Syringes (without the needle!) are really useful for filling tubes and other types of packaging with small openings. I use them mostly for getting lotions into soft squeeze tubes. They “steer” a lot more easily than piping bags, and you have a lot more control than you do when using a funnel.
I recommend purchasing something that’s about the same size as the containers you’ll be filling. I usually make 100g (3.5oz) batches of lotions, so it would be nice if my syringe would easily hold the entire batch. The ones I have at the moment don’t, and that’s a bit of a pain.
You can find syringes like this under the name “catheter syringe” on Amazon. Another possible option is a “meat injector syringe“, though you’ll want a fairly wide injector bit as our lotions are a lot thicker than meat juices.
If you’re finding the plunger starts to be hard to push down as the syringe ages, try swapping out the rubber gasket (or the entire plunger). I’ve found they tend to deform and swell after multiple washes.
Check out these videos to see a syringe in use for tips & tricks:
