Path: spln!rex!extra.newsguy.com!lotsanews.com!news-out.cwix.com!newsfeed.cwix.com!nntp.abs.net!news-out.visi.com!hermes.visi.com!gemini.tycho.net.POSTED!not-for-mail Approved: sci-military-moderated@retro.com Return-Path: news@google.com Delivery-Date: Sun Dec 09 22:52:20 2001 Delivery-Date: Sun, 09 Dec 2001 22:52:20 -0800 for <sci-military-moderated@retro.com>; Sun, 9 Dec 2001 22:52:18 -0800 (PST) id 16DK2F-0005lK-00 for sci-military-moderated@moderators.isc.org; Mon, 10 Dec 2001 07:35:31 +0100 for <sci-military-moderated@moderators.isc.org>; Sun, 9 Dec 2001 22:35:30 -0800 for <sci-military-moderated@moderators.isc.org>; Sun, 9 Dec 2001 22:35:30 -0800 for sci-military-moderated@moderators.isc.org; Sun, 9 Dec 2001 22:35:30 -0800 To: sci-military-moderated@moderators.isc.org From: psl@interchange.ubc.ca (Paul Lakowski) Newsgroups: sci.military.moderated Subject: Re: Advanced tank main guns Date: 9 Dec 2001 22:35:29 -0800 Organization: http://groups.google.com/ Message-ID: <de5bf54f.0112092235.44a11df3@posting.google.com> References: <5dcb47db.0111130437.2f46f7dc@posting.google.com> <3BF20796.FEDA5A6A@yahoo.com> <f69851a9.0111150236.7f3f92ac@posting.google.com> <i08K7.9551$SJ3.84158@NewsReader> <f69851a9.0112060720.1b87db5a@posting.google.com> <9upc92$drt$1@news.panix.com> X-NNTP-Posting-Host: 207.23.94.43 Content-type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Complaints-To: groups-abuse@google.com X-NNTP-Posting-Date: 10 Dec 2001 06:35:29 GMT Content-Length: 1292 Lines: 27 NNTP-Posting-Host: 4d4adb7c.newsreader.tycho.net X-Trace: 1008038563 gemini.tycho.net 36736 205.179.181.194 X-Complaints-To: abuse@tycho.net Xref: spln sci.military.moderated:40817 Brian Trosko <btrosko@panix.com> wrote in message news:<9upc92$drt$1@news.panix.com>... > Juerg Hoelzle <jhoelzle@webshuttle.ch> wrote: > > 2000 m/s and more. The optimum velocity for a system (means energy > > imput)is around 1600 to 1800 m/s. It is more effective to make the > > penetrator longer than faster. > > This does not follow. If, as you suggest, "energy input" is what you're > trying to maximize, making the projectile a bit faster is considerably > more effective than making it longer. I'm afraid this is incorrect. As the striking velocity of the penetrator increases above ~ 1.8km/s the efficence starts to drop off as the value moves 'asymetotically' towards the Hydro dynamic limit value for that penetrator material Vs the armor material. Thus each incremental velocity increase reaps lesser benifits. Increasing the rod length by changing the lenght to depth can improve penetration until this reached about 35-40:1 at which point theirs effectively little increase in penetration. Also with current propellant tech it takes a dramatic drop in the projectile mass to increase the MV substantially, so you end up robbing Peter to pay Paul. Also it appears that higher velocity penetrators are more vulnerable to damgage from spaced and flyer plate arrangements.