AEA .30 50gr speed question

Hey guys,

so not having the best luck with the JSB pellets and ordered some AEA .30 50 gr pellets and I am totally new to Airguns and wanted to see what guys are shooting them at speed wise.

Gun Specs:
FX M4 .30 700mm
Stock barrel And internals

Pellet:
AEA diabolo
.30
50.50gr

Not sure what you guys have found is a happy speed for these guys any help would be appreciated