^ what the fuck are you teaching these kids?! do not....use a 18 gauge pin to inject! it really bugs me when people dont realize what they are doing and teach people the wrong things. you will be fine with a 23 g pin. let me explain why.
depending who made your suspension will dictate how large the test crystals are, thats why you are having trouble pulling the test into the syringe. ALSO! the brand of syringe will make a big difference...ive always sweared on bd, but not for water based test, buy Terumo those 23g v.s. a bd 23 are waaaaaaaaaay better,if you dont feel like getting a 18g pin to with draw the test and your still having issues getting it out, follow these directions...
inset needle into the vial (assuming its a 10ml vial)
inject air into vial (.5cc or what ever your dose is gunna be)
pull plunger to remove test.
if test is not coming out or is barley trickling out, then pull plunger back to the max out zone, release and let it snap back, repeat that about 8-10 times (or how ever long you need untill you get the desired test out)
change needles
point needle down, pull back on plunger slowly allowing air bubbles to mix the suspension in the syringe.
and enjoy.
.....if your not a injection ninja and you go to slow the cyrstals will harden and make wall in the needle. to help prevent that, also ad .5cc-1cc of a b vitamin i prefer b complex over b 12...but either one is fine.