The 7x65R By Chuck Hawks The 7x65R is a rimmed bottleneck cartridge designed by Wilhelm Brenneke that owes its existence to the Germanic fascination with break-open rifles. Break-action guns function best with rimmed cartridges, hence the necessity for a rimmed version of the popular 7x64 Brenneke rimless cartridge. True to its European nomenclature, the 7x65R uses a case 65mm (2.559") long. The shoulder angle is 20.25 degrees and it uses standard 7mm (.284") bullets. Norma, Sako, RWS (and probably other European ammunition companies) offer factory loaded ammunition for the 7x65R. In the US, Norma offers four factory loads for the 7x65R, three with 170 grain bullets and one with a 156 grain bullet. The Norma 156 grain Oryx bullet is loaded to a MV of 2723 fps and ME of 2569 ft. lbs. The 200 yard figures are 2200 fps and 1678 ft. lbs. The 170 grain Vulkan load has a MV of 2657 fps and ME of 2666 ft. lbs. The 200 yard figures are 2143 fps and 1734 ft. lbs. The sixth edition of the Hornady Handbook of Cartridge Reloading covers the 7x65R. The Hornady technicians found that IMR 4831, IMR 4350, and VIHT N-160 powders gave the best accuracy and overall performance. For use in break-open guns they suggest loading their 139 grain Spire Point bullet to a MV of about 2600 fps. This can be achieved in front of 50.6 grains of IMR 4831 powder. The ME at that velocity would be 2087 ft. lbs. The Hornady trajectory table shows the following: +2.4" at 100 yards, 0" at 200 yards, and -10" at 300 yards. Hornady suggests that their 154 grain Spire Point bullet be loaded to a MV of about 2500 fps in break-open guns. This can be done with 49.4 grains of IMR 4831 powder. The ME at that velocity would be 2138 ft. lbs. and the trajectory would look like this: +2.6" at 100 yards, 0 at 200 yards, and -10.8" at 300 yards. These Hornady loads used RWS cases and Federal 210 primers. Velocities were taken in a 26" rifle barrel. Note: A full length article about the 7x64 and 7x65R can be found on the Rifle Cartridge Page. |
Copyright 2005, 2013 by Chuck Hawks. All rights reserved.
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