seem low to me also as there are warnings of one mile with regular 22 bullets.
There’s a difference between “accurate” and “harmful”. The former is the ability to pierce a mellon deliberately from a mile, the latter is the potential to pierce a mellon that happens to be wherever the bullet comes down.
That's "max effective Range", meaning the range at which one could expect a well trained shooter to hit a man sized target. However the maximum range that the bullet can reach, and cause damage should it hit anything is much longer. So yes a .22 can reach a mile or mile and a half, but this thing should reach much farther, but you could not do any more than harassing or "ranging" fire. With an automatic weapon, that can still be quite effective, but with low capacity bolt or semiautomatic it would be no more than harassment.