There are a few different approaches you could take to making rubber gun grips, depending on what materials and tools you have available. One option would be to cast the grips using moldable rubber material, such as silicone. You could create a two-part mold using materials like Plywood, MDF, or even cardboard, and then pour the rubber into the mold and let it set. Once it’s set, you can remove the grips from the mold and they’re ready to use.
Another approach would be to sculpt the grips out of a block of rubber. This would require some carving skills, but it would allow for a lot of creativity in terms of shape and design. You could use any type of rubber for this, but a softer material like silicone would be easier to work with.
If you’re looking for an easier option, you could also buy pre-made rubber gun grips that are ready to use. These are typically made from a harder rubber material, so they’re not as easy to customize, but they’re still a viable option if you don’t want to make your own.