I love the A2 Front Tower sight look (if thats the correct description for the typical M16/M4 triangle front sight) ...so I think I will buy one and just slap it on the barrel. Well that's what I am hoping... does it need gunsmithing since there is no gas tube, ie can it just be bolted on?

There seems to be various diameters..will these fit the MP15-22 barrel? What size should I get?

And any recommendations as to where to get them? I pretty much buy all my stuff at midwayusa.com.

Thanks for any help/advice you may have....