I like AA's in my S400 and Accupels in my BSA High power.
If you choose other please tell us all what it is .
Thought this would be a good poll to get going.
Here is an extract from a review done by Ian Pellant. It would seem that a lightweight pellet, or loose fitting pellet, is likely to do damage, rather than a heavyweight in a magnum springer.......Originally Posted by guido
My "rules" / suggestions for selecting pellets for a magnum spring airgun are:
Don't use cheap, poorly formed and sized pellets - they are a false economy!
Don't use pellets that are a loose fit for your gun - they can cause premature piston and spring failure!
If your new spring gun has harsh and noisy recoil, you may have a pellet fit problem. Try some other brand of pellet and do some chronograph testing before blaming the gun or it's lubrication.
Pellets that perform well in pneumatics may not perform well in spring guns; whereas pellets that perform well in spring guns may perform equally well in bolt action pneumatics.
Sizing pellets for magnum spring airguns generally may cause energy loss and is not recommended; whereas sizing for spring pistols and match spring guns may yield more energy and consistency.
Pellets that work well in a spring pistol may not work well in a spring rifle, and vice versa.
Tend towards the heavier pellets in 0.177" for outdoor use (Field Target and Hunting); mid weight pellets for indoor and calm outdoor paper punching.
Be careful when testing ultra light pellets in a very high powered spring airgun - they may be inefficient, or worse yet, not offer sufficient inertia to cushion the piston, you may damage your gun.
Test a variety of brands and styles until you find what works well with your airgun and terminal ballistic needs. Pellet head design plays a large part in energy transfer to the target. High energy does not mean high accuracy. A wide variation in shot string velocities will yield inconsistent energy and poor accuracy.
Buy a good selection of pellets and test, test, test!