Barrel Wall Thickness Readings

[edgarspencer]

I considered using a replacement dial indicator tip, which would have required milling a flat on the rod, sufficient such the the dimension from tip-to- back of rod was less than .550”. The whole reason for making the new rod was to measure 28 gauge barrels. Damn tips are more expensive than Harbor Freight dial indicators.
As John Hosford showed in his video, aligning the indicator tip, to the ball is delicate; more so, the smaller the inner tip.
Without question, a finer tip inside the ball will more accurately measure bore pits, however I didn’t anticipate doing barrel evaluations on guns for others, as much as I wanted something for my personal use. I really don’t buy so many guns, and of questionable pitting to offset the smooth needle characteristics given with the .500” diameter ball

[MD*GSP]

Originally Posted by edgarspencer

I considered using a replacement dial indicator tip, which would have required milling a flat on the rod, sufficient such the the dimension from tip-to- back of rod was less than .550”. The whole reason for making the new rod was to measure 28 gauge barrels. Damn tips are more expensive than Harbor Freight dial indicators.
As John Hosford showed in his video, aligning the indicator tip, to the ball is delicate; more so, the smaller the inner tip.
Without question, a finer tip inside the ball will more accurately measure bore pits, however I didn’t anticipate doing barrel evaluations on guns for others, as much as I wanted something for my personal use. I really don’t buy so many guns, and of questionable pitting to offset the smooth needle characteristics given with the .500” diameter ball

The tips would be the cheaper part of the endeavor b/c I'm thinking they would require modification to make them work (ie: the .55 dim you mentioned). It would take a little fine machining to make the working end of the gage work-out just right.

The tips in the photo are Starrett but that's only b/c I buy Starrett everything. There are cheaper alternatives through company's like Enco etc. Also, if one did want to stick with Starrett tips, they can be purchased individually.