Why don't tanks have 152mm smoothbore guns?

Because they don't need them.

>>32177285
151 then?

>>32177248
Weight

America does not have the technological know how for smoothbore guns. They will be forced to copy Chinese tank designs but their main problem is they do not have good munitions for a smoothbore gun.

>>32177421
substantiate your claim.

>>32177421
Babby's first shitpost

>>32177248
yet

>>32177421
are you fucking retarded? you sound like a fucking retard.
120 on a2 is smoothbore for one and it's actually easier to make than rifled barrels god damnit.

t30 prototype had a fully functional 155mm gun they decided it was both overkill both too slow to reload for an mbt and had low ammo capacity also. so it was never put to production.

>>32177248
Because the 120 on the Abrams can already pen practically anything. If you need more firepower, it's time to call in a missile strike.

>>32177248
Weight and the required reduction in ammo capacity. Also, a gun that large offers no practical advantage over existing models.

It`s better to improve ammunition than to give tanks a "bigger" sabot. The only 152mm gun that COULD be in service is the one designed for the Armata, and the engineers agreed that better ammo for the 125 would be more beneficial.

>>32177248

the gun and ammunition is extremely large, and there is no real reason to use them. 120mm works fine.

>>32177883
well it would actually significantly
>much greater HE capability
>heat round penetration is correlated to round diameter
>even longer and heavier perpetrators could be accelerated from a larger diameter barrel to the same velocity with the same pressure characteristics
>150mm shillelagh (or more modern variant) actually truly relevant atgm launch capability

jesus shit would be so cash some tankers would cream their pants.

>9mm vs .45acp
>tank version

Heavy tank bros are almost as bad as battleshit bros

>>32177927
well not really, it you had an ammo that would put out the .45 with the same velocity (400+ m/s) as a 9mm then it would be a similar dilemma.

>>32177933

Next this Russian shill will be telling us "its the CURRENT YEAR you don't need carriers"

>>32177248
Tanks are designed by compromise. Larger guns add more weight and require a larger turret to house the weapon and ammunition. That means the bigger turret means more armor which adds even more weight. A larger diameter gun also has larger shells so going up from a 120 mil to a 150 mil means you have to either 1) carry less ammo or 2) make the turret even bigger and again that means more armor and structure and more weight. Then because your carrying more weight you have to either get a new engine to be able to maintain the speed and maneuverability of the vehicle or use the same engine and make it slower to move and turn. This usually means a bigger engine and more weight that you have to factor into the final decision on what engine to use. Bigger engine means it will probably require more fuel for the needed level of efficiency again more weight. Now you have to rework the suspension to handle all that added weight and you might even have to redesign the hull in order to account for a new engine and expanded fuel tanks.

Then you have to really evaluate the new gun is it really needed to get the performance we want or can we design a new shell for an existing weapons system. The latter is why most tanks have smaller than 150 mils. At one time they planned on equipping tanks with 150s but new designs for tank shells turned out to give the same level of armor perforation. So there was no need to use a different weapon and you didn't have to redesign around the added weight.

>>32177997
if you think you don't need to redesign or at least reevaluate everything for newer more powerful ammo, you are insane. the higher velocity requires higher pressure and or longer barrel more barrel with more material which needs to be balanced larger pressure comes from more propellant usually so bigger shells overall, more weight and space already required, to counterbalance the heavier gun and more robust stabilizer you need a longer turret and it will produce different shockwaves when fired too, the forces that act on the turret the ring and superstructure change a lot maybe you need to reinforce or replace a lot of other shit.

it's almost like a new tank in the and anyhow.

>>32178065
well insane is not the right work delusional maybe

>>32177920
If the 120mm can already assblast anything from 2 miles away, then there is no real improvement in usability.

A 152mm is better that a 120mm at killing tanks, but we don't need better tank killing right now. When the need shows up, we can put them on then.

>>32178065
>>32178078
Can you use some fucking punctuation please?

A newer, more powerful ammo is made within the constraints of the current system that uses it.

A military is not going to completely remake a gun system and tank unless the ammo cannot work within existing confines, but still offers a massive improvement over the existing ammo.

>>32177285
>need

SHALL

>>32177248

120/125mm guns are sufficient for penetrating any current tank.

>>32177954
We do though, it's called the .44 Special, and there is no debate about which is the better carry piece because of size, weight, and capacity concerns.

What are the improvements of smoothbore?

>>32178202
yeah .44 is so much better it's painful

File: 862649.jpg (235KB, 880x660px) Image search: [Google]

235KB, 880x660px

>>32178202
>.44 special

What world do you live in where that's what you go to instead of .45 Super, a round much more compatible with a decent amount of already available, good semi auto handguns, like the USP?

In this case as long as you don't have tiny hands, and either have money or willingness to handload, it sure as fuck is better than 9x19mm.

>>32178145
NOT

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155KB, 1091x446px

>>32177248
already been done before

>>32177248
Think about it like this.

The point of the tanks cannon for fighting other tanks is to pierce their armor and kill the crew/Disable the tank.

Making the cannon bigger simply means your throwing a bigger she'll at it that does not change a lot rather then what you can put in the shell is much more.

So think of it like you having a low velocity gun but giving a bigger sized shelled to pierce armor the gun already couldn't pierce.

On the other hand you could increase the velocity of the gun or make ammo of a specific type meant to break through said armor.

Example if instead of sizing up you took the gun and made it have more power behind the shot by increasing a number of other factors. This means it flies faster, trajectory could be flatter, higher velocity means an easier time of penetration of the shell isint shit.

>>32178490
The kineticpenetrator isnt the only method for piercing armor faggot

>>32178238

Better than rifled for APFSDS and HEAT rounds.

The reason to have 155mm tank guns is to enable them to fire tactical nukes

>>32179032

Undisputed

>>32178463
What object number is that?

>>32178463
How many shells could this tank hold, 2?

>>32178195
arguably situational
also you could make a 76mm gun that could pen all modern tanks yet we still use bigger guns mainly for their ability to be more versatile with various rounds against various targets and also to do tons more damage.

>>32177862

On the contrary, the gun of the Abrams can't even reliably penetrate its own armor.

>>32179915
It wouldn't surprise me if they had specs for a shell that could pen it on file somewhere deep inside DARPA's vault.

Abrams has the heaviest armor of any MBT out there.

>>32179255
says right there, 292

>>32177421
>anyone copying china

wouldn't that be like photocopying a shitty photocopy?

>>32177248
Bigger gun =
>Less ammo
>Bigger turret
>Greater weight
>Lower speed
>Slower fire
The 120 smoothbore does what is necessary, and if that's all you need than that's all you'll want to use. Overkill is exorbitantly wasteful, especially when your talking about war machines which are already expensive enough as-is. You want exactly enough gun to get whatever job you need done, no more and no less.

Rheinmentall is working on a 130mm gun for 2025/2030, presumably because they are assuming that the standards for armor will improve and thus a bigger gun will eventually be necessary to reliably penetrate that future armor. Improvements in armor technology are one factor which would justify the addition of a larger gun, but guns will increase in size only as much as they need to in order to continue reliably penetrating armor. As far as I know there is no justification for a 155mm gun, there's nothing heavily armored enough to be worth the reduced ammo capacity.