Help with injection technique pleeeaase

[getapickle]

I'd like to successfully try the "air-lock" injection technique I've heard about, meaning leaving a very small pocket of air in the syringe so that every last bit of the oil can be injected, rather than having a small amount left in the base of the needle afterwards.

My problem is that when ever I try this I cannot seem to aspirate. No matter how far I pull back the plunger there doesn't seem to be any suction; no more bubbles entering the syringe, no air bubbles moving through the oil. (Doing a standard injection with all the air pushed out of the syringe, I check for bubbles at the the base of the needle as I pull the plunger back. No blood and a few little bubbles mean I'm good to go.) Perhaps I don't understand the physics of this though, beats me. Any help is greatly appreciated!

[bigbench]

You could be adding TOO much air in the syringe. You only want the smallest amount in there. Basically, when you have all the oil in the syringe, you want to suck just enough air to clear that oil from the needle and thats it.

[advanced-stealth]

Stated well.

Originally Posted by bigbench

You could be adding TOO much air in the syringe. You only want the smallest amount in there. Basically, when you have all the oil in the syringe, you want to suck just enough air to clear that oil from the needle and thats it.

[SwollenMick]

My first instinct is to agree with Bigbench. Make sure there is only enough air to clear oil from the needle. Also Because there is air present, the very small bubbles that are easy to see in the oil may be hard to detect because it just adds to the air pocket. I hope that makes sense to you.

As for injection techniques I recently read an article comparing the "air lock" and the "Z track".
A comparison of two depot injection techniques