Guest jaja Posted January 1, 2001 Share Posted January 1, 2001 I've heard the US has only one 90mm gun. Yet the Pershing and Jackson have different penetrations. Some say this is due to different types of ammo, but then why do the Pershings have all the good ammo? Also, both guns look different in Combat Mission. Can someone clarify all this? Link to comment Share on other sites More sharing options...
Guest Rob/1 Posted January 1, 2001 Share Posted January 1, 2001 The Pershing and the Jackson have diffrent blasts sranths thats why there penetrations are differant Link to comment Share on other sites More sharing options...
Colin Posted January 2, 2001 Share Posted January 2, 2001 Something about Rob/1's post's always make me wince. ------------------ And if we abandon any platform, I can assure you it will not be the Macintosh. -Steve My website! A major source of Wild Bill scenarios! Link to comment Share on other sites More sharing options...
rexford Posted January 2, 2001 Share Posted January 2, 2001 90mm gun comes in two muzzle velocities, which are related to barrel length. One at 2650 fps, other at 2800 fps. Different penetration stats for each vs. homogeneous rolled armor: 90mm APCBC at 2650 fps 157mm at 100m 148mm at 500m 136mm at 1000m 90mm APCBC at 2800 fps 173mm at 100m 162mm at 500m 150mm at 1000m Increased muzzle velocity increases accuracy, as general rule. Source is TM 9-1907 Link to comment Share on other sites More sharing options...
rexford Posted January 2, 2001 Share Posted January 2, 2001 Tank hull and turret ring size limit the gun that can be carried, due to recoil forces. M36 uses Sherman hull which was designed for 76mm gun, Pershing has hull specially designed to carry longer 90mm gun. Rounds for longer gun might have more powder charge and heavier ammo going into gun, but 90mm APCBC projectile came in one size and weight. Panther round that went into gun was longer and heavier than PzKpfw IVH, but both used 15# projectile. My guess is that M36 turret ring and hull limited barrel length and muzzle velocity. If Pershing and M36 used same cartridge and powder charge, Pershing would still have more recoil forces and higher velocity. Link to comment Share on other sites More sharing options...
Guest Rob/1 Posted January 2, 2001 Share Posted January 2, 2001 <BLOCKQUOTE>quote:</font><HR>Originally posted by Colin: Something about Rob/1's post's always make me wince. <HR></BLOCKQUOTE> why? What is everyones problem! Its like I have done anthing to you. Well if I have sorry. Can we get back to CM now. Link to comment Share on other sites More sharing options...
Phoenix Posted January 2, 2001 Share Posted January 2, 2001 <BLOCKQUOTE>quote:</font><HR>Originally posted by Rob/1: why? What is everyones problem! Its like I have done anthing to you. <HR></BLOCKQUOTE> Why? Haven't figured it out by now? Rob, no one can figure out what the hell you are writing 90% of the time. [This message has been edited by Phoenix (edited 01-01-2001).] Link to comment Share on other sites More sharing options...
Guest Madmatt Posted January 2, 2001 Share Posted January 2, 2001 Rob, we all know you are trying to help but you HAVE to pay more attention to what you you write and try and use the spellchecking option that is available to you. There is also a Grammar tool that might prove helpful to you. If you don't, then you have to be prepared to accept some criticism of what you write as it is very hard to understand most times. Madmatt Link to comment Share on other sites More sharing options...
Colin Posted January 2, 2001 Share Posted January 2, 2001 <BLOCKQUOTE>quote:</font><HR>Originally posted by Rob/1: why? What is everyones problem! Its like I have done anthing to you. Well if I have sorry. Can we get back to CM now.<HR></BLOCKQUOTE> You attempted to write the word 'different' twice. You spelled it wrong both times. You spelled it differently both times. At least be consistent with your mistakes. I have nothing against you but it's difficult to understand what you are writing with 50% of your post spelled wrong and with no punctuation. ------------------ And if we abandon any platform, I can assure you it will not be the Macintosh. -Steve My website! A major source of Wild Bill scenarios! Link to comment Share on other sites More sharing options...
ianc Posted January 2, 2001 Share Posted January 2, 2001 <BLOCKQUOTE>quote:</font><HR>The Pershing and the Jackson have diffrent blasts sranths<HR></BLOCKQUOTE> I tend to agree Rob. I'm sure you have some interesting and helpful stuff to say, but this may be a good time to bring up a favorite quote of my dear old Dad's: "If a job is worth doing, it's worth doing right". If what you have to say is important enough to post, it's important enough to take the extra minute to proofread it to make sure people actually know what you're talking about! Take care, ianc Link to comment Share on other sites More sharing options...
Rich90TO Posted January 5, 2001 Share Posted January 5, 2001 Hey guys, just visiting. JaJa posted part of a reply in another forum and I thought I would pass the info I have found back to you all. 90mm guns in use in World War II, according to the Ordnance Department Terminal Ballastics Manual were: The AA Gun M1, M1A1, and M2. The Tank Gun M3 on Medium Tanks T25E1 and T26E1, the Gun Motor Carriage T71 (prototype M36) and T71E1 (standardized M36), and the Heavy Tanks M6 and M6A1. These were all the same L54 gun with detail improvements (direct controls, auto ramers and so forth on the AA gun, the M3 tank gun was also available with or without muzzle brake). There was also an experimental higher-velocity 90mm gun the T15E1 "needle gun" which was mounted in one (?) T26E1-1 tank. It was an L73 monster that required mounting equilibrators outside the turret to balance it. See Belton Cooper's "Death Traps" for info on the single one of this type that got to the ETO. Postwar the T15E2 gun with fixed ammunition was developed and mounted in an improved turret with internal equilibrators, but only two were built as the T26E4. It is old but the Profile Publicatations "Armoured Fighting Vehicles in Profile Volume 4 American AFV's of World War II" has some good info. Part of the confusion may be that postwar the M3 90mm gun was redesignated the T119 gun in the M47. Depending on the gun mounting and muzzle brake design it was remeasured as either an L40.9 or L43. It was later produced with a longer barrel as the T139 L48 in the M41 tank. And yes, the US Army does try to be confusing on purpose. It is all part of the mystique. Hope this helps. Richard Anderson Link to comment Share on other sites More sharing options...
LynnL53 Posted January 5, 2001 Share Posted January 5, 2001 In the book "Pershing" by R P Hunnicutt-- he says the difference between the 2650 and 2800 fps load was the powder charge-- not so much barrell length-- although in the so called super Pershing they did both by giving the gun a long --L70+ barrell length and two part ammo with much more powder giving about 800 or 900 more fps-- except for the Tungston ammo the normal apbc was soft which limited it's performance some what at least in the normal loads of 2650 and 2800-- the Pershing and it's gun was aimed at matching the tiger I and it's gun which they did but Hunnicutt gives the Panther the edge in frontal protection Link to comment Share on other sites More sharing options...
Polar Posted January 5, 2001 Share Posted January 5, 2001 Wat do you guys meen he wrkts prfectlly good! THose difrant blasts sranths are defunitly wat makes shots differunt. Just kidding Rob. Joe ------------------ "I had no shoes and I cried, then I met a man who had no socks." - Fred Mertz Link to comment Share on other sites More sharing options...
Rich90TO Posted January 5, 2001 Share Posted January 5, 2001 The US 90mm guns in use in World War II, according to the Ordnance Department Terminal Ballastics Manual were: The AA Gun M1, M1A1, and M2. The Tank Gun M3 on Medium Tanks T25E1 and T26E1, the Gun Motor Carriage T71 (prototype M36) and T71E1 (standardized M36), and the Heavy Tanks M6 and M6A1. These were all the same L54 gun with detail improvements (direct controls, auto ramers and so forth on the AA gun, the M3 tank gun was also available with or without muzzle brake). There was also an experimental higher-velocity 90mm gun the T15E1 "needle gun" which was mounted in one (?) T26E1-1 tank. It was an L/73 monster that required mounting equilibrators outside the turret to balance it. See Belton Cooper's "Death Traps" for info on the single one of this type that got to the ETO. Postwar the T15E2 gun with fixed ammunition was developed and mounted in an improved turret with internal equilibrators, but only two were built as the T26E4. It is old but the Profile Publicatations "Armoured Fighting Vehicles in Profile Volume 4 American AFV's of World War II" has some good info. Part of the confusion may be that postwar the M3 90mm gun was redesignated the T119 gun in the M47. Depending on the gun mounting and muzzle brake design it was remeasured as either an L/40.9 or L/43. It was later produced with a longer barrel as the T139 L/48 in the M41 tank. The difference in the TM cited is probably due to those guns with the muzzle break being capable of developing higher chamber presssures from slightly more powerful cartridge case loads. Or it could be test variations or a comparison between the M3/T119 gun and the T139 gun. In either case it is doubtful if their was a marked performance difference between the US 90mm guns in use in World War II except in the ammunition utilized. The APCBC round, HVAP round and T round all had different performance characteristics, but only the APCBC was available until very late. And yes, the US Army does try to be confusing on purpose. It is all part of the mystique. Hope this helps. OOPS Sorry for the duplication. [This message has been edited by Rich90TO (edited 01-05-2001).] Link to comment Share on other sites More sharing options...
Olle Petersson Posted January 11, 2001 Share Posted January 11, 2001 Regarding various ammo types, there's this interesting thread going on at AFV-news: 75mm vs 76mm vs 17pdr vs 90mm Read the various postings, it's worth it! Cheers Olle ------------------ Srategy is the art of avoiding a fair fight... Link to comment Share on other sites More sharing options...
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