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You do not mention the specifics of the bullet, brass and rifle. Using a 24 inch barrelled CZ 550, Hornady's minimum load with their 525 grain bullets is 127.3 grains of H-4831 in Bertram brass. They obtain 2000 fps using this load. Pierre van der Walt's excellent book, African Dangerous Game Cartridges, and the A Square manual both show 131.5 and 132 grains of H-4831 only and respectively. With a maximum pressure of only 39160 psi, hang fires and secondary explosions are a very real possibility with too little powder. If what happened to you had happened to PH Robert Wilson, the famous Hemingway tale of "The Short Happy Life of Francis Macomber" would have been much shorter and less interesting.

I realise that the Hodgdon Extreme powders are very popular, especially with their claim of temperature insensitivity, but they are designed for modern high pressure rounds. At less than 60 000 psi, it has been my experience that the slower burning Extreme powders are less efficient than older powders such as IMR 4831 and IMR 7828. They(the IMR numbers) will still burn cleanly at 40,000 psi. These two older IMR slow burning powders are also some, if not the coolest burning slow burning powders available. I could not get H-4831 or H-4350 to shoot in rifles that have proven themselves accurate in the 270 Winchester and the 30:06 without the use of magnum primers. Remington 9 1\2 magnums in each case improved accuracy and reduced the significant carbon fouling I was getting with these Extreme powders in these standard cases.

Hornady tops out with 133.9 grains of H-4831 with their 525 grain bullets. They get 2150 fps with this top load of H-4831. Hornady is unique in that their solids and softs are generally able to take the same load without problems. Not all solids and softs from other makers have this ability. Hornady used F-215 caps with their loads. As ATK owns both CCI and Federal, it is my understanding that the CCI large rifle magnum primer and the Federal large rifle magnum primer can be used interchangeably without load changes.

I would recommend obtaining a Lee factory Crimp die for this calibre to aid in consistent neck tension for more reliable ignition and to reduce the possibility and or severity of bullet set back. These Lee Factory crimp dies are a must for any heavy kickers that your life may depend upon in my opinion.

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