This is my review of the Global Defense Initiatives (GDI) MT5-OSM™ (Aimpoint Micro Mount).
I initially heard of GDI while browsing another forum. I have tested every QD mount on the market that I know of so I really wanted to get my hands on one of these to compare it to the others. I sent out an E-Mail and to GDI and I explained to them who I was and asked them if they would be interested in me doing a T&E for their Aimpoint Micro MT5-OSM or MT6-OSM Mount. I was pleasantly surprised when I received an E-Mail from Kate Hagen indicating she would send me the MT5-OSM for T&E.
Description: Sight mount for Aimpoint® Micro T-1, H-1, and R-1 Red Dot reflex sights
P/N: MT6M, MT5M, MT3M, MT1M Materials:
CNC Machined Aerospace Grade Aluminum Stainless Steel
Finish: MIL-SPEC Type III Hardcoat Anodize
Category: Patent Pending
- Adaptable to: Aimpoint® Micro T-1, H-1, and R-1 Red Dot reflex sights
- Zero Retention/Repeatability: .01 MOA
- Adjustable to out-of-spec / worn M1913 Picatinny rails
- Auto-locking Quick Detach™ (ALQD) lever system
- Non-abrading / gouging Picatinny rail lockdown feature
- Lightweight rugged design
- American Made
MT6-OSM™ (Optical Sight Mount) Sight mount for Aimpoint® Micro T-1, H-1, and R-1 Red Dot reflex sights: M4/M16 Compatible • Lower 3rd Co-witness: Front sight post tip in lower 3rd of sight picture.
MT5-OSM™ (Optical Sight Mount) Sight mount for Aimpoint® Micro T-1, H-1, and R-1 Red Dot reflex sights: M4/M16 Compatible • Standard Co-Witness: Front sight post tip in-line w/red dot.
MT3-OSM™ (Optical Sight Mount) Sight mount for Aimpoint® Micro T-1, H-1, and R-1 Red Dot reflex sights: HK416/Gas Piston Upper Compatible • Lower 3rd Co-witness: Front sight post tip in lower 3rd of sight picture.
MT1-OSM™ (Optical Sight Mount) Sight mount for Aimpoint® Micro T-1, H-1, and R-1 Red Dot reflex sights: Low Height Above Bore Weapon Rail Compatible (Shotgun, Subgun, PS90, Pistol, etc.).
When I took the mount out of the box, my first thought was, “this thing is built like a tank.” As I inspected the mount, I noticed the fit and finish was perfect. The mount is hollowed out to reduce weight.
Auto-locking Quick Detach™ (ALQD) lever system:
Overall, this is one of the better QD lever systems I’ve tested. The lever itself is nice and strong. The Auto-locking mechanism is spring loaded and locks down solid. I tried very hard to pull the lever open without moving the Auto-locking mechanism and it would not open. I’ve done that with others and the locking system failed. This is the best locking system I’ve seen on a mount. To adjust the mount, you just need a flat head screwdriver. It doesn’t get any easier than that. Another nice thing is that this mount will not mark/gouge the upper receiver. Not a big deal to some, but a big deal to others.
Mounting the MT5-OSM™ (Optical Sight Mount):
Mounting the MT5-OSM is very straight forward. You just have 4 screws that are mounted through the bottom. The screws that came with my mount had small heads and I did not use any Loctite on them because I was afraid that I may not be able to remove them without stripping the screws. I E-Mailed Kate Hagen and she indicated that they are replacing the screws with screws that have a larger head and a torx drive versus allen. This takes care of my only complaint about the mount.
I went to the range to test out the repeatability of the mount. After my initial zero, I did a couple of 10 round shot groups at 100 yards using a 3xMagnifier behind the T-1. I then removed the optic and placed it back in the same exact slot and shot a couple more 10 round shot groups and repeated 2 more times. There was no noticeable shift in zero, which is consistent with all of the other QD mounts that I’ve tried. That is one of the nice features about QD mounts.
IMHO, this is one of the best QD mounts on the market. It just flat out does what it was designed to do without any frills or gimmicks. I highly recommend this mount on a duty or personally owned rifle.