sub .12 ft/lb .22 Garfield.
@ pianoman, what's the retained energy in sub 12ftlb at 100yrd's and what cal are you using? http://www.thehuntinglife.com/forums/pub...
I don't know what the retained kinetic energy is at these ranges but, it's plenty more than enough as the shot hits from a plunging angle and gravity takes an effect. A chrono and balistic putty will give an accurate measure. I've never measured it with a .22 air rifle pellet but done plenty of calibre-effect testing with .300, .303, .308 7.62mm and .50 ammunition in extreme range shooting during my service years. A hit from a plunging round carries far more destructive kinetic power than the same calibre round hitting from shorter ranges using flatter trajectories. Taking this as a principle I've only really scratched the surface of applying it to air rifle shooting.
I think air rifle arms manufacturers have the technological means to produce far more efficient pellets, barrels and cylinders for a next-generation of air rifle that will enable a degree of greater range accuracy control by more skilled shooters more consistently. But it would mean perhaps charging prices into several thousands of pounds and that's just not financially viable. Not when an FAC and a good .22 or .17HMR rimfire can be bought for a few hundred pounds.
As things stand, I've found 12ft/lb air rifles and pellets in both major calibres now, are capable but, I must stress, ARE NOT CONSISTENTLY capable, of accurate field shooting to 200 yards. If they got those inconsistencies ironed out, it could be amazing what the humble old air rifle's performance could be made capable of.
The main problem however is that the average 11.5 ft/lb output at the muszzle is not enough to counter variances in the wind. You need absolutely not a breath of wind when shooting a target at these extremes.