As long as a MP5 is semi-auto and has a 16" barrel it is legal in MOST (not all of course) states. Some states require magazines that hold no more than 10 rounds of ammunition.

I typically keep 9 loaded 30 round magazines for my AR-15 and 270 rounds extra 5.56x45mm. I keep 5 of my 10 magzines for my Sig P220 and 100rnds of extra .45acp., 200 rounds of 9mm, 1000 rounds of .22LR (it is dirt cheap) and for the 12g I keep 100rnds of #7 birdshot, 25 1oz Slugs, 25 OO buck, and 50 #4 Buck Shoot.

skoolkid: your own version of grammar makes reading your post extremely painful. If you would like to be taken seriously here I would advise you dump the gutter speak.