Do i need primer to glue PVC?

[o_0 highflyin]

so on the weekend i made a potato cannon [spud gun] and i took pvc glue and glued it all together and today i was watching how to make one and it say put primer and then glue [ IS IT BAD WILL IT HOLD TOGETHER]

 

[Oldwhiteguy2earth]

Primer is essential for use as water pipe. Projects can be assembled without primer. Not sure how much pressure a spud gun has.