Something interesting, the British tanks autoloader

[Molota_477]

When I read a book in Chinese ''坦克技术概论'',I found a pic showed below, it looks like a T-72s autoloader,but actually it was mounted on British tank,maybe the Centurion.I try to search for the source but I failed.

Is there anyone have more information about it?

[Khand-e]

I'm honestly drawing nothing but blanks on what British tanks used an autoloader even experimentally.

 

Does it say anything about the shell diameter?

[Molota_477]

According to the notes, this automatic loading system is developed by Air-Log limited company(I have no idea about it).And the shells maybe 110mm, I guess. The gun breech looks like the one in MBT80 ATR1.

[Khand-e]

110mm? Judging by that, I'm guessing it's for the British rifled gun they pitched to the US as an upgrade to for XM1 Abrams before the 120mm M256 was ultimately chosen.

[Collimatrix]

I can't see the picture.  Could you re-upload to imgur?  That usually works.

[Khand-e]

I can't see the picture.  Could you re-upload to imgur?  That usually works.

 

[Khand-e]

By the way, after searching, it would appear that the exact model of gun, judging by the projectiles and propellant charges depicted in the photo, are that of the EXP-14 series, apparently there was alot more then just 1 simple 110mm design but a rather long series of 110mm and eventually 120mm gun systems that ultimately lead to the L30 according to Colli.

 

http://www.bocn.co.uk/vbforum/threads/39366-Experimental-110-apds-tank-round

 

I had to sign up here to see them, but this man has some inert EXP-14 charges and projectiles that look identical.

[Molota_477]

By the way, after searching, it would appear that the exact model of gun, judging by the projectiles and propellant charges depicted in the photo, are that of the EXP-14 series, apparently there was alot more then just 1 simple 110mm design but a rather long series of 110mm and eventually 120mm gun systems that ultimately lead to the L30 according to Colli.

http://www.bocn.co.uk/vbforum/threads/39366-Experimental-110-apds-tank-round

I had to sign up here to see them, but this man has some inert EXP-14 charges and projectiles that look identical.

I have created an account of there but have no permission to see the attachments

[Khand-e]

I have created an account of there but have no permission to see the attachments

 

Have to wait for a mod to approve you, it took me a few hours.

[Toxn]

Interesting - it looks like a two-part ammunition setup (which fits for both autoloaders and the British) that tracks the gun breech. Depending on when it was developed, this might either be a pretty smart move or the dumbest thing ever. 

[Collimatrix]

I believe it's some iteration of this series of 110mm ammo development, third from left in this picture, which LooSeR posted before:

 

 

 

Xlucine explained this to me over teamspeak.  Remember how an L7 is basically just a 20 pounder with a wider bore and the cartridge case necked out to 105mm?  The Brits tried to get lightning to strike again by necking out the case one more time, 'til it was completely straight-walled to make a new 110mm gun.  The idea was to have something that would be an easy drop-in upgrade for the L7, just like how the L7 was an easy drop-in upgrade for the 20 pounder.  Since basically all of NATO except the British were using L7s at this point, the potential sales were enormous.

 

Guns are basically piston engines that throw their pistons down range, so going up in caliber is basically the same thing as boring out the cylinders in a motor.  But the difference in swept volume between a 105mm tube and a 110mm tube isn't enormous; a little less than 10%.  So to get more performance they started running up the pressures.  This led to the cases sticking and not extracting properly, so they went to a semi-combustible case design, which is what you see above.

 

As the gun was developed further, the case stub got smaller and smaller until it went away entirely and the design was switched to bagged ammo.  Only thing was, by this point the pressure was so high that the breech obturator ring design from the L11 would not work and they had to come up with something better.  This breech design was recycled in the 120mm L30 on the challenger 2.  So there you go; despite using the same HESH ammunition, the L30 is actually a development of the L7, not the L11.

 

Like most ideas in British tank design, the 110mm EXP-7/EXP-14/EXP-whatever was obsolete by the time it was ready for prime time.  The British were completely, stubbornly convinced that rifled guns firing APDS were the way to go, well into the 1970s when everyone else in NATO had stopped dicking around with gun-launchers and figured out that smoothbore and APFSDS were the correct choice.  As usual they were way behind the Soviets, whose T-62 design had a smoothbore gun, had already seen combat, and was already in the process of being replaced with a next generation vehicle!

 

You can also see that it uses two-piece ammo, which is basically the way to go if you're firing APDS.  It also looks like some of the propellant charge lives with the sabot.  Very Soviet.

 

Oddly, this exact diagram shows up as a generic diagram for an autoloader on the army-guide article on autoloaders.

[Collimatrix]

I take it back, that's not propellant living with the sabot.  That's two rows of big propellant charges.  It's totally unclear to me from that picture where the projectiles live.  Is that smeared blur near the middle of the carousel the sabot?  Is this like a double-stacked T-72 autoloader?  If so then how the hell did they plan on shooting their beloved HESH rounds?

 

British tank design is Kurt Cobain; occasional spasms of cleverness amidst a corpus of generally mediocre work that is for some reason praised to the heavens.  HESH is their Courtney Love; a weird dalliance from the past that they have indecorously and inexplicably held to that is holding them back and making them do stupid things.  Also both British tank design and Kurt Cobain are dead.

[Toxn]

Colli laying the burns on thick and fast, like an incontinent flamethrower.

[Molota_477]

After my compares，this may just be an idea from a small company,never built and have little attraction ,

and we see the rounds holding into the loader （it should be APFSDS，as we can see the saddle shaped sabot is there），it is highly possible a 120mm ammunition，but i can't figure out the date when this idea cames out，not sure is it reference the same idea from T-72 .

[Khand-e]

After my compares，this may just be an idea from a small company,never built and have little attraction ,

and we see the rounds holding into the loader （it should be APFSDS，as we can see the saddle shaped sabot is there），it is highly possible a 120mm ammunition，but i can't figure out the date when this idea cames out，not sure is it reference the same idea from T-72 .

 

It was built into several series, and eventually evolved into the L30 used on the Challenger series of tanks, but it didn't achieve it's goal of getting full NATO approval like the L7 did that the British were hoping for. Which was mostly due to the Rheinmetall 120mm L/44 and later L/55 winning out instead in most countries, or some countries developing their own guns that fired the same ammunition as the Rheinmetall. (The Leclerc and Merkava are examples of tanks that use the 120mm NATO chambering but don't use the Rheinmetall gun.)

 

Colli's explanation sums it up pretty well.

[Molota_477]

Yeah, thats ture

[Collimatrix]

More information on the British 110mm series of weapons:

http://www.tank-net.com/forums/index.php?showtopic=34275

 

http://www.tank-net.com/forums/index.php?showtopic=12714&page=36

[Molota_477]

More information on the British 110mm series of weapons:

http://www.tank-net.com/forums/index.php?showtopic=34275

http://www.tank-net.com/forums/index.php?showtopic=12714&page=36

Thank you Colli.