Someone told me that you could put raw rose hips in a food mill to extract the pulp from the seeds. It didn't work out so well for me--the flesh was just too stuck to the seeds. Maybe it would work in a motorized juicer.
So, instead I stewed the rose hips in water for a long time and strained them through a jelly bag. I cooked some sugar into the liquid to make rose hip syrup. I put the now cooked seed-pulp through our food mill (thanks Davey for giving it up!) and was able to get about half a cup of pulp out. I combined with an equal amount of honey to make this delicious jam. I'm keeping it in the freezer because the water content might be too high to safely leave out as you would with honey. Luckily, it doesn't freeze solid, so it is convenient to pull out to spread on spent grain bread. Technically, this still contains the irritating hairs that surround the seeds, but they've been cooked so much they haven't bothered me yet. The cooked berries have long been used in native cooking, in soups and stews, as well as a dinner vegetable, served with butter and salt.
The pulpy seeds that were left in the food mill looked like they would be good for some more flavor, so I stewed and strained them again and boiled with sugar to make another syrup. This second one came out pretty thick...almost like candy.