Is it bad to shoot my gun with the bolt upside down?

[slipknot507gr]

I have a b2k4 and I heard it was more quiet to dryfire this way, but it doesn't really seem like it would be too good for my gun. Is it ok to do, or should I not?

[lotus_esprit5]

it's fine

[coolbluelb]

Only in the southern hemisphere...