Once you have slugged the barrel you should use a bullet .001 larger than the Groove dia. I read once of an old guy who used to drive his bullets through a hole he had in a piece of scrap steel. I have an old 30/06 full length die. the top end is not threaded. the opening is .312. I ground the mouth to soften it and I use it inverted to size bullets for my 303 and 7.65Arg. I use the push rod that come with me .309 lee sizer. It works great. You can size by drawing through a hole, you just can't make great reductions in one pass as you risk gross deformity. Best of luck, JB
