I tried my .22 Diana air rifle on a make shift target

check out the last photo at http://picasaweb.google.com/vineeth.the ... mrE6Q0TqLs#

the specifics are as below,
i shot 22 pellets at the target from 20 feet. i sketched a target on a paper and stuck it to a cardboard sheet. the total width of the target (the one in the pic) would be 1 mm. I nailed this target on a wooden plank 2 inches thick. almost all the pellets passed clean through the target and made a circular embed mark on the wooden plank.
whatever information you can glean from the above are welcome. what i need to know most is can i use this rifle at shooting ranges? Do they permit .22 air rifles ?