What is this massive rifle?

[<<Genesis93>>]

The number represents the reciprocal of the fraction of a pound that a single lead ball (sphere) that is sized per the bore would weigh.

12g =1/12 pound lead ball = 0.73inch ball = 18.5mm lead ball
10g = 1/10 lb = 0.78inch = 19.7mm
8g = 1/8 lb = 0.84inch = 21.2mm
4g = 1/4 lb = 1.05inch = 26.7mm
2g = 1/2 lb = 1.33inch = 33.7mm
1g = 1 lb = 1.67inch = 42.4mm

[duncan61]

Thank you for that I always wanted the true scaling

[brett1868]

The number represents the reciprocal of the fraction of a pound that a single lead ball (sphere) that is sized per the bore would weigh.

12g =1/12 pound lead ball = 0.73inch ball = 18.5mm lead ball
10g = 1/10 lb = 0.78inch = 19.7mm
8g = 1/8 lb = 0.84inch = 21.2mm
4g = 1/4 lb = 1.05inch = 26.7mm
2g = 1/2 lb = 1.33inch = 33.7mm
1g = 1 lb = 1.67inch = 42.4mm

Cool, once again I've learnt something from you

Shot size, I was told it was the number of pellets that would fit into the diameter of the bore. For example No.8 shot in 12ga would be 8 pellets to the diameter, is this true or make sense?

[<<Genesis93>>]

The number represents the reciprocal of the fraction of a pound that a single lead ball (sphere) that is sized per the bore would weigh.

12g =1/12 pound lead ball = 0.73inch ball = 18.5mm lead ball
10g = 1/10 lb = 0.78inch = 19.7mm
8g = 1/8 lb = 0.84inch = 21.2mm
4g = 1/4 lb = 1.05inch = 26.7mm
2g = 1/2 lb = 1.33inch = 33.7mm
1g = 1 lb = 1.67inch = 42.4mm

Cool, once again I've learnt something from you

Shot size, I was told it was the number of pellets that would fit into the diameter of the bore. For example No.8 shot in 12ga would be 8 pellets to the diameter, is this true or make sense?

Well... thats all the learning I gots to give you ... I know where to go when I take up 50cal shootin though..

The sizing of shot is generally in hundredth of an inch increments or multiples, so the shot to the bore thing doesnt work, perhaps the ratio works for one particular size as a coincidink..

Note there are several sizing schemes, some overlap, US, UK, Euro, Ital, Aus... perhaps a few more too

For anyone wondering what the size of the hole at the end corresponds to, (considering the choke is perhaps not the bore size);

Gauge number (using inch) = 4.66 [divide by] diameter cubed

{to go the other way, diameter from Gauge, d = (third root of ) 4.66/g}

and for those not as au fait with old timer measurements;

Gauge number (using cm) = 76.39 [divide by] diameter cubed

{to go the other way, diameter from Gauge, d = (third root of ) 76.39/g}