The only time I hit a vein was with peptides. Only shot about 10-20 units and it left a huge painful bump right after and a giant bruise that lasted a couple weeks. I'm sure I just had bad luck with that shot, but water seems to be much more painful when going IM for me.
Nice guys. Thanks for all the responses. Ill be using slins in my chest. Going to have to work courage up to just slam that slin pin in there. Is it better to go slowly or just push it in? If i go slow at least i could feel if i nick somethinv