Masshuntr, its rarely been an issue for me. Almost all my guns I could not reach within 2/100" to my rifling and still fit my magizine. I want a nice margin also in my magizine. I have tested the distance to my rifling both with the split case way, burnt carbon from a candle way, and magic marker way. None were very accurate or repeatable and when you did think you found it, you were really jammed into the rifling or far from it. I use a stoney point AOL guage now. If you do it right, and use a dowl or something to press against the bullet from the bore, you have remarkable sensitivity. And also shows you how much more you can push the bullet into the rifleing. What I have showed some people, is what they were doing was a tad wrong. They have tested using a split neck technique, and thought they were far from the rifling. But they always wondered why they can't reach max load or pressure signs sometimes. They were in the rifling. Pressure built quick.

Don't get too wrapped up in this. I did and it made reloading fussy and no fun. Unless you are a bench comp shooter. There is one bullet I find to be very finicky to COL and thats Barnes bullets. Only reason I want to measure it now to make sure I have safe loads. I have guns that shoot .5MOA with bullets sitting .25 away from rifling and others sitting .01" away. Lots more important things to worry about like bullet seating.

So now, I just use the tool to make sure I am not close to the rifling and load the bullet to fit my magizine or close to SAMMI specs. Lots of exceptions. Like Short action calibers in long action guns. Or varmint calibers. So if you lots of room in your magizine, sure you can play. Just make sure you are not in the rifling.