Air Arms Owners Club

Hi all

I recently purchased an S510 FAC superlite

Absolutely brilliant gun and very pleased with its amazing accuracy.
It has a Hawke 4-16 5 A0 IR scope
Zeroed at 30 metres and [Yes I know I need more practice to realise full potential] and was achieving 5 grouping in 20 mm.
A squirrel presented at 8 metres and I completely missed, 3 x!!
Put up a target at 8 metres and I was hitting about 75mm below aim point. I would have thought I would have been over rather than under.
Please explain somebody. Thanks

the simple answer is that the center of the barrels bore line is lower than the center of the scopes bore line. you will find that the center of the scope tube to the center of the barrels bore will be close to the distance you have measured. the imaginary lines do cross at some point usually at the sighting distance.
https://en.wikipedia.org/wiki/Rifleman%27s_rule

Thanks, what I still struggle with is ;
The height between bore line and scope line is less than 2' . I can see that at very close range for a sight zeroed at 30 metres the point of impact could be as much as this below target.
But my POI is greater than this by factor of at least x 2 ie about 4.5"
The undershoot I would have thought to have declined to nearer zero as the slug climbed on its trajectory. I would expect it to shoot high at 15- 25 metres and drop by 30 to be accurate at that range.
So how can the slug drop more than the difference between bore and scope lines and still be accurate at 30 metres?

have you used a ballistic calculator such as chairgun? a useful tool. of course sitting and shooting cards at all the ranges from 5m in 5m intervals to your max range.