Hyve Technologies +2 mag extension for Shield 9mm, along with Magguts follower +1, range test, tl;dr works fine.

I have Magguts follower systems in all 3 of my Shield carry magazines, one std and 2 extended. In the pistol I use the standard mag due to how it carries, with a Pearce pinky extension. Std 7 rds +1 is 8, +1 in the chamber, so 9 in the pistol.A second mag is in my Tactipac Elite holster, the Shield extended version 8 rd. So, with Magguts its 9 rds. I usually carry a 3rd mag of the same type in my pocket in a Sneaky Pete sleeve. The reason is I've found through exercises at our outdoor range, sometimes I can access the one in the holster better, or the one in the pocket, depending on body position at the moment.Magguts had no knowledge about their product combined with the +2 Hyve extension. They hadn't tried it, didn't know if it would work or not. Being an overly curious type, I decided to do the test myself.So, I recently got one of the Hyve +2 extensions. Combining with the Magguts +1, now it's a +3 magazine. It does make the grip longer, but I only will use that on my backup magazine. The carry one will continue to be the standard w/Magguts. That gives me 8+1 carried, and 11 in backup, for total 20 rounds available with one mag change. Way more than would realistically be needed for a self defense application.First, I used a load machine in my lab to verify the force on the last round, at 9mm deflection of the follower (like would be placed on the last round). I figured if it's going to have a problem, it would likely be due to not enough spring pressure to feed the last round properly. In fact, with an extended mag, just adding the Hyve +2 reduces the standard spring's force on the last round by 22%. Adding the Magguts follower further lowers the force, for a total reduction of 32%. Still enough to feed ok? Dunno....So, I tried it out at the range today. I loaded 2-3 rounds at a time, firing to slide lock. It locked back every time, in about 12 trials. It fed fine with the full 11 rounds, too. Tried it with my carry ammo too (Federal HST), with the same positive results. Slow fire, rapid fire, ok. Practicing a mag draw from my holster and rapid fire, two times it didn't lock the slide back. Sometimes that happens with my thumb riding the slide lock with any mag, and I may have done that. Just not sure if that's any fault of the mag. And even if this mag didn't lock back, it's not a big deal since it's my backup mag anyway. If I've run through 20 rounds to slide lock, I may have bigger problems. And, I don't think it's a real issue.YMMV, but I'm going to carry this magazine in this configuration.tl;dr In a Shield 9mm extended mag, the Hyve Technologies +2 mag extension works well with the Magguts +1 follower system. It is indeed possible to have an 11 round magazine for a Shield. via /r/CCW http://ift.tt/2elfRWj