Hit Chance is slightly based on your PE, a Laser Rifle has got the Long Range perk, which yields a +(PE-2)*16% Hit Chance. If you're gonna lower your PE to 7 while keeping ST at 1, you'll have to get a ST above 1 from drugs (or take Weapon Handling).
I am too lazy to calculate on this right now, but i'm telling you this, keep in mind that 'Weapon Requirement' simply means that you'll get a -20% bonus for each point of ST missing to use the weapon (it will not necessarily be rendered unusable, depending on your PE and Weapon Skill).
As i remember, my Laser Rifle build had a ~60% Hit Chance at 47 Hexes with 300%EW, 8PE and 1ST. I accomodated this by using buffout, now i require an Agility implant to get 12AP instead of 11AP.