Since the caliper readings are in reference to zero, a reading of 019 (or, more accurately, 0.019) is the smaller of the two. This reading is "nineteen thousandths of an inch".
5 inch gauge is garden railway but 3.5 inch gauge is the smallest elevated gauge for a railway http://www.rideonrailways.co.uk/
If there is no decimal, then 019 is bigger.
16 gauge
019
.019 is thicker.
Between 6 and 7 gauge. 6 is thicker at .194 inch. 7 is thinner at .179 inch.
i have a champion 12 gauge by iver johnson with a 36 inch barrel
1/2 inch is 12.7mm
no
There is a Noble 12 gauge-2 3/4 inch, 28 inch barrel for $650.00 TR
019 is bigger than 0.