Texture can be varied depending on how big the holes are in the sponge. A sea sponge can leave some huge peaks and they are all sanded before being painted. I also do glocks and use a smaller pattern sponge, I leave the front strap pretty rough and really knock down the sides.
Just make sure to use the right epoxy. The Devcon in a tube at the hardware store or JB weld will not work, they lay down and dont keep the spikes before it hardens up.
Glock in progress after sponging, easy to see how "spiky" it would be. This little spikes are very hard and will cut you before sanding.
Finished product knocked down.