my question is when I buy powder does the ffg or fffg matter in terms of saftey if my rifle is rated for 120 grains of loose ffg can I use 120 grains of fffg? my concerns are mainly for my fathers sidekick and my omega z5 I know my omega is rated for 150grains loose or pellets and the sidekick is rated for 120 loose and 150 pellets, but in booth manuals says nothing about fffg, what would my restrictions be if any using fffg insted of ffg or can I use the regulations for ffg for the fffg??????