I use the GC50 Gel Coat a lot these days. It has taken me a while to get the technique right. I use the EC Gel Coat Gun at 65psi. I lay it down thick in one pass with the Gun approx 18 inches from the Mould. The resulting surface finish is quite "orange peely" to look at in the Mould but once infused the parts come out of the mould like glass, only needing a quick polish to remove the Release Agent from the surface. I must say that I have had very mixed results when I  have used the GC50 on wet layed parts. The biggest headache are "drips" from the gun on the surface if you are not careful. 

Carbon Copies Ltd