Using one of these is really an inexact science and mostly "feel" in seating the bullet onto the lands at the same pressure everytime. This is VERY hard to do. Agreed by most all, not possible and will give different readings most all the time. As you become more atune to doing it the deviation will lessen. Your readings you gave had a deviation of .063 over just 5 times. This is not very many times to get used to doing it. Probley getting it down to a deviation of .02X - .03X and then taking the average over a number of readings is the best one can do. Also the accuracy of the gauge must be considered also. PRACTICE, PRACTICE, PRACTICE.In my never ending search to improve my overall shooting, I have purchased a Hornady COL gauge
OK so I watch you tube video's on how to do it, and then think to myself, "hey this is easy enough", so I grab the .222 and its out into the shed.
MMmmmmmmmmmmmmmmm, ( a bit more !)
I am just touching the lands, with the slightest of pressure, and with my cleaning rod am tapping the projectile back off the lands, and then reseating the projectile back onto the lands again.
Reading 2.192", and am very proud of myself.
I do a 2nd, 3rd, 4th, and 5th reading, only to discover that everyone is different, ranging from 2.192"-2.255"
Now I am confused, and left wondering if I have wasted my money.
Is it me that has not got the feeling ?
Have I got a slight ridge in the chamber, that might be tricking me ?
Has my Irish herritage really kicked in ?
Any help would be appreciated
I assume you are doing this to increase or lessen the JUMP of the bullet onto the lands. Playing with OAL to find the right formula for ONE HOLE GROUPS culminates with with the OAL. Weather the jump is .01 or .025 or "0" when you find the magic OAL the jump (whatever it may be) will be what it is.