Hi Robbie
This subject has been covered previously if you do a search you can probably find it. I've just had a quick look and can't. 
I think Alex started the thread 
You don't need to buy "delrin", it's just a brand name for an acetal homopolymer mix manufactured by DuPont and there are several other very similar brands available, however it isn't truly non stick and very few thermoplastics are. The nearest you'll get is PTFE but polypropylene, acrylic, polycarbonate and nylon in any grade work well also and apply a little wax on any of them and problem solved.
The better solution however is cones as they allow you to seal the blank ends and they are dead easy to make, I have several pairs, my first were made from scraps of acrylic pen blank and are still going strong. Alloy or brass will work as well if you're happy to turn it.
I'm lucky in that I used to work in the semi finished plastics industry many years ago so I still have an amount of scrap in several materials, if you want to try some out drop me a pm.
