06-03-2016, 08:05 AM | #41 | |
Join Date: Jan 2010
Location: Brighton
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Re: WWII: 40mm Autocannon VS tanks?
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Roll on Vehicle design! Actually a system like the armour articles would work, DR per inch, WM, adjustment mods for different slopes (as opposed to different construction types) etc., etc Surface area would be more complicated though, (and would have several factors including slopping) |
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06-03-2016, 08:49 AM | #42 | |
Join Date: Oct 2010
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Re: WWII: 40mm Autocannon VS tanks?
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Apparently the Hungarians had their own AP shell for the Bofors gun with penetration which seems to be similar to the 2 pdr. However by the time it was being used on the Eastern Front it was very underpowered vs Russian medium tanks. |
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06-03-2016, 11:51 AM | #43 | |
Join Date: Jan 2010
Location: Brighton
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Re: WWII: 40mm Autocannon VS tanks?
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Another factor is a 40mm bofors gun and carriage is almost 6,000lbs. Now some of which is due to it being an anti-air platform, but some of it is to do with it's to do with the firing mechanism that can accommodate a much faster Rof (6x that of the 2lb cannon) If you look at similar calibre dedicated anti tank guns at the time, that are far smaller and lighter*. A big part of being an anti tank gun is being quick and easy to move and hide. (Especially if you're a 40mm gun who has to rely in short range shot placement on weak spots) Don't get me wrong I'm sure Bofors guns were used in anti tank roles when the need arose. But ultimately to make it a dedicated anti tank gun you'd end up changing it so much you might as well just use the 2lb gun anyway. Anti tank guns of such calibre were obsolete pretty quickly in all but the pacific theatre, and that was a theatre where you wouldn't fancy dragging a heavy anti tank gun around in (and as above you won't need to anyway). In Europe / North Africa if you going to move a heavy anti tank gun around your going to go with a 17lb gun which can tackle most tanks you're likely to meet. *some comparisons the British 2lb is heavy and big in this class at 1795 lbs, the German Pak 37 was 990lbs, the US M2 is 912lbs. Last edited by Tomsdad; 06-03-2016 at 12:29 PM. |
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06-03-2016, 12:52 PM | #44 | |
Night Watchman
Join Date: Oct 2010
Location: Cambridge, UK
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Re: WWII: 40mm Autocannon VS tanks?
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__________________
The Path of Cunning. Indexes: DFRPG Characters, Advantage of the Week, Disadvantage of the Week, Skill of the Week, Techniques. |
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06-03-2016, 02:31 PM | #45 |
Join Date: Jul 2006
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Re: WWII: 40mm Autocannon VS tanks?
IIRC it also had a beast of a recoil - that being why British tank designers stepped back down to the 77mm gun. The 17lbr's first outing was the "Pheasant" project - with the gun mounted on a 25lbr howitzer carriage. The recoil, apparently, was excessive and tended to break the carriage.
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06-03-2016, 07:58 PM | #46 | |
Join Date: Jul 2008
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Re: WWII: 40mm Autocannon VS tanks?
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I don't know any 3e, so there is no chance that I am talking about 3e rules by accident. |
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06-04-2016, 01:40 AM | #47 | ||
Join Date: Jan 2010
Location: Brighton
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Re: WWII: 40mm Autocannon VS tanks?
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In arenas where you don't need such a powerful gun you can avoid lugging a big cumbersome gun around and still have the power of the 40mm with a 2lb gun and a lot less weight The problem with the 6lb gun is that it was pretty borderline ineffective even when it was introduced, and it only got worse from there. But yes still a good step up from the 2lb for not a lot more weight (the British 2lb was very heavy for it's class though) But yeah the 17lb is a big heavy gun, but as you say only slightly heavier then the a 40mm Bofors anti air platform. So even if you can shave some weight and size of such platform for dedicated anti-tank use, your still going to be compromising. The problem is you compromising in one direction (increased weight etc) but not getting a pay off in the other, a 40mm is limited in effectiveness vs. thicker armour. Now to be fair you use different guns in different sets up in different ways here. A 40mm bofors anti air gun is firing at 120 rpm, because it's job is to chuck as much stuff at distant fleeting targets as possible, were even a glancing HE hit will possibly do the job. So you have all the infrastructure to enable fast firing and a whole load of ammunition to burn though. Anti tank fire is pretty much the opposite, that's all about about either you out-ranging the tank (which you won't be doing with a 40mm unless it's a very early tank), or taking a a few aimed shots at the right time before you are found and blown to pieces. Quote:
True, but it's the latter I think that's the issue, as a lot of listing don't rate the value of such material by standard that can be used in GURPS. Although more recent tanks with more exotic armours do occasionally give an equivalent in thickness vs. different damage Ke/HEAT I've noticed i.e RHAe) Last edited by Tomsdad; 06-04-2016 at 01:44 AM. |
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06-04-2016, 02:30 AM | #48 |
Join Date: Jul 2008
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Re: WWII: 40mm Autocannon VS tanks?
I thought the 6-pounder was very respectable...as an anti-tank gun. Where it came up short was as an infantry support gun, because its HE was no match for what you could get out of a 75mm gun.
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I don't know any 3e, so there is no chance that I am talking about 3e rules by accident. |
06-04-2016, 04:42 AM | #49 | |
Join Date: Jan 2010
Location: Brighton
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Re: WWII: 40mm Autocannon VS tanks?
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Even when firing AP it didn't fire it at particularly high velocity, so it had to be pretty close to beat say a panzer 4's front armour, and that causes problem for using the gun in combat for several reasons. It absolutely rocked the first half of the war against P1-3 and early P4's, but ended up effectively out ranged the later it got. Look at the difference in penetration ability between the 6lb QF and the german 75mm, Yes the 6lb can just about get through the front of P4 but it's close (and that's at 100m), but look at the other gun's performance at similar and longer ranges. Now yes the German gun is 75mm and more powerful etc, etc but it's only 25% heavier. And yeah you are right about the HE being a bit lacklustre out of a smaller calibre. (but then that what your 25lb howitzers are for I guess) Last edited by Tomsdad; 06-04-2016 at 10:40 AM. Reason: took the soviet gun out as the pentration table is likley wonky |
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Tags |
40mm, aa gun, autocannon, spalling, wwii |
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