Good afternoon everyone and thanks for tuning in for another addition of Silencer Saturday brought to you by Yankee Hill Machine, manufacturers of the YHM R9 suppressor. Last week we went all apocalyptic prepper on you by testing out an oil filter suppressor and mount adapter – not great, not terrible. This week we get an in-depth look at the new Griffin Armament GP-N (GP-NATO) A2 birdcage mount suppressor. Is it worth returning to your retro roots? Let’s take a look.
Many thanks to the guys at Griffin for asking us to review the GP-N and shipping it out so quickly.
Griffin Armament @ TFB
The A2 Birdcage Flash Hider
If muzzle devices were musicians, the A2 flash hider would be The Beatles – the most recognizable, the most popular and the most universally loved flash hiders in history. Sure you may think The Beatles are outdated and annoying, but you still have a few songs tucked away on your phone for nostalgia. Plus, chances are if you’ve bought a complete AR-15 rifle or upper receiver in your lifetime, it probably came equipped with an A2 birdcage flash hider.
But, technology, testing and manufacturing techniques have developed some very effective flash hiders and muzzle brakes from companies like SureFire, YHM, Dead Air, Griffin and others. With all these excellent choices available, why should we care about a 50+ year old flash hider that was never designed to be a suppressor mount in the first place.
- Cost: Suppressor muzzle devices can run as high as $150 and the attachment system (if your silencer only came with a direct thread module) can add another $200 to the overall cost.
- Availability: If you don’t already have a few stashed away in a parts bin, finding an A2 flash hider at Brownells or another parts supplier for around $10 should be easy.
- Standardization: Law enforcement and other organizations have rules about weapon modifications that may prevent the use of certain muzzle devices. Adding the Griffin Armament GP-N to the armory is about as easy at it gets.
As with any type of firearm upgrade, there are a few trade offs for adding “universal” capabilities.
- Length and weight: Attaching a suppressor to a muzzle device that was not designed to be a mount as its primary function will mean some additional material and space to allow the mechanism to function. The GP-N adds about five ounces and a little more than an inch in length. Definitely not a dealbreaker.
- Crush washer replacement: I’m willing to bet that 99% of all A2 flash hiders on AR-15 style rifles use a crush washer to properly time the vents/porting on the barrel. Unfortunately, crush washers can be a killer of suppressors. Flat shims are required to properly mount the A2 birdcage and insure that the barrel bore lines up concentric to the suppressor bore.
- Compatibility: The GP-N is meant for A2 style flash hiders with the collar/mount machined directly into the silencer body. The result is a solid system, but one that is limited to only a few muzzle device options. Griffin does make an A2 mount adapter for the unofficial industry standard suppressor mount threads of 1.375 x 24 if you decide to add A2 functionality to your favorite can.
Griffin Armament 1.375 x 24 suppressor A2 mount adapter:
Griffin Armament GP-N – Long Live The Birdcage!
Griffin’s GP-N™ (GP-NATO) suppressor is a robust, dedicated 5.56mm suppressor which provides secure fitment to common A2 compensator. The A2 compensator is a familiar muzzle device to nearly all AR15 rifle owners. This simple, inexpensive, yet effective compensator has served the military for decades. The Griffin GP-N™ was designed to bring modern suppressor technology to the A2 mountable class of silencers which started in the late 90’s with the Gemtech® Halo.
Fully machined from 17-4 stainless steel, the GP-N™ offers users with an extremely durable welded general-purpose suppressor. Full H900 heat treatment further increases strength and service life to the product. The mounting collar is QPQ nitrided and the suppressor is spray coated in Cerakote® to provide a smooth, heat resistant, and desirable finish.
Cutting edge materials and composition aren’t the only upgrades to this suppressor. Griffin’s ECO-FLO™ baffles provide substantial blow-back reduction on semi-automatic systems while balancing sound pressure levels at the shooters’ ear and the muzzle to optimize sound performance.
Attachment to the host firearm is simple, quick, and secure. Included wrenches and interfacing geometry ensure rock solid mounting security that you can trust. The GP-N™️ suppressor’s premium material composition, ECO-FLO™ baffles, and 16oz mass ensures that full auto fire is well within its performance limitations.
The Griffin GP-N™️ is a modern A2 flash hider compatible suppressor, inspired by a legend, and built on years of dedicated research and development.
- 745.00 MSRP
- $675 @ Silencer Shop (price varies by dealer)
- Manufacturer’s Page: Griffin GP-NATO
- A2 Collar Mount machined into tube body for ultimate strength and precision
- ½” shim set included
- Wrenches included
- Full 17-4 H900 Heat treated stainless steel
- ECO-FLO™ baffle system provides market leading suppression
- Cerakote Finish resists heat and abrasion
- Fits most 22mm NATO A1/A2 flash hider & Griffin’s Gate-LOK Hammer Comp
- 1.5” diameter – 6.5”length
- 16oz weight including mount collar and shims
- Rated for all .22 caliber cartridges
- Full Auto Rated for 5.56mm down to 7.5”
Griffin Armament – Griffin’s GP-NATO™ suppressor is a robust, dedicated 5.56mm suppressor which provides secure fitment to common A2 compensator. The A2 compensator is a familiar muzzle device to nearly all AR15 rifle owners. This simple, inexpensive, yet effective compensator has served the military for decades. The Griffin GP-NATO™ was designed to bring modern suppressor technology to the A2 mountable class of silencers which started in the late 90’s with the Gemtech® Halo.
Griffin Armament – Evan demonstrates how to install and provides maintenance information for the GP-Nato, a dedicated 5.56mm suppressor from Griffin Armament.
A2 Birdcage Flash Hider Installation:
I am not going to go into the details of swapping out the crush washer for flat shims. Make sure to follow any manufacturers guidelines, watch the above video and seek out the assistance of a qualified gunsmith if you get in over your head. With the proper tools, this step should take about 10 minutes.
Mounting the GP-N is a simple three step process.
1. Unscrew the locking collar from the suppressor.
2. Slip the locking collar over the flash hider and fit the narrow edge into the second groove (closest to the barrel shoulder).
3. Screw in the GP-N onto the locking collar, making sure the narrow edge remains in the groove. Use the included wrenches to tighten everything up. Test for concentricity using a guide rod or other device.
Shooting The Griffin Armament GP-N
The GP-N is listed as being full auto rated down to 7.5” barrels, so after a few test shots, I went right into two 30 round mag dumps. Everything stayed locked up nice and tight. Reminder, if you are going to touch a suppressor after more than a round or two of fire, make sure to use heat resistant protective gloves. The GP-N was smoking hot.
As for the sound reduction, the GP-N was quieter than I expected for a Kurz-ish sized silencer. It’s not “damn that’s silent” but it’s also not “f*ck your ears” loud. My guess is that it will meet and exceed your expectations for a 6.5” suppressor. It’s a centerfire rifle suppressor, so wear your hearing protection.
I have always been biased against the A2 mounting styles on the market – old tech that has been supplanted by new solutions, especially over the last 10 years. But I also never spent much time behind one, especially for full auto use. The Griffin Armament GP-N is an elegant solution for a classic design. If you are a fan of the A2 flash hider or are bound by policy to use it, the GP-N is an excellent option that can withstand heavy use. The street price is more than fair for what you get and it performs better than similar-sized silencers.
If the birdcage is your thing, these benefits outweigh the detractors and the GP-N should be on your list for consideration.
Thanks for reading. Be safe, have fun and we’ll see you back here next weekend for another Silencer Saturday.
Silencer Saturday is Sponsored by Yankee Hill Machine