Thread: Defence dept go/no go gauge?

Agree, it looks like a go/no go gauge. What are the disatnces between the "horns" on each side, and across the end of the "horns" at each end?

The gap is just over 86mm, the horns are 9mm

The measurements will make more sense in imperial I reckon.

3 13/32" is roughly 86.52mm if that helps

What is the dimension across the horns - top to bottom in the photo?

That is a tool that seems to have fallen out of favour with wood workers these days, perhaps the result of less repetitive manufacturing. I make some simple gauges or set an old vernier as a go, no-go gauge. The actual measurement isn't so important but the fit of one item to another is.

Dimensions in imperial

I really don’t think it’s a go/no-go gauge; the manufacturing is too... well, wrong. It’s a piece of pressed steel so it couldn’t be used on anything precise, plus it has been given a polished nickel plated finish, totally unnecessary for a gauge.

I think the mirror-like finish is the key to its purpose, perhaps it’s a reflective bore sight for an artillery piece? I know I’ve seen something similar on warships but can’t think what it was.

Ok. Pulling this one completely out of nowhere.
Was your grand-dad in the infantry or did he have something to do with shooting as a sport later on?

I believe the Australian army used .303 for rifles and according to wiki, .30 calibre was introduced into commonwealth use around 1940. The bullets measurements seem to be within a foofteenth of each other , except the length of the 303 is 78mm and the 30-06 is 85 mm (from wiki).

Could it be a length guage for .30 calibre bullets to differentiate them from .303 bullets?

Regards
SWK

An Australian military history site may have the answer.

Thanks SWK, my gf was never in the military or involved in shooting to the best of my knowledge