GO:0035642

Catalysis of the reaction: S-adenosyl-L-methionine + (histone H3)-arginine (position 17) = S-adenosyl-L-homocysteine + (histone H3)-N-methyl-arginine (position 17). This reaction is the addition of a methyl group to arginine at position 17 of histone H3. [GOC:sp, PMID:11341840]