[xsrdx]

Do any of you marksmen think it possible for a man to place 20 shots in a 20-inch circle in 20 seconds at a 1,000 yards?

Exceedingly difficult, but no doubt possible.

20rd mag, semiauto.

A 338 Lapau or 50BMG would likely be more precise, but slower; and mag capacity would be an issue.

Maybe a belt fed platform?

NRA Highpower spec AR's, the AR10T, and SR25 seem a likely starting point, with a 20rd mag and good optics.

[xsrdx]

Lapau=Lapua

[Travis McGee]

I agree, it will most likely be a box fed medium caliber gas gun from .243 to 308 that wins the Cooper Challenge, if anyone can do it.

With great optics, a free floating bull barrel, a great trigger, well supported on sandbags, a fantastic shooter....I think it can be done.