Tool for checking Vent Hole Size
 

Too hot and windy to shoot here in KS. I've been knocking off the " Honey Do " projects and have had a little time to mess around with the guns.

I'm trying to get my hands around the erosion rate on BP's and Vent Liners. With no way of actually measuring the hole size, I could do little more than ponder.

While at Home Depot for another project, I swung by the welding section. They had an acetylene torch tip cleaner kit which had cleaning wires for a wide range of sizes. It's made by Lincoln Electric and cost $3.97



Right next door were tips ranging from .025 to .035. A quick bit of trial and error and I found the the 5th largest wire is .035 and the 6th largest wire is .030. I had to go down to the 9th to get to .025.



Anyway, I thought I'd share in case others are interested in a quick and cheap way to get a handle on the hole dimensions. It will double as a cleaning tool so I feel it's worth the $4.

FYI - My Lehigh Vent Liner shows no wear with 200+ shots. I still can't get the .030 wire through.

That's incredible! Is that one of the older removable ones or one of the new ones that is brazed to the breech plug???

It's about 4 years old. The removable style.

Almost all BH 209, some T7. I rarely shoot more than 100 grains. Perhaps that has something to do with it?

What it mostly has to do with, is your measuring device isn't accurate.

I went back and counted up all of my saved targets and checked how many bullets I've gone through. The best I can guess is somewhere around 250 shots fired. I edited the original post to reflect these changes.

As Ron points out, my tool may not have the accuracy need to determine changes in the hundredths of an inch.

Josmund

I have an original Lehigh Vent Liner in one of my 50's that I have at least 300 shots through and yesterday after reading one of you posts, I did measure it with a pin guage. It will accept a .033 but will not take a .034

All T7-2f and most of those shots would be with 120 grains of T7.

Original Lehigh Vent liners are drill .031 +/-