Cain Arms Glock Magazine Extension Initial Review — 3D Printing Perfected?
Over the last month, I have been testing the Cain Arms Glock Magazine +6 Extension. I had my first conversation with David Cain, owner of Cain Arms, in the beginning of February, 2017. I was curious about his ability to offer mag extensions so at such an affordable price. He let me know that he had come up with a great design and that 3D printing had made the market available to his company at a reasonable price for everyone.
Shortly after our first conversation a package arrived. I thought it would be a testing model. What David sent me were three different magazine extensions, in three different colors. He also included an AR15 angled foregrip he has designed. I was not expecting that at all. Generally when we receive a product for testing it is one of the exact item we had discussed, so huge cudos to David.
I looked them over. Carefully. If you go back and look at any of the videos from Cody Wilson and what he was trying to accomplish when he first started printing AR15 lowers from the files available on his Defense Distributed web site, you’ll see why “back in the day” there might have been some trepidation. Since that time, 3D printing materials and processes have gotten a lot better. I was imagining the bottom flying off under a full load on 21 rounds. Thankfully that isn’t even close to an issue.
What struck me first was the shininess of the 3D printing. I hadn’t expected that. I have seen and handled a lot of 3D printed objects, mostly curiosities, and the material always seemed dull. However, the 3D pieces from Cain Arms have a very nice texture and look. They have the company logo printed, or rather, un-printed (my fancy-ass word for negative boolean space) on the side. Nice touch.
On their web site they have several videos, one of which is the instructions on installing the extensions:
If you have ever disassembled a Glock magazine you know it can be a pain in the rear to remove the base plates because of those tabs on either side. Do away with them! They are annoying. Most of the base plates we have tested have you do the same thing.
Over the course of testing, I was surprised more and more with the fit and finish. I did however run into one snag. In the video you can see that you can run the magazine extensions without the inner floor plate to get the maximum capacity from the extension. Stretching the spring is offered as a solution. However, while removing the inner plate allows you to add plus 6 to your total carry, I was having an issue with the slide not returning fully to battery on the last round. This was remedied by purchasing heavier/stiffer magazine springs. Now the magazines feed flawlessly up through 21 rounds.
I will have a complete review after spending more time with the Cain Arms extensions and a comparison with several other brands. As for this first round of testing they have proven to be extremely durable, a great fit and a perfect compliment to our project Glock 19. The extra capacity makes trips to the range that much more fun.