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Boresize Guide in HK VP9
Boresize Guide in HK VP9

On a return trip from a recent range session, I was dropping Freeze off and unloading his gear from the truck. While we were standing around, I noticed a small tool on the end of some keys in his garage. He eye’d me knowingly and stated, “You don’t know what that is do you?”

It’s easier not to lie in life. Especially to Freeze. His bullshit meter is very sensitive. “No. But you know that already. I assume it’s a walk up-hill in 6-feet of snow, both ways, kinda thing?”. That got a chuckle.

Boresize Guide next to CCW Pistol.
Boresize Guide next to CCW Pistol.

He explained that back in his old black powder days, seeing a used rifle on a table often left more questions than answers. You see, many period BP rifles were custom made by hand. And many times they wouldn’t be marked with the caliber. Or…perhaps the caliber had been converted? Or…what if the maker “thought” was 40 caliber is really 39 or 41 when you measure it? Bottom line, you can’t trust the seller or he markings on the barrel.

The only way to be sure was to have a tool to measure on the spot.

Boresize Guide in CCW Pistol. VP9
Boresize Guide next to CCW Pistol.

While this may seem bizarre to us today, you have to remember that most mechanical devices made before the Industrial Revolution were completely hand made. Gears, screws, etc. You see, Henry Ford didn’t invent the car. I am amazed how many people think he did. No…he perfected the mass produced car. Big difference. Before Ford, many cars were built onesies and two’sies. ┬áThe same problem exists with old guns. So when looking at antique firearms, you need a quick way to determine what you are actually┬ádealing with. Was 38 actually 38? Or was it 40? Or maybe 36.9? Or maybe bored out to 45?

Glad I asked. It was an interesting conversation. I always enjoy learning something new.




“Shooting Guns & Having Fun”



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