Saturday, December 19, 2009

I need gun powder recommendation for reloading a 270 Winchester?

Which gun powder is good for a Winchester model 70 chambered for a 270 Winchester using Nosler's 150 grain Partitions?I need gun powder recommendation for reloading a 270 Winchester?
The late, great, Jack O'Conner, wrote in his book, the ';Complete Book of Rifles and Shotguns';.......';I have fired over 7,000 rounds through various .270's, and have found that 49 grains of IMR 4064, and a good 130 grain bullet is the flattest shooting, and most accurate load for this caliber.';....Most loading manuals list 47 grains of 4064 as a maximum, with 49 grains being on the high pressure side....With a 150 grain bullet, you would have to reduce even more........I did, work up from 47 grains, by one half grain increments to 48.5 grains. I carefully watched for gas leaks around the primer, and flattening of the primer, and metal ';flow';, to indicate high pressure. I noticed a slight flattening of the primer at around 48.5 grains. I backed off at this point. I have ';cast'; the chamber of my rifle, and know my maximum overall length, seating a ';secant ogive'; bullet 1/32 inch short of the lands. Perhaps my ';leade'; is less than the rifles Jack experimented with..........I like IMR 4064 in the .270. It is clean burning, and gives very consistant velocities, and it is accurate. I have shot many prarie dogs with the Hornady 110 grain hollow points, using 48 grains of 4064. I don't think I would use over 46.5 grains with the 150 grain bullet. Some manuals list 45 grains as a maximum load with 150 grain bullets. I have found that using 4064, I can use 47.5 grains, and the 130 grain, and the 110 grain will shoot to nearly the same point of impact.........You will have to experiment with your rifle to find which load works best in it, but IMR 4064 is a great powder for use in the .270...More consistant than any other I have shot.....Always, watch for the tell tale signs of high pressure. Start low, and gradually work up, and stop at the first sign of high pressure........I need gun powder recommendation for reloading a 270 Winchester?
IMR 4350 work for me.
Alliant Reloader 19 is a popular one.
IMR 4831. Jack's favorite load used H450 but that powder isn't available anymore. So I started testing and checking to see what would come closest to the pressures and performance of his old load. I fire a sierra BTspitzer point 150 grain bullet. I worked this load up in my rifle to 52.4 grains, with no indications of overpressure. New loading manuals say that is overpressure and don't list it. Older manuals show it as just fine. My friend has an identical rifle to mine, but his handles a hotter load then mine for some reason. I suggest you star at 48 grains and slowly work up, checking for any signs of overpressure after each test round you fire. Don't start at my load as each rifle is different.


Shoot safe
Hodgdon is now the manufacturer for IMR powders, and most of the ones with the same numbers are nearly identical. My Rem 700 in .270 does best with 50.3 grains of H4350 using a CCI number 200 primer and a 150 grain Hornady Spire Point. This load works best for me as it gives 100 yard groups with open sights from the bench which I can cover with a quarter. You have to work up a load for your own rifle which works for you. The others have given good advice, too, but some rifles work best with a narrow list of powders and bullets. Experiment until you find what is best.

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