Do yourself a favor and ditch that tool. Stop measuring the lands. It’s meaningless. Measuring jam is more accurate and you can start at Jam - 20K, and shoot 3k increments. Eric cortina has a great video on YouTube (I think it’s called something like “stop chasing the lands”)
The side wall of the hole doesn’t contact anything. It’s the corner of the hole that sits on the ogive of the bullet. I measured my commercial ones and they appeared to be about .011 less than the bullet diameter. Using that, I’d need a .253 hole. Don’t have much of a metric or reamer collection so I went with .257 (an F I think).Bein a crotchety old Die-maker , you might want to "feather polish" that hole a little , just to keep from getting false readings . Since you have the tooling , you could always drill out , and polish a smaller caliber piece , or just make one to fit your tool from brass , to the inner diameter you want . And I have no problem figuring out ways to create extra work for others .
This isn’t a bolt gun and I have no plans on being in the lands. I am just looking for a not to exceed length. Some of the bullets I have won’t get anywhere near the lands, they’re too short.
I've seen the video, don't remember the exact details , but what I remember is not quite what you are saying.
yeah the tool is not very useful for large frame gas guns. Unless you are going to single feed you will never get close to the lands and still fit in a magazine.
