Nelly -- I Don't Hate Floyd Mayweather ... Even If My GF Does

His GF claims Floyd Mayweather pulled a gun on her ... and repeatedly beat her up ... but Nelly says HE'S not going to bury the hatchet with the boxer because "I ain't got no hatchet to bury."

It's an interesting statement ... considering Nelly's girlfriend Shantel Jackson filed a bombshell lawsuit against Mayweather earlier this year ... essentially saying Floyd terrorized her during their 2-year relationship.

Floyd and Nelly have also exchanged barbs in the media -- but last night, when Nelly was leaving Pinz bowling alley in L.A., the rapper insisted he's not the one holding the grudge.