{"id":1681,"date":"2011-10-17T19:23:39","date_gmt":"2011-10-17T17:23:39","guid":{"rendered":"http:\/\/www.retro.co.za\/blog\/?p=1681"},"modified":"2011-10-24T13:19:20","modified_gmt":"2011-10-24T11:19:20","slug":"7mm-international-rimmed","status":"publish","type":"post","link":"http:\/\/www.retro.co.za\/blog\/?p=1681","title":{"rendered":"7mm International Rimmed"},"content":{"rendered":"<p>The 7mm International Rimmed is a wildcat cartridge developed by Elgin Gates in the seventies. Nothing strange about it, take a 30-30 case, neck it down to 7mm, and there you are. You don&#8217;t need to trim the brass or anything.<\/p>\n<p><a href=\"http:\/\/www.retro.co.za\/blog\/wp-content\/uploads\/2011\/10\/7mmIntR.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-1682\" title=\"7mmIntR\" src=\"http:\/\/www.retro.co.za\/blog\/wp-content\/uploads\/2011\/10\/7mmIntR-300x133.jpg\" alt=\"\" width=\"300\" height=\"133\" srcset=\"http:\/\/www.retro.co.za\/blog\/wp-content\/uploads\/2011\/10\/7mmIntR-300x133.jpg 300w, http:\/\/www.retro.co.za\/blog\/wp-content\/uploads\/2011\/10\/7mmIntR-1024x456.jpg 1024w, http:\/\/www.retro.co.za\/blog\/wp-content\/uploads\/2011\/10\/7mmIntR.jpg 1401w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p>Before (bottom) and after fireforming.<\/p>\n<p>Compare this to the <a href=\"http:\/\/www.reloadingroom.com\/index_files\/7-30.htm\" target=\"_blank\">7-30 Waters<\/a>, developed by Ken Waters (also in the  seventies) <a href=\"http:\/\/www.ballisticstudies.com\/Knowledge+Base\/7-30+Waters.html\" target=\"_blank\">specifically for levergun use<\/a>. It&#8217;s also a 30-30 case necked  down to 7mm, but in this case the neck is much shorter, giving more case  capacity and of course more velocity.<\/p>\n<p><a href=\"http:\/\/www.retro.co.za\/blog\/wp-content\/uploads\/2011\/10\/7-30_Waters.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1683\" title=\"7-30_Waters\" src=\"http:\/\/www.retro.co.za\/blog\/wp-content\/uploads\/2011\/10\/7-30_Waters.jpg\" alt=\"\" width=\"285\" height=\"240\" \/><\/a>30-30, necked to 7mm, and fireformed. (<a href=\"http:\/\/www.levergunscommunity.com\/viewtopic.php?p=373065#p373065\" target=\"_blank\">Image source: levergunscommunity.com<\/a>)<\/p>\n<p>I&#8217;ve been shooting the 7mm TC\/U in my 14&#8243; Thompson Contender for a few years. Nothing wrong with the cartridge, shoots great, adequate power and everything&#8230; but the 7mm TC\/U headspaces on the shoulder, and that means that if you don&#8217;t get your resize operation just right, you either can&#8217;t close the gun, or your brass stretches and the case head separates after a few shots. I carry a tap in my shooting box, this has saved the day for me and for at least one other shooter caught with half a case stuck in the chamber. A TC ideally needs a rimmed case.<\/p>\n<p>So I had the choice of 7-30 Waters or the much less popular 7mm IntR, and I chose the latter because, as I said, the 7mm TC\/U already has enough power for what I need to do, I don&#8217;t need power, I just need a rim on the case.<\/p>\n<p><strong>7TC\/U<\/strong> : 25.5gr S335 : 145 grain cast RCBS-145-SIL : 2000fps : my 7mm TC\/U silhouette load, accurate.<\/p>\n<p><strong>7mm IntR<\/strong> : 29gr S335 : 160gr jacketed : 1900fps : accurate, 3 shot velocity spread = 6 fps, SD = 3.<\/p>\n<p><strong>7-30 Waters<\/strong> : Factory load : 120gr Nostler : <a href=\"http:\/\/www.reloadbench.com\/cartridges\/730w.html\">2400 fps from 14&#8243; TC barrel<\/a>.<\/p>\n<p>I think 7mm International Rimmed is the best 7mm TC silhouette shooting option, now to do some further <a href=\"http:\/\/www.retro.co.za\/gundex\/cartridges\/7mm%20International%20Rimmed.html\">load development<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The 7mm International Rimmed is a wildcat cartridge developed by Elgin Gates in the seventies. Nothing strange about it, take a 30-30 case, neck it down to 7mm, and there you are. You don&#8217;t need to trim the brass or anything. Before (bottom) and after fireforming. Compare this to the 7-30 Waters, developed by Ken Waters (also in the seventies) specifically for levergun use. It&#8217;s also a 30-30 case necked down to 7mm, but in this case the neck is much shorter, giving more case capacity and of course more velocity. 30-30, necked to 7mm, and fireformed. (Image source: levergunscommunity.com)&#46;&#46;&#46;<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"class_list":["post-1681","post","type-post","status-publish","format-standard","hentry","category-guns"],"_links":{"self":[{"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1681","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1681"}],"version-history":[{"count":4,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1681\/revisions"}],"predecessor-version":[{"id":1685,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1681\/revisions\/1685"}],"wp:attachment":[{"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1681"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1681"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1681"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}