Will normal Small Rifle primers work ok?
I don't think that "sure" is a very good answer here. In the 1980s a popular wildcat was the .22 CHeetah, a special .308 case necked down to .22 caliber and swaged for small rifle primers. The first reports in the press were stellar, telling of the cartridge's amazing accuracy and velocity. All was well in the summer, but as more and more owners took their rifles out in cold weather reports surfaced of poor ignition. Small rifle primers were designed to ignite around 30-35 grains of powder, while most all top loads in the .45-70 exceed 50 grains.
Bottom line, they may work great in hot weather, but fail in cold. .45-70 cases are not expensive, why take the chance?
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