Don't do it, abdominal muscles aren't thick enough to be sure you're in muscle. You'll likely either go too shallow and end up with a lump in the sub-q fat, or worse, go too deep and go THROUGH your ab muscle and the parietal layer of your abdominal cavity. Squirting test/tren into your actual organ space is NOT a good idea. I'd shoot anywhere before abs... traps, forearms, between the toes... you get the point. Only thing you shoot in the abs is sub-q stuff like GH/slin/IGF/HCG.