying to find that exemption in the firearms act, and as of yet I haven't found it. But as I'm sure you can imagine it is a very convoluted and ambiguous piece of legislation. I could be there for three weeks and not know any more than I do now. Lawyers make laws so that they will have a job interpreting the laws that they wrote.
    For all I know it could be tied into some kind of international aboriginal treaty, there are a number of those because of tribal boundaries crossing the U.S./Can. border.
    Interesting point though Rick as I too have seen news footage of them using .50 cal firearms in their whaling endeavors.

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  • Lee in Texas
    replied
    Originally posted by lazlo
    I thought all the M1 rounds had combustible cases, including the original M829A1 (the "Silver Bullet").
    They are. The IPM1s (initial production) had 105mm rifled guns and brass cases. M1A1 and up have smoothbore 120s with combustible case ammo. All IPs have been retired.

    I would love to light up a car bomber with that canister round. I have some friends who went to Iraq. They were in Humvees engaging a couple of cars across the Tigris. A tank rolled up and the TC said "Do you mind if we light 'em up? We're bored as hell." They said have at it. Our guys heard that the battle damage assessment team wasn't sure how many bodies were at the scene.

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  • lazlo
    replied
    I thought all the M1 rounds had combustible cases, including the original M829A1 (the "Silver Bullet").

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  • HTRN
    replied
    It appears they have indeed started adopting combustable cases - that XM1028 is one, and the latest version of the APFSDS, the M829A3, a fourth generation "silver bullet"(penetrates almost 700mm of RHA @ 2 kilometers, and specifically designed to defeat reactive armor), also uses it.

    It seems conventional cases are being phased out for tank ammunition.

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  • lazlo
    replied
    Originally posted by Lee in Texas
    And, bless their hearts, they have a beehive round once again. Essentially a 120mm shotgun round.
    I just found the M1028 Cannister Tank Cartridge on GlobalSecurity.org: the cartridge contains 1150 tungsten balls. Can you imagine the carnage?

    http://www.globalsecurity.org/milita...ions/m1028.htm

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  • dicks42000
    replied
    .50 cal illegal in Canada now.....?

    Willie;
    I don't want to fan any flames, but iirc, some of the local west coast natives are/ have negotiated the right to hunt whales and if they follow suite with other tribal groups south & north of 49, the weapon of choice is a .50 cal. rifle...Do they have some kind of exemption...?
    Rick

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  • ckelloug
    replied
    Apparently, if you use the ballistic tables in the operating manual instead of the targeting computer in the M1, you can get beyond the 5km range where the computer won't do the ballistic solution. A couple of colleagues who were M1 Master Gunners told me some stories of doing this in Desert Storm. My understanding is that this limitation in the computer has to do with doctrine as the army doesn't really want tanks engaging things that far down range.

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  • Guest's Avatar
    Guest replied
    Seen it.again.

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  • Boomer
    replied
    We don't need no stinkin' sabots

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

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  • Lynn Standish
    replied
    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.

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  • lazlo
    replied
    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...

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  • HTRN
    replied
    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

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  • Lee in Texas
    replied
    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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  • lazlo
    replied
    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!

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  • lazlo
    replied
    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.

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