I draw and shoot with a 25g, no problem. It only takes me a couple minutes to draw with the 25. Have you tried heating up the oil before you draw it out of the vial?
This is what I do:
1. Fill the sink with hot water and place the vial in it.
2. Get all my other stuff ready (needles, alcohol swabs, ect) which takes a few minutes
3. Take the vial from the water, alcohol swab it, flip it upside down and draw out ___CC.
4. Quickly swab my injection area and switch pins
When drawing, just take it slow. I pull the plunger back a few mm, then let it fill. Pull back a little more and let it fill again..... I always get no air bubbles and nice smooth injections.