Gemtech GM-45/BLKSD Threaded Rear Mount 1/2x28 TPI - High-Performance Suppressor Adapter

The Gemtech GM-45/BLKSD threaded rear mount adapter is a precision suppressor accessory designed to extend the compatibility of your Gemtech GM-45 or Blackside suppressor to fixed-barrel firearms. Built with a 1/2x28 TPI (threads per inch) connection, this rear mount threads directly onto qualifying barrels, allowing you to run one of Gemtech's centerfire suppressors on weapons that don't have the standard front-mount configuration. It's a practical solution for shooters working with platform-specific or less common hosts where conventional mounting isn't an option.

This adapter is engineered for shooters running subsonic ammunition in 300 Blackout, the primary cartridge rated for the GM-45 and Lunar-45 suppressors. Subsonic loads—rounds designed to stay below the sound barrier—are essential for getting the full hearing-safe benefit these cans are tuned for. If you're building a quiet, short-range setup for hunting or training, or retrofitting a fixed-barrel gun into your suppressor ecosystem, this rear mount bridges that gap without requiring barrel work or replacing your host.

Gemtech's modular approach to suppressor mounting means you can maximize your investment across different rifles. Whether you're consolidating gear or adapting an older or specialized firearm to modern suppressor technology, this threaded adapter keeps your options open and your setup flexible.

Key Features

• 1/2x28 TPI threaded connection for secure barrel mounting
• Rear-mount design enables use on fixed-barrel firearms
• Compatible with Gemtech GM-45 and Blackside suppressors
• Rated for 300 Blackout subsonic ammunition
• Expands suppressor compatibility across multiple hosts

Specifications

Thread Pattern	1/2x28 TPI
Suppressor Compatibility	Gemtech GM-45 and Blackside
Rated Cartridge	300 Blackout (subsonic ammunition only)
Mount Type	Rear-mount threaded adapter

Frequently Asked Questions

What firearms can I use this rear mount on?

This adapter threads onto any barrel with 1/2x28 TPI threading, making it compatible with fixed-barrel firearms that accept that standard thread pattern. It's designed for hosts where front-mount suppressor attachment isn't feasible.

Is this threaded rear mount compatible with all Gemtech suppressors?

No. This adapter is rated for use with the Gemtech GM-45 and Blackside suppressors only.

What ammunition should I use with the GM-45 or Blackside suppressor mounted on this rear mount?

The GM-45 and Lunar-45 suppressors are rated for 300 Blackout with subsonic ammunition only. Subsonic rounds are critical to achieving the hearing-safe performance these suppressors are designed for.

Can I mount this adapter on any barrel, or does the barrel need specific preparation?

The barrel must already have 1/2x28 TPI threading. No barrel modification is required if your barrel accepts that standard thread pattern.