Printable View
rondog,
Go to surplusrifle.com, and look at the subsections along the left side of the main page. You will see Type 99 Arisaka listed there. Pull it up; along the right side of that page there are articles about shooting the Type 99 that describe modifying .30-06 and 8MM Mauser brass to 7.7 Japanese. They also describe how to slug the bore, just in case you're interested in doing that.
I slugged mine just last week by using their tutorial; the barrel on mine mic'd at .313.
It's very easy. Lube sparingly (castor oil is good), run the '06 case into a 7.7 Arisaka FL sizer, trim to length, deburr.
https://www.milsurps.com/images/impo...8forming-1.jpg
Using 8x57 cases can be problematical, since they're a little short in both total and head/shoulder dimensions. Normally, the tiny secondary shoulder left then the 8mm neck is reduced provides adequate headspace support for fire forming - but it's advisable to check end-play before firing normal loads.
https://www.milsurps.com/images/impo...adspacec-1.gif