Jump to content
Sturgeon's House

Recommended Posts

I am curious how wide IS-7 was.  According to Ogorkiewicz, IS-3 and T-55 were built to the maximum width that Soviet rail gauge could permit two-way cargo.

 

If IS-7 was wider, that would mean that it would be a substantially greater logistical burden to get IS-7s to the front.

Share this post


Link to post
Share on other sites

I am curious how wide IS-7 was.  According to Ogorkiewicz, IS-3 and T-55 were built to the maximum width that Soviet rail gauge could permit two-way cargo.

 

If IS-7 was wider, that would mean that it would be a substantially greater logistical burden to get IS-7s to the front.

Ru wiki syas 3.4 meters. T-54 is 3.27 meters.

Share this post


Link to post
Share on other sites

Even if the AL requires the loaders to move the ready rack conveyor then it's still just like the AL on AMX-13 AIUI.

 

Why the hell didn't it have more ammo? 2.5k is abysmal, chieftain and M60 have twice that (or thereabouts) in the ready boxes for their coaxes. The boolit stool for the gunner was neat, but it sorely needs more MG ammo

Share this post


Link to post
Share on other sites

I was going to ask you about the AMX-13 autoloader.

 

IS-7 doesn't seem to have much internal space; a flaw shared with IS-3.  I'm surprised there's enough turret depth to be comfy with the way the hull cross section is shaped, but then again, there isn't a basket, so maybe it really sucks when the thing rotates.

 

Still scratching my head over when that placard could be referring to if there's no power ammunition conveyor, but who knows.

Share this post


Link to post
Share on other sites

It would be very easy to fit a proper basket to IS-7, since it has the needed rotating floor already. Just add some mesh.

 

 

The IS-7 had a turret basket, a flaw of which was that you had to remove spent casings from or it would jam.

 

Same happens with abramses, per  tanknet at least one abrams turret has been jammed by a .50 case in the wrong place

Share this post


Link to post
Share on other sites

wi00uMC.png

 

Ob 277.  Note that the fourth road wheel uses a leading swing arm so that the turret basket is not sitting on top of the torsion bar.  It's a similar arrangement to the AMX-30.

 

I have been unable to locate good enough pictures to tell if the example in Kubinka is like this too.  A lot of profile drawings show 277 with normal, all-trailing swing arms.

Share this post


Link to post
Share on other sites

uVAiOVr.png

 

More of 277 and its torsion bars.  It looks to be using IS-7 style bars-in-tube torsion bars.

 

The front idler appears to be attached to the first road wheel, similar to the arrangement in a lot of American tanks, and the first torsion bar appears to be longer.

Share this post


Link to post
Share on other sites

uVAiOVr.png

 

More of 277 and its torsion bars.  It looks to be using IS-7 style bars-in-tube torsion bars.

 

The front idler appears to be attached to the first road wheel, similar to the arrangement in a lot of American tanks, and the first torsion bar appears to be longer.

interesting.  I like how they have the fourth wheel station reversed to make room for the turret ring. 

Share this post


Link to post
Share on other sites

I suspect there would be extra stress on the swingarm, since it's being compressed now when the wheel hits a large bump, but that far back on the tank it shouldn't be a major issue.

Yep.  The AMX30 has leading suspension arms as well, but it didn't seem to cause a problem. 

Share this post


Link to post
Share on other sites

The_Chieftain mentioned that the US did tests with an M26 with the swing arms reversed, and it didn't work very well.

 

I suspect that leading swing arms need to be a bit stronger because most metals are stronger in tension than they are in compression.

Share this post


Link to post
Share on other sites

Not only that, but i think joints between swing arms and torsion bars, swing arms and rollers are subject to very high impact forces when roller hit a big rock or serious bump. This would at least increase wear by noticeable amount.

Share this post


Link to post
Share on other sites

The stresses will also be a function of road wheel diameter.

 

For a given obstacle size, the horizontal vector of force of striking an obstacle will be smaller if the road wheel is larger, up until the obstacle is as high as the axle of the road wheel.

Share this post


Link to post
Share on other sites

The stresses will also be a function of road wheel diameter.

 

For a given obstacle size, the horizontal vector of force of striking an obstacle will be smaller if the road wheel is larger, up until the obstacle is as high as the axle of the road wheel.

 

Peak stress will occur lower than that - you just need the point through which the force acts to be in line with the swingarm (and for a trailing arm, this point is well above the axle). Once you're hitting at the axle level then some of the force will try and flip the arm round to a trailing position, which would be exciting.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Similar Content

    • By LoooSeR
      Hello, my friends and Kharkovites, take a sit and be ready for your brains to start to work - we are going to tell you a terrible secret of how to tell apart Soviet tanks that actually works like GLORIOUS T-80 and The Mighty T-72 from Kharkovites attempt to make a tank - the T-64. Many of capitalists Westerners have hard time understanding what tank is in front of them, even when they know smart words like "Kontakt-5" ERA. Ignoramus westerners!
       
       
         Because you are all were raised in several hundreds years old capitalism system all of you are blind consumer dummies, that need big noisy labels and shiny colorful things to be attached to product X to be sold to your ignorant heads and wallets, thats why we will need to start with basics. BASICS, DA? First - how to identify to which tank "family" particular MBT belongs to - to T-64 tree, or T-72 line, or Superior T-80 development project, vehicles that don't have big APPLE logo on them for you to understand what is in front of you. And how you can do it in your home without access to your local commie tank nerd? 
       
       
         Easy! Use this Putin approved guide "How to tell appart different families of Soviet and Russian tanks from each other using simple and easy to spot external features in 4 steps: a guide for ignorant western journalists and chairborn generals to not suck in their in-depth discussions on the Internet".
       
       
       
      Chapter 1: Where to look, what to see.
       
      T-64 - The Ugly Kharkovite tank that doesn't work 
       
         We will begin with T-64, a Kharkovite attempt to make a tank, which was so successful that Ural started to work on their replacement for T-64 known as T-72. Forget about different models of T-64, let's see what is similar between all of them.
       
       
       

       
       
         
       
       
      T-72 - the Mighty weapon of Workers and Peasants to smash westerners
       
         Unlike tank look-alike, made by Kharkovites mad mans, T-72 is true combat tank to fight with forces of evil like radical moderate barbarians and westerners. Thats why we need to learn how identify it from T-64 and you should remember it's frightening lines!
       

       
       
       
      The GLORIOUS T-80 - a Weapon to Destroy and Conquer bourgeois countries and shatter westerners army
       
         And now we are looking at the Pride of Party and Soviet army, a true tank to spearhead attacks on decadent westerners, a tank that will destroy countries by sucking their military budgets and dispersing their armies in vortex of air, left from high-speed charge by the GLORIOUS T-80!

      The T-80 shooting down jets by hitting them behind the horizont 
          
    • By Collimatrix
      At the end of January, 2018 and after many false starts, the Russian military formally announced the limited adoption of the AEK-971 and AEK-973 rifles.  These rifles feature an unusual counterbalanced breech mechanism which is intended to improve handling, especially during full auto fire.  While exotic outside of Russia, these counter-balanced rifles are not at all new.  In fact, the 2018 adoption of the AEK-971 represents the first success of a rifle concept that has been around for a some time.

      Earliest Origins


      Animated diagram of the AK-107/108
       
      Balanced action recoil systems (BARS) work by accelerating a mass in the opposite direction of the bolt carrier.  The countermass is of similar mass to the bolt carrier and synchronized to move in the opposite direction by a rack and pinion.  This cancels out some, but not all of the impulses associated with self-loading actions.  But more on that later.

      Long before Soviet small arms engineers began experimenting with BARS, a number of production weapons featured synchronized masses moving in opposite directions.  Generally speaking, any stabilization that these actions provided was an incidental benefit.  Rather, these designs were either attempts to get around patents, or very early developments in the history of autoloading weapons when the design best practices had not been standardized yet.  These designs featured a forward-moving gas trap that, of necessity, needed its motion converted into rearward motion by either a lever or rack and pinion.
       

      The French St. Etienne Machine Gun
       

      The Danish Bang rifle
       
      At around the same time, inventors started toying with the idea of using synchronized counter-masses deliberately to cancel out recoil impulses.  The earliest patent for such a design comes from 1908 from obscure firearms designer Ludwig Mertens:


       
      More information on these early developments is in this article on the matter by Max Popenker.
       
      Soviet designers began investigating the BARS concept in earnest in the early 1970s.  This is worth noting; these early BARS rifles were actually trialed against the AK-74.
       

      The AL-7 rifle, a BARS rifle from the early 1970s
       
      The Soviet military chose the more mechanically orthodox AK-74 as a stopgap measure in order to get a small-caliber, high-velocity rifle to the front lines as quickly as possible.  Of course, the thing about stopgap weapons is that they always end up hanging around longer than intended, and forty four years later Russian troops are still equipped with the AK-74.

      A small number of submachine gun prototypes with a BARS-like system were trialed, but not mass-produced.  The gas operated action of a rifle can be balanced with a fairly small synchronizer rack and pinion, but the blowback action of a submachine gun requires a fairly large and massive synchronizer gear or lever.  This is because in a gas operated rifle a second gas piston can be attached to the countermass, thereby unloading the synchronizer gear.

      There are three BARS designs of note from Russia:

      AK-107/AK-108
       


      The AK-107 and AK-108 are BARS rifles in 5.45x39mm and 5.56x45mm respectively.  These rifles are products of the Kalashnikov design bureau and Izmash factory, now Kalashnikov Concern.  Internally they are very similar to an AK, only with the countermass and synchronizer unit situated above the bolt carrier group.


       

      Close up of synchronizer and dual return spring assemblies

      This is configuration is almost identical to the AL-7 design of the early 1970s.  Like the more conventional AK-100 series, the AK-107/AK-108 were offered for export during the late 1990s and early 2000s, but they failed to attract any customers.  The furniture is very similar to the AK-100 series, and indeed the only obvious external difference is the long tube protruding from the gas block and bridging the gap to the front sight.
       
      The AK-107 has re-emerged recently as the Saiga 107, a rifle clearly intended for competitive shooting events like 3-gun.
       

       
      AEK-971

      The rival Kovrov design bureau was only slightly behind the Kalashnikov design bureau in exploring the BARS concept.  Their earliest prototype featuring the system, the SA-006 (also transliterated as CA-006) also dates from the early 1970s.



      Chief designer Sergey Koksharov refined this design into the AEK-971.  The chief refinement of his design over the first-generation balanced action prototypes from the early 1970s is that the countermass sits inside the bolt carrier, rather than being stacked on top of it.  This is a more compact installation of the mechanism, but otherwise accomplishes the same thing.


       

      Moving parts group of the AEK-971

      The early AEK-971 had a triangular metal buttstock and a Kalashnikov-style safety lever on the right side of the rifle.



      In this guise the rifle competed unsuccessfully with Nikonov's AN-94 design in the Abakan competition.  Considering that a relative handful of AN-94s were ever produced, this was perhaps not a terrible loss for the Kovrov design bureau.

      After the end of the Soviet Union, the AEK-971 design was picked up by the Degtyarev factory, itself a division of the state-owned Rostec.



      The Degtyarev factory would unsuccessfully try to make sales of the weapon for the next twenty four years.  In the meantime, they made some small refinements to the rifle.  The Kalashnikov-style safety lever was deleted and replaced with a thumb safety on the left side of the receiver.


       
      Later on the Degtyarev factory caught HK fever, and a very HK-esque sliding metal stock was added in addition to a very HK-esque rear sight.  The thumb safety lever was also made ambidextrous.  The handguard was changed a few times.



      Still, reception to the rifle was lukewarm.  The 2018 announcement that the rifle would be procured in limited numbers alongside more conventional AK rifles is not exactly a coup.  The numbers bought are likely to be very low.  A 5.56mm AEK-972 and 7.62x39mm AEK-973 also exist.  The newest version of the rifle has been referred to as A-545.

      AKB and AKB-1


      AKB-1


      AKB


      AKB, closeup of the receiver

      The AKB and AKB-1 are a pair of painfully obscure designs designed by Viktor Kalashnikov, Mikhail Kalashnikov's son.  The later AKB-1 is the more conservative of the two, while the AKB is quite wild.

      Both rifles use a more or less conventional AK type bolt carrier, but the AKB uses the barrel as the countermass.  That's right; the entire barrel shoots forward while the bolt carrier moves back!  This unusual arrangement also allowed for an extremely high cyclic rate of fire; 2000RPM.  Later on a burst limiter and rate of fire limiter were added.  The rifle would fire at the full 2000 RPM for two round bursts, but a mere 1000 RPM for full auto.

      The AKB-1 was a far more conventional design, but it still had a BARS.  In this design the countermass was nested inside the main bolt carrier, similar to the AEK-971.

      Not a great deal of information is available about these rifles, but @Hrachya H wrote an article on them which can be read here.
       
       
    • By LostCosmonaut
      Something I haven't seen discussed on this site before; Soviet/Russian efforts to domesticate foxes by breeding for domesticated behavior. Article in Scientific American here; https://blogs.scientificamerican.com/guest-blog/mans-new-best-friend-a-forgotten-russian-experiment-in-fox-domestication/
       
      Interesting that there were physical changes correlated with the behavioral changes the Russians bred for.

       
      Buy one for only $7,000! https://domesticatedsilverfox.weebly.com/aquiring-a-tame-fox.html
       

      (not entirely unlike a dog I guess)
       
       
      It seems like a pretty cool idea to drunk me, though I don't have a spare 7,000 dollars laying around (thanks student loans!). Also, I don't think my cat would approve.
       
×