changing string gauge by self?

[Gunstringer]

im a drop player, i play pretty low and i like my strings really tight, so i am moving from 50-110 to 55-115. plz dont tell me go 5-strings, i just want to know what does it take to setup ur guitar to a new strings gauge.

[joebar]

you will need to adjust the bridge saddles (intonation) whenever you change the gauge of strings or whenever you raise / lower the action.
you may also have to modify the nut to accomodate a larger E string; it depends...

[Rick Auricchio]

And it may be necessary to adjust the truss rod.

Given the amount of possible adjustment and change, you might be safer having a luthier do the job. Then you don't risk ruining the nut if it needs changes.

[Gunstringer]

is the nut only need modifying in the E string slot? the other strings doesnt need modification?

[joebar]

you may want to take it to a qualified luthier because there are several factors.
the other slots in the nut may need filing as well, but the e string is the one that is above what would be considered a standard sized slot. the nut is critical to how the bass will ultimately play. because the nut is non adjustable, it needs to adjusted perfectly for optimum playability and intonation in the first few frets.