Get some 1 mill syringes. They are small.use .10 of a mill for one gram walk it up from there a.05 if you need too. the oil should barely move when in catridge not at all if its cold. It's very stain specific. Some take .10 some take .15 some more. the less terps the better.just heat oil decarb add terps while still hot stir stir stir and inject into carts. Hold on to the tip of syringes while injecting to keep them from poping off. they can do that when the oil is thick its a bummer .

You will need to winterize the rosin too probly.it ls usually to waxy and fatty to flow through carts.