Talk:Royal Ordnance L7

Merge with "L7 (tank gun)"

Maybe merge this page with L7 (tank gun)?

Good idea, material from it taken and merged in. GraemeLeggett 12:17, 25 September 2005 (UTC)

Would like to add recoil for L7 on Leo C1

Hi, as an ex Leopard C1 gunner I'd like to add that the L7 recoil on a Leo C1 was/is 25cm.10:55, 13 February 2006 (UTC)~~ Hi, Same guy again. Canada also had a training round for the HESH called "SH-T P", Squash Head-Tracer, Practice, otherwise known as the cement round. Being filled with cement in place of the plastic explosive.204.50.113.29 (talk) 22:10, 17 November 2008 (UTC)And me again, we also had "Smoke, BE" (base ejection) in the first half of the 1980's 142.52.81.11 (talk) 22:08, 8 April 2015 (UTC)

Sources

Maybe we could add sources for the date posted on this page? --Edward Sandstig 22:48, 21 August 2006 (UTC)

Response to T-54A

Steven Zaloga, writing about T-62 development:

...the program took an abrupt shift in January 1961 after a disgruntled Iranian officer drove his brand new M60A1 tank over the border into the Soviet Union. The US Army's M60A1 armor layout and its new 105mm gun infuriated the chief of the Soviet tank force who insisted that the caliber of the new Soviet smoothbore gun be increased from 100mm to 115mm to exceed the NATO 105mm ... Ironically, the British 105mm gun had been adopted by NATO in the late 1950s after British officials examined a T-54A tank driven onto the grounds of the British embassy in Budapest during the 1956 Hungarian uprising.

—Steven J. Zaloga and Hugh Johnson (2004)
T-54 and T-55 Main Battle Tanks 1944–2004, p 11.
Oxford: Osprey. ISBN 1-84176-792-1.

 —Michael Z. 2006-10-04 03:21 Z

This makes a nice story, but unfortunately does not seem to agree with facts from other sources. The Hungarian Uprising was in late October of 1956. Conversely, historians of tank gunnery (e.g. Ogorkiewicz, cited on the Ordnance QF 20 pounder page) indicate that the L7 development program began before then -- long before then, with the first test guns ready for firing in 1954. Further, the maximum armour of the T-54A just wasn't anything like impressive enough to spur some sort of crash development program. Maximum armour is ~200 mm on the front of the turret, with most of the armour less than half that. The existing 20 pdr British tank gun, in service since 1948, was already not only to able to defeat any part of that armour, but totally overmatched it even at extreme range. The then current generation of British infantry AT weapons -- recoilless rifles -- also seriously overmatched this level of armour, and did it with hideous behind-armour effect, at any range they could hit. Even the 17 pdr AT gun (considered obsolescent by this point, but still in service), using its best AP ammo (APDS, which had high penetration but an accuracy problem), could defeat any part except the front of the turret at 1,000 yds (if it could actually hit it!), and had a good probability of defeating the front of the turret at 500 yds. So in short, this story doesn't make a lot of sense. -- 203.20.101.203 (talk) 06:53, 26 November 2009 (UTC)

Oh, and while I'm at it, the first part of the story seems unlikely, too. The M60 Patton only arrived in US service late in 1960 (some sources say "fall", some say "December"), and were immediately rushed to West Germany to counter fears of Soviet invasion; it seems extremely unlikely that any were in Iran as early as January 1961. Furthermore the M60A1 variant wasn't even built until 1963. As other sources agree that the version sold to Iran was indeed the M60A1, it would seem that any such incident can't have occurred prior to 1963 at the earliest. But the development history of 115 mm U-5TS (2A20) gun on the T-62 has long been published, and it was already undergoing acceptance trials in early 1960, and the complete tank entering mass production in July 1961. If either of these stories have any basis in reality (and I would like to see much more detailed & specific references before being convinced of that), then they seem most likely to have simply been cover stories for espionage programs that penetrated the opponent's development program much earlier than the suggested dates. -- 203.20.101.203 (talk) 07:47, 26 November 2009 (UTC)

I suspect the 105mm was designed to give the Centurion adequate performance against the IS3 that at the time the 120mm Conqueror tank was intended to combat. — Preceding unsigned comment added by 80.7.147.13 (talk) 20:26, 11 November 2013 (UTC)

I have read a lot within the past few years about the 17 pdr's alleged inaccuracy using APDS but the simple fact is that if the shot hits six inches high or low, or six inches to the left or right, of the aiming point at a range of a mile on a tank turret or hull target several feet wide, it's not likely to make much difference. The target is still going to get knocked out. Whilst it's possible that early test APDS rounds had accuracy affected by the sabot separating non-cleanly, one suspects that this would have been solved long before the rounds entered production.

Providing the gunner can hit an average-sized tank turret at a range of a mile or so, then extreme accuracy is unimportant. If this had not been possible with APDS it would never have been issued. You see, with APDS one didn't need to aim at a specific, i.e, weakest point, in the target vehicle's armour. In ranges up to a mile it would go through any part of any vehicle one was likely to encounter in 1944-45.

And whilst I cannot claim to have read everything, I will state that in the not inconsiderable amount of reading of anecdotal accounts of British Army battles, encounters, etc., over a number of years, I have never read of even one complaint from a gunner about the accuracy of the 17 pdr and APDS. Come to think of it, I don't recall ever reading of a 17 pdr gunner using APDS ever having to fire at anything more than once.

Early APDS test rounds had problems with getting a clean separation of the sabot and shot upon leaving the barrel so in order to ease this the pot was made to fit less tightly around the shot and this solved the separation problem. Unfortunately it was then discovered that accuracy was poor, and it was only some time after a considerable number of test rounds had been produced that it was discovered that the too-loosely fitting pot was not transferring the spin imparted by the rifling to the enclosed projectile. Once this was corrected, accuracy was restored, and the rounds were then finally issued to troops. Hence some test rounds that were supplied did have accuracy problems. — Preceding unsigned comment added by 95.150.18.209 (talk) 09:39, 15 September 2017 (UTC)

That doesn't answer the main question though:

"During the Hungarian Revolution of 1956, a Soviet T-54A medium tank was driven onto the grounds of the British embassy in Budapest by the Hungarians. After a brief examination of this tank's armor and 100 mm gun, British officials decided that the 20 pounder was apparently INCAPABLE OF DEFEATING ITS FRONTAL ARMOR. This meant the most common British tanks were NO LONGER ABLE TO DEAL WITH SOVIET MEDIUM TANK DESIGNS, let alone their heavy tanks."

So why is this still a part of the page if it's a proven lie? We know it was capable of doing alright, it just wasn't providing _complete superiority_ over soviet tank at real battle distances. And that one is mostly affected not by armor of T-54/55, but by its CANNON. Weapon development is usually aiming for superiority with the opponent, not just "catching up". Should those lines be deleted? 37.214.74.83 (talk) 23:11, 5 October 2020 (UTC)

L7 used by Stryker

I've removed the sentence stating the L7 is also used by the Stryker. The Mobile Gun System variant of the Stryker uses the Watervliet Arsenal 105mm low recoil gun. (Zaloga: Stryker Combat vehicles)2001:630:63:80:1CD4:E229:F9A3:51EF (talk) 11:00, 17 April 2014 (UTC)

I've put it back in, mostly on account of me being wrong!Loates Jr (talk) 22:07, 17 April 2014 (UTC)

¿Correcting errors for the M&8A1E2?

@Sovngard:

I am moving your contribution to the US history section and reverting it to the former entry for two reasons. First and foremost, the Hunnicutt ref that you have used to justify this info does not match with your provided info. I have direct access to US military libraries (and all 5 complete volumes of the Hunnicutt History of the Main battle Tank). If I am correct, I believe your source information was taken from global security. and you should note that. My original entry that you replaced does correspond with Volume 2 pg. 202 of Hunnicutt ref. This is generally considered a preferred source of information.

Secondly the formatting of your entry does had add further history of the gun´s use and eventual replacement and would best serve the readability of the article by moving it to the US history section of the article. CIB2008 OEF (talk) 12:03, 20 November 2019 (UTC)

Your sources don't match what you write in the L7 article. Firstly, your source about the XM24/L52 barrel doesn't contain any reference to the XM24 barrel. Secondly, as I have said several times (sources here (Army Appropriation FY 1987), here (Hunnicutt) and here (Rock Island Arsenal Annual Historical Review)), the XM24 barrel (also called gun tube) was related to a longer tube project for the M68 (1.5 meters / 4.9 ft and not your 1.5 ft, thus not a mere L/55). You don't seem to understand what is written in the sources. Thirdly, it's breech and not breach as you have written. The same goes for your fictious M744A1 cartridge and the well-known M774 APFSDS (dyslexia ?) or your hybrid "L11/M256 gun" (two different guns). If you keep writing false information with sources doesn't match what your are writing, I will have no other choice but to revert your edits. --Sovngard (talk) 17:50, 31 May 2020 (UTC)

References

No performance data

Am I blind or is there nothing at all said here about the performance parameters (except the range)? Where is the information on ammunition, muzzle velocity, penetration, accuracy, service life? Can't believe this is all still secret. WerWil (talk) 14:55, 1 January 2024 (UTC)

105×617mmR FORMATOSE (talk) 15:58, 1 January 2024 (UTC)