Lord_James

T-84 Oplot obr. 1999. Allegedly only five are operational in the whole Ukraine. 

Second best tank on the planet after Oplot BM.

105mm IWS

This should be PT19, assuming all photos show the same tank. It has the license number "Y-04 002" and was the Leopard 2AV prototype sent to the United States for evaluation in 1976.
PT19 featured the Hughes-designed FCS and could be configured to be used with the 105 mm L7A3 and the Rh 120 guns.
 
The Leopard 2AV PT20 was only fitted with the 105 mm L7 gun, but featured the EMES 13 sight and an FCS made by AEG. The EMES 13 allows to identify it from most angles.

 
PT20 also had the license plate "Y-04 003".
 
Aside of the two prototypes PT19 and PT20, West-Germany also created the turret T21 as part of the Leopard 2AV project, which was later fitted to the PT20 hull for trials, featuring the 120 mm Rh 120 gun and the Hughes FCS

That's completely wrong, sorry. 

Note Shrek on UFP. Also, it fired ATGMs. Would be so funny if this thing will end up being used as AT vehicle more than it's intended role.

Belarus JDB made AK-74M into a *dramatic pause* bullpup *thunder strikes in the background*

Note jihaded grip-less GP-25 on that abomination. Charging handles looks like is now on top, under rail-handle. Front iron sight post was chopped away. And that small slip over safety/selector is not closed by some sort of plastic.

I wouldn’t think it would have been over in 72 hours, even without donations to Ukraine. The mad max “drive fast” strategy the Russian army was using was bound to stall out quickly, taking into account how little they protected their logistics at that point in the war. It would be much more favorable on the Russians side if there was no external assistance, but I don’t think that Ukraine would have been steam rolled as implied without the military aid. I’m just an idiot on the internet though, but willing to be proven wrong on the appropriate thread. 

The interface between the sliding wedge of the breech block and the breech ring is what is improved.



As you can see, on the M256 the shoulder in the breech ring that the sliding wedge rests against is a single element that's more or less a square corner (albeit radiused).  In the Rheinmetall 130mm weapon you can see that the interface between the sliding wedge and the breech ring has two layers, and that it's sort of a rolling teardrop shape with a much more generous radius.  It's not unlike what the US was looking at with the XM360:



It's been known for a very long time that this sort of design of sliding wedge is stronger, but it's traditionally been considered too much of a pain in the ass to manufacture to be worth it.  Perhaps computer stress modelling and improved manufacturing technology have changed that.

By reducing stress I mean it reduces stress in the metal of the breech mechanism.  The stress at any given point in the breech ring and the breech block has to be lower than the yield strength of whatever uber-steel it's made out of so the gun isn't permanently deforming itself with each shot.  Ideally the stress should be quite a bit lower in order that the mechanism has good fatigue life.  When the original 120mm Smoothbore was designed (late 70s) I doubt that full computational finite element analysis was possible; the computers were too pathetically weak back then.  The stress analysis was probably done with some computer modelling, but also good old fashioned rules of thumb and photoelastic stress simulations:



It is possible to modulate pressure within the tube with propellant design, but to what end?  Yes, pressure in the breech is what causes the stress on the locking elements.  Pressure in the breech is also what makes the projectile go downrange.

Keeping the peak recoil force within reasonable bounds is important as well, so I suspect that the recoil system on the 130mm will need to permit the gun to travel further than the system in current 120mm armed vehicles.  However, increasing the travel of the gun during recoil doesn't really change the width of the gun system that much.  Look at how cramped the gunner's position is in an Abrams, which is supposed to be one of the MBTs with more generous elbow room:



That position, by all accounts, kind of sucks, but if the gun gets even a few centimeters wider it's going to suck way more.

Their overall design rationale reminds me a lot of the conceptual studies in British tank guns that led up to the 120mm L11.  Lower breech pressure means that the breech, ceteris paribus can be narrower and thus take up less room in the turret because the breech ring and barrel don't need to be as thick.  This also makes stabilization a little easier because there's less steel for the stabilizer to have to wrestle with.  Lower peak pressure also makes life a little easier for the ammunition designers because the interface between the sabot and the dart is experiencing less peak force.

The problem with this line of thinking is that it's really hard to get the raw performance.  Kinetic energy of the projectile is the integral of the pressure at the base of the projectile swept along the volume of the bore.  For a given mass of propellant, higher pressure guns have better thermodynamic utilization of the propellant.  In small arms, higher peak pressure also gives more consistent internal ballistics and thus accuracy, but I am not sure if this is a major factor in tank guns.

The Rheinmetall 130mm has the same cartridge base dimensions as the 120mm:



So the increase in breech thrust against the breech block and the stress in the firing chamber and breech ring should only be greater by (approximately) the percentage increase in pressure.  On top of that, the breech designs Rheinmetall has shown have a more sophisticated wedge design that existing 120mm guns which should provide better distribution of the firing loads and thus lower peak stress:



There may also have been metallurgical improvements in gun breech materials in the... what, half century since the 120mm smoothbore was invented?

So the width increase of the 130mm vs. the 120mm may be very small.  The gun will probably need greater recoil travel and may need to be mounted further back in the turret, so it is not space-neutral or anything like that.  However, with the current manned tank turret design of placing the gunner, gun, and commander abreast (or loader, gun and gunner in designs with a flesh loader), the width of the gun breech is dividing the turret right down the center and determines to a large degree how much elbow room is left for the crew for a given turret ring diameter.

So, given that the Rheinmetall design is more mature, more powerful, and shouldn't be too much wider than the existing 120mm smoothbore, the advantages the Ascalon offers seem poor by comparison.

No.  The stabilizing lift force provided by the fins is a function of angle of attack times fin area times airspeed squared.  The overturning moment acting on the rod is a function of the moment arm between the aero center and center of gravity times airspeed squared.  The stabilizing moment provided by the fins is a function of their stabilizing lift force times the moment arm between the fins and the center of gravity.  Thus, as long rods have gotten longer and longer, these competing effects have more or less canceled out and the fins have stayed about the same size.
 


Because the stabilizing force provided by the fins is a function of airspeed squared and the overturning force is also a function of airspeed squared, a long rod penetrator that's stable at one airspeed is stable at any airspeed.  The only exception is the transonic where lift coefficients and aero centers can jump around, but that's pretty much academic because an APFSDS long rod going transonic velocities isn't going to be killing very much.
 

Replacement of the rubber pads on the tracks of an Au F1 SPG, followed by the reinstallation of said track :
 
 

ADATS, good pic of bradley spaced side skirts 

https://spacenews.com/diu-selects-nuclear-powered-spacecraft-designs-for-2027-demonstrations/
 
"The Defense Innovation Unit announced May 17 it selected Ultra Safe Nuclear Corp. and Avalanche to develop small nuclear-powered spacecraft for in-space demonstrations planned for 2027."
 
  "Avalanche Energy has developed a device called an “Orbitron,” which utilizes electrostatic fields to trap fusion ions in conjunction with a magnetron electron confinement scheme to overcome charge density limits. The resulting fusion burn then produces the energetic particles that generate either heat or electricity, which can power a high-efficiency propulsion system. Compared to other fusion concepts, Orbitron devices are promising for space applications as they may be scaled down in size and enable their use as both a propulsion and power source."  

The vehicle is Patriot II from Excalibur Army using Tatra chassis. Here you can find more about the vehicle. 
https://patriot.excaliburarmy.cz/
 
EDIT: I can see that it's also bing advertised as Husar made by Polish Stalowa Wola. Anyway it's the same vehicle probably developed in joint venture. 

Searching the USAHEC's digital archive and found a few different docs on the XK1's development. And along with that some pictures of the XK1 at a very high resolution. Both pictures are of PV-2.
 

This is not a DM33 - length, weight, shape and muzzle velocity do not match.

I wasn't aware that the KE-T round actually had a longer penetrator and higher muzzle velocity than the M829 APFSDS.

@Laviduce right now 
 

@Laviduce right now 
 

In addition to that:



 

It appears to be a version of the Lynx 120's turret.
 

Rheinmetall teaser image for next month's Eurosatory. Has that turret been seen before?