Project Reality Forums

NikovK wrote:I was always under the assumption that tracers didn't burn evenly, so while the bullet spins along its flightpath the glowing gas is slung off to one side, making a corkscrew effect which looks like a side-to-side wobble at an angle.

HEAT rounds penetrate by concentrating energy on one point. Spinning would slew the plasma out to the sides of the axis of spin.

I think you overestimate the speed of spin vs. the speed at which the 'jet' forms ...

Well, when you're trying to put ten pounds of HE on dime, little bits matter. Its not my opinion, its a source I picked up.

"Mats Persson" <[email protected]> wrote in message
news:[email protected]...
> Karl Vorwerk wrote:
> >
> > This made me wonder. What is the spin rate (RPM) of the average rifled
tank
> > round? More interestingly how fast must it rotate to disperse the shaped
> > charges jet?
>
> spin = (muzzle velocity)/(length of one twist) [ /s]
>
> For an S-tank firing HE-shells that makes
>
> 680 [m/s] / (18*0.105) [m] = 360 [ /s] = 21600 [rpm]
>
>
> The Swedish Army noted that the 84 mm m/48 Carl Gustaf RCL had pour
> armour penetration using spin stabilized HEAT-ammunition. In 1956 they
> went to non-rotating HEAT which increased the performance.
>
> With a muzzle velocity of approximately 300 m/s and one twist in 3.268
> metres the grenade from a m/48 has a spin of 300/3.268=90 [ /s] = 5400
> [rpm]
>
> Which is notably less than the spin of a shell from a tank-gun.
>

Regarding rifled vrs smoothbore...

Eugene Griessel wrote:
>
> "Zonie! remove the excitation mark and 1 M for real email address"
> <[email protected]> wrote:
>
> >The M1A1 Abrams converted to a smooth bore from a smaller rifled bore.
> >
> >What advantages does a smooth bore give you?
>
> The main ammunition for anti-tank work is an armour piercing fin
> stabilised discarding sabot round. The so-called "long-rod"
> penetrator. While spinning a shell helps to stabilise it it does
> subject the round to precession. This means the point tends to wander
> in a small circle. This is less than desirable when you want to punch
> a hole through armour by brute force. You want a "square" hit so that
> all the force is concentrated on one spot.

Also, with a need for higher velocities to penetrate armour the fin
stabilized long-rod can be accelerated to higher velocities from a
smooth bore than a rifled gun.

The gas seal on a rifled round has to be metal-on-metal contact between
the round and the barrel this has a high friction co-efficient -
limiting acceleration of the rifled round - possibly why a longer barrel
allows higher velocity (but it has an upper limit where gas pressure is
no longer able to accelerate against the friction).

On a fin-stabilized round the gas seal can be plastic etc (any suitable
low friction material). There are no edges inside the barrel to inhibit
acceleration (rifling). So more energy is expended accelerating the
round (than equivalent rifled round) allowing higher velocities from a
shorter barrel.

Advantages (IMO):
1) Cheaper barrels (no rifling)
2) Longer lasting barrels (no rifling to wear)
3) Shorter barrels (see 1 above)
4) Higher projectile velocities - better armour penetration (from
shorter barrels).
5) etc
</XMP>

For more information go here...

http://www.ciar.org/ttk/mbt/

Put it this way. If CHARM and rifled barrels are so crappy compared to smoothbore... how could it destroy another Challenger 2 in one hit? Which is the most heavily armoured tank in the NATO aresenal? They're more than capable of destroying heavy armour in one shot so what's the problem? And like I've said several times before, they're just cheaper and easier to make (smoothmore). We don't tend to care for cutting corners if it means we get better equipment.

You wouldn't be blowing up NATO tanks. You'd be blowing up Kontakt-5 armored T-90s if anything. That little bit of orbit on a tungsten penetrator and the lower muzzle velocity from a rifled barrel could well make all the difference. A marginally higher velocity DU penetrator rod without a point orbit may be enough extra for the kill.

Mad Max wrote:Put it this way. If CHARM and rifled barrels are so crappy compared to smoothbore... how could it destroy another Challenger 2 in one hit? Which is the most heavily armoured tank in the NATO aresenal? They're more than capable of destroying heavy armour in one shot so what's the problem? And like I've said several times before, they're just cheaper and easier to make (smoothmore). We don't tend to care for cutting corners if it means we get better equipment.

Are there any sources that mention where on the Challenger it was hit?

NikovK wrote:
> spin = (muzzle velocity)/(length of one twist) [ /s]
>
> For an S-tank firing HE-shells that makes
>
> 680 [m/s] / (18*0.105) [m] = 360 [ /s] = 21600 [rpm].

Where do you get the (18*0.105) bit from?

Also, isn't there some 'slippage', i.e. the round does not spin as fast as the rifling would suggest because of inertia?

BTW I don't disbelieve what you're saying, I'm just interested ...

NikovK wrote:You wouldn't be blowing up NATO tanks. You'd be blowing up Kontakt-5 armored T-90s if anything.

Are they really better armoured than the Dorchester armour of a Challenger II?

Check the source. That's not my page, sorry. Regarding Dorchester/Kontakt-5, you'd be better off asking a philosopher.

I really doubt Rheinmetall is "cutting corners" on its 120mm smoothbores, just like I really doubt the USA is cutting corners by buying cheap weapons for a very expensive tank.

I believe it's something like 5kph slower than the Abrams, but then they do have jet turbine engines running on aviation fuel whilst the CR2 uses diesel most of the time).

What do you mean by challenger 2 tanks run on diesel most of the time?

Xeon wrote:What do you mean by challenger 2 tanks run on diesel most of the time?

I think it means that the tank uses diesel fuel to power its engine less than 100% but greater than 50% of the total time the tank is running.

Pretty confusing, I know ...

Wo ladies! Less bitchin' more praisin'! Excellent job on the Warrior IFV guys, can't wait to go for a spin in it. Someday .

whatever happened to the Warrior - PRM seemed to have a complete model this time last year

$kelet0r wrote:whatever happened to the Warrior - PRM seemed to have a complete model this time last year

The full works are coming in to this mod in v1.0. That is still some time off when you consider we are hoping to release v0.41 before x-mas.

We will update you with new stuff when its ready.

I expect version 1 will come quicker than .1 -. 4 did (or greater change to come), especially since they are a part of Black Sand (see here ). They will be able to utilize work from the other modding teams, reducing their work on useless models that are equivalent or superior to what they can create, well maybe not superior, but equivalent . I wish that more modding teams will join BS.

The TJ wrote:I expect version 1 will come quicker than .1 -. 4 did (or greater change to come), especially since they are a part of Black Sand (see here ). They will be able to utilize work from the other modding teams, reducing their work on useless models that are equivalent or superior to what they can create, well maybe not superior, but equivalent . I wish that more modding teams will join BS.

We where a brand new mod team when we started PR. We have released mini-mods on the way so that we can exspand our player base etc which has worked very well. This has made our work load more than it would be if we where just going to make everything to v1 like the FH2 team or POE2 team have done.

Both the FH2 and POE2 team where not brand new mod teams, hell FH2 has been huge since BF1942 and had loads of exsperiance under there belt. The thing is, only POE2 have released there full version, which they are still working on top of, but has FH2? No. BF2 modding takes a very, very long time. Much longer than BF1942 etc.

You might expect us to have done v1 by now, but we have acturly been pretty speedy with our work flow considering everything.

'[R-DEV wrote:Rhino']The full works are coming in to this mod in v1.0. That is still some time off when you consider we are hoping to release v0.41 before x-mas.

We will update you with new stuff when its ready.

BUMP.


ROFL MAO....

So thats what some said "when Devs said, GB is going to be in v1.0"...lol

Interesting, I thought, Warrior was modeled recently to be included in 0.6, not at the start of 0.1..oh well..

bump was a bit pointless...

Outlawz wrote:BUMP.


ROFL MAO....

So thats what some said "when Devs said, GB is going to be in v1.0"...lol

Interesting, I thought, Warrior was modeled recently to be included in 0.6, not at the start of 0.1..oh well..

design plan has changed a lot since that post...

Warrior was in fact modeled way before BF2 was out, along with most of our other models for GB apart from the C2 and landy which where only made recently.

I read this thread then the thread by gunwing and it's just amazing how the same sounding voices are still here whining and complaining when the Warrior is out and kicks *** as well as so many other weapons systems.
v1.0 is going to be groundbreaking uber doober awesome.