If it is only a year since you sowed the seed and you have a good potfull, then, well done, you have done well. It will be several years before these immature bulbs become flowering size and they will need a little attention in between.
If you think that they are already root bound then you probably sowed the seeds rather thickly and they will now need potting on into a larger pot. But don't try pricking out individual seedlings as you would with herbacious perennials. Whilst the seedlings are in good growth take a slightly larger pot, put a little fresh compost in the base of it then, holding your breath, knock out the whole of the original pot of seedlings, compost ball and all, and quickly drop it into the new pot. Fill the void spaces with new compost and allow the seedlings to grow on.
You can leave the Colchicum seedling pot outside in a sheltered spot and you may have to pot on once again in a few years time.
Good luck, Don, and look forward to a fine display.

Many thanks for your information on growing my Colchicums from seed. I have already pricked them out and got about 60 pots,does this fact mean the plant will suffer,they do seem quite healthy. However the time you say it is going to require for them to form the bulb makes me wonder if I will complete this task,I turned 80 this year but I will keep my fingers crossed. Thanks again, Don.

Well now Don, there's an excellent incentive for many more happy years gardening. Best wishes for a very satisfying outcome to all your work.

I grow lots of bulbs from seed, Don; there is a clue in my choice of user name! I try not to pot the seedlings on at all, if possible, until they have a first flower, but feed them in the pot.. Sometimes the pots get overcrowded and then I pot on as described above. It is a process that requires a little patience, think of the size of a Naked Lady bulb, but very rewarding.