Drill bit size for plug spawn

Hi all. I have plug spawn that says they requires an 8.5mm drill bit. I have a drill bit that's designed for plug spawn (drills to right depth) but it's 9.2mm. I tested drilling with the 9.2mm and hammering one in and it seems snug enough. So do you guys think I'll be fine with the drill bit I have or is that a bad idea?

Your drill size should be fine. If there's a bit of space left between the two, then use some soaked wood shavings (that's what I would do)

Thank you!