you have to set the barrel back to clean up a 280 chamber, I don't see anyway to set the barrel back on a handi rifle.
"The 280 Ackley Improved and the 280 Remington Improved RCBS are basically the same except for shoulder angle. With the standard chamber and neck diameter of 0.318, the factory 280 Remington cartridges can be fired to produce the improved cases. The neck junction is set back 0.004" in the 280 AI chamber for a tight fit when standard 280 Remington cases are fired.
Fire forming will shorten the cases by 0.012" to 0.015". The common chamber dimensions are: base 0.469", shoulder diameter 0.455", neck 0.318, chamber length is about 2.555 depending on reamer maker
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