One of the unique feature of Allen Engineering suppressors is the use of the 2-point mounting system. As the suppressor threads onto the muzzle or muzzle device the rear of the suppressor will push up against a taper and aligns itself. This is why AE boast a zero POI shift when removing and adding our suppressors.
There are also many other benefits. For example, since AE suppressors mount to the muzzle and a taper further down the barrel this helps reinforce the barrel to help prevent barrel whip. This will help tighten your groupings.
The one issue with getting this extremely beneficial system to work is that it requires the collar to be properly fitted to the barrel. The collar is a tapered sleeve mounted on the barrel that acts as a second point of contact to mount the suppressor. AE suppressors index against the taper on the collar to align and secure itself. You cannot use an AE suppressor without using a collar.
The difficulty is that there are many different barrel manufacturers who make a wide variety of barrel styles/profiles, all with ranging tolerances. You cannot just throw and random collar onto a random barrel, they need to be matched together for proper fitment.
Here is the list of collar options so you can find a solution to best fit your needs.
SPR Collar
The most traditionally collar commonly used with marksman rifles. The SPR collar is a sleeve that is mounted by pushing against a step in the barrel and secured with a set screw.
Mod 0: This collar is primarily used on MK12 Mod 0 rifles. It is slightly shorter than the Mod 1 collar. It is designed to be used on MK12 profile barrels.
Mod 1: This collar is primarily used on MK12 Mod 1, Mod Holland, and NSW Recce rifles. It is slightly longer than the Mod 0 collar. It is designed to be used on MK12 profile barrels.
A to B Adapter: This collar is designed to allow B-mount suppressors (AEM2, 3, 4) to be used on MK12 profiled barrels.
Barrel Specific: We are expanding our selection of SPR collars to fit on commonly uses barrels such as Criterion and Daniel Defense. Please click here to see out list of currently manufactured collars.
Custom: Since SPR collars require a specific barrel profile for proper mounting, many competent gunsmiths will make custom collars to fit unique rifle builds. Please click here to see our list of recommended gunsmiths.
PLEASE NOTE: The Mod 0 and Mod 1 collars are functionally the same and can be used interchangeably.
3-Piece Collar
The 3-piece collar is used when mounting an AE suppressor to an AR with a front sight block. An inner sleeve with a taper is mounted to the barrel and secured with an outer donut that indexes with the FSB.
Long: This collar is primarily used to mount the M4 suppressor on a 14.5″ FSB barrel. While there were many early M4 collars used, the 3-piece long collar became the primary design used to mount AE suppressors on FSB rifles.
Short: This collar is primarily used to mount an AEM5 on a 12.5″ FSB barrel. This shorter design became prominent due to the scarcity of M4 suppressors. Please click here for the history of this suppressor/collar combination.
PLEASE NOTE: We manufacture the inner sleeves to fit on barrels ranging in diameter from .719-.745 in iterations of .001.
Gasblock Collar
These add the taper traditionally found on the collar onto your gasblock. By combining these two parts, the gasblock collar provides the shortest possible configuration to mount your AE suppressor. Although, this option does sometimes require custom barrel lengths for proper mounting. Here are the manufactures currently making gasblock collars.
Allegheny Arms: This manufacturer/gunsmith has been working with the AE ecosystem for quite a while. He designed a lightweight low profile gasblock collar. A few of his gasblocks can be used with factory barrel length and B-mount AE suppressors. Please click here for our product highlight on the AA gasblocks.
SR25 Cartel: This manufacturer primarily works on making aftermarket SR25 parts. He recently designed gasblock collars that replicates the style of SR25/M110 gasblocks but can be used with AE suppressors such as the M24 and AEM5-30.
Profiled Barrel
This option forgoes the need to mount a collar to the barrel and instead profiles the taper into the barrel. This is only possibly with barrels that are .9″ or larger in diameter. Thus it is traditionally used with bolt action rifles and can be seen on the M24A2 and M24A3.
CanSOF Collar
Short for Canadian Special Operation Forces, CanSOF had a series of rifles that used the AEM3 (15th Model). The collars used on these rifles are longer than usual and are often confused with being one piece with the muzzle device. These collars are not common and are not typically used.
CQB: Used on the C8 CQB and L119A2 CQB. This collar requires the removal of the bayonet lug on FSBs.
Simon Sleeve: Used on the C8 SFW, the Simon Sleeve was originally used to help mount the M203 to barrels. It was later repurposed and given a taper so it could mount OPS/AE suppressors.
PLEASE NOTE: We currently do not manufacture any version of CanSOF collars. We are in the process of developing them.
| BUILD | SUPPRESSOR | COLLAR |
| MK12 MOD 0 | AEM5 | SPR (Mod 0) |
| MK12 MOD 1 | AEM5 | SPR (Mod 1) |
| MK12 MOD H | AEM5 | SPR (Mod 1) |
| Ranger Carbine | M4 | 3-Piece (Long) |
| Gordon Carbine | M4 | 3-Piece (Long) |
| Gordon Carbine | AEM5 | 3-Piece (Short) |
| NSW Recce | AEM5 | SPR (Mod 1) |
| 416 Recce | AEM5 | SPR |
| M24A2 | M24 | Profiled Barrel |
| M24A3 | M24 | Profiled Barrel |
| C8 CQB | AEM3 | CanSOF |
| C8 SFW | AEM3 | Simon Sleeve |
| L119A2 | AEM3 | CanSOF |
The Real Person!
The Real Person!
I have an AR with a 20” mil spec barrel and want to fit an AEM5 on it and was wondering what kind of collar/mounting hardware I would need to fit it securely on my rifle