If you choose to do something like this MAKE SURE YOUR GUN IS UNLOADED!!!!!!!!
Since this is the first time I have tried anything like this I did it on an old Glock that is one of my beater guns.
Before starting you should practice on something you don't care about. I used an old AR15 grip and a Glock magazine loader that I am never going to use for anything else. As you practice you can try different patterns and see what you like. It's also a good time to see if the pattern you like gives you the amount of grip that you want. You can see my practice grip below.
I guess this is a good time to discuss what you will need to stipple a Glock or any other plastic item. You have to have something hot to melt the plastic with. Some people will use a Dremel instead but that removes plastic and that's not something I want to do. For this project I used an old wood burning tool that my wife bought years and years ago but never used. The tip that came with the tool was fine but if you want more variety or other patterns you have to get creative. I went to the hardware store and purchased brass screws that have the same thread pitch as the original tip. I then used files and sandpaper to create different points. Then it is a simple matter of screwing them in and stippling away. Once again I cannot stress how important it is to practice first before starting on your gun or other expensive item. Below you can see the wood burning tool and the various tips. You may also want a few sheets of sandpaper in various grits.
Ok on to actually stippling the gun itself. This is the part that takes guts. The first step is scary but after that it really isn't that bad. MAKE SURE THE GUN IS UNLOADED!!!!!!!!!!!!!! The last thing you want to do is become a gun injury or death statistic. Double and triple check your gun!!!!!!!!!!!
First I smoothed out the texture that was already present on the grip. I used the flat part of one of the tips to smooth everything out. This should help make the final stipple look more consistent. I sanded the grip slightly, but when I do this again I probably won't sand. I think it was a waste of time. I smoothed the the front and back of the grip. I also knocked off the edges of the side grip texture.
One thing I forgot to mention until now is be super careful. You will be working with very hot and possibly sharp objects. Make sure you keep them out of and off yourself and others. I say this from experience. I managed to cut myself with one of the tips. The up side is that it was hot and cauterized the cut while it was happening.
You need to make sure you have a plan before you start melting everything in your path. Some people lay out the gun using masking tape or markers. You can also just free hand it like I did. Either way you choose make sure you have a plan. Don't just start blindingly melting stuff. I would grip the gun and study my grip to see the contact points between my hand and the gun. That way I could tell where to texture for the most gain in grip.
I find that my reaction hand thumb hits the frame of the gun just above and in front of the trigger guard. I textured that area to provide a reference point for my thumb.
I try to grip the gun very high so I started on the side of the grip near the top of the frame.
From there it is just a matter of filling in the rest of the grip with texture.
I made sure not to go too high on the back of the grip. If you texture the grip all the way up it can rub the web of you hand raw.
While I admit that this is not the prettiest stippling job I have seen, I am happy with the way it turned out. I am a form follows function believer. I would rather have an ugly gun that fulfills a specific need than a pretty gun that is less capable. That is what this gun has become. It is an ugly gun that is more usable now than it was before the stippling. The stippling adds a ton of grip to the gun. Before I began this process I didn't think stippling would make that much of a difference. Boy was I wrong. The difference is dramatic. I plan on stippling more of my Glocks in the future.