A question regarding Pak's
A question regarding Pak's
Whenever I see the different Pak guns or guns mounted in tanks, every version has a L/?? and the question marks mean the different numbers present. What does that number mean? Such as for example 20mm KwK 30 L/55, 50mm KwK 39 L/60, 75mm PaK 40 L/46 etc.
Thanks,
Besian
Thanks,
Besian
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Re: A question regarding Pak's
Hi!Korbius wrote:Whenever I see the different Pak guns or guns mounted in tanks, every version has a L/?? and the question marks mean the different numbers present. What does that number mean? Such as for example 20mm KwK 30 L/55, 50mm KwK 39 L/60, 75mm PaK 40 L/46 etc.
Thanks,
Besian
As Panzermeyer wrote the "L" means the lenght of the barrel (compared to the caliber).
20mm KwK30 L/55 = 20mm x 55 = 1100mm
50mm KwK39 L/60 = 50mm x 60 = 3000mm
75mm PaK 40 L/46 = 75mm x 46 = 3450mm
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Well indeed, with a longer barrel the velocity of the shell will be increased and also the accuracy.
This is very important for AP shells not especially for HE or HEAT rounds. An AP rounds uses the velocity, the kinetical energy to penetrate its taget, especially APCR shells.
That's why for a 50 mm gun on a PzIII for exemple, the short barrel will not achieve easy kills against ennemy tanks but the long barrel version had better chances to destroy a tank and at longer range.
just my 2 cents.
David
This is very important for AP shells not especially for HE or HEAT rounds. An AP rounds uses the velocity, the kinetical energy to penetrate its taget, especially APCR shells.
That's why for a 50 mm gun on a PzIII for exemple, the short barrel will not achieve easy kills against ennemy tanks but the long barrel version had better chances to destroy a tank and at longer range.
just my 2 cents.
David
L/??
The longer the barrel the more of charge to launch the shot out of the gun.
Thus a longer gun barrel a larger breech to contain the larger explosion of the charge, thus a heavier gun.
When measuring gun barrels by the above equations remember that some countries would include the length of the breech also.
admfisher
Thus a longer gun barrel a larger breech to contain the larger explosion of the charge, thus a heavier gun.
When measuring gun barrels by the above equations remember that some countries would include the length of the breech also.
admfisher
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redbaron
Hi Redbaron
The HE, SAP, and such did not need the high muzzle velocity, thus the field guns and howitzers usually weighed much less.
We have a great visual here where I live. There is a 17 pdr, and a 25 pdr at the park.
The 25 pdr has the bigger size of barrel, the but the 17 pdr almost drawfs the 25 pdr.
It is really something to look at, the 17 pdr which was an excellant weapon has a massive breech compared to the 25 pdr. The 25 pdr could fit into the 17 pdr's position if it were in a emplacement. Where the 17 pdr would never even come close to fitting.
The guns are totally different in length, hight, weight and every other catagory.
With a field gun the charge is much smaller thus the less recoil thus the smallers size.
If you want I can send you a pic of each to compare.
admfisher
The HE, SAP, and such did not need the high muzzle velocity, thus the field guns and howitzers usually weighed much less.
We have a great visual here where I live. There is a 17 pdr, and a 25 pdr at the park.
The 25 pdr has the bigger size of barrel, the but the 17 pdr almost drawfs the 25 pdr.
It is really something to look at, the 17 pdr which was an excellant weapon has a massive breech compared to the 25 pdr. The 25 pdr could fit into the 17 pdr's position if it were in a emplacement. Where the 17 pdr would never even come close to fitting.
The guns are totally different in length, hight, weight and every other catagory.
With a field gun the charge is much smaller thus the less recoil thus the smallers size.
If you want I can send you a pic of each to compare.
admfisher
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It mostly depends on the caliber and how much powder there is in the cartrige. Longer barrels allow more propellant burnt and so a faster mooving bullet, also helps on the accuracy because it guides the project for a longer way through the "riffling" (when there is one) of the gun. But too long barrels are bad because when the whole propellant burns there is no more things to push the bullet on, so the bullet just looses mechanical energy and as so speed.redbaron1908 wrote:So does this mean if the lenght of the barrel is longer that the gun is more powerful or not really?