Ive recently seen people get confused between the AEM4 and the M4. This is due to the two suppressors having very similar names. So I’d thought it be good for us to review the two suppressors and their differences.
The M4 is the oldest Allen Engineering design still made today. It is so old that it predated the OPS INC nomenclature, but the 3rd Model was created by the standardized of these early suppressors. The M4 is known for being the suppressor that was used on the Gordon Carbine. The M4 sleeves over a 14.5″ carbine barrel and indexes with a 3-piece collar on the FSB. People will often use “AE M4” or “AEM4” to describe the Allen Engineering M4, which leads to a lot of confusion. So if you are looking to build an accurate Gordon Carbine, the M4 is the suppressor you want to use.
The AEM4 (16th Model) is the latest Allen Engineering design still made today. It takes the more accessible B-Mount from the AEM3 (15th Model) and combines it with the baffle stack from the AEM5 (12th Model). It was never used on any notable military firearms, but sounds just like the AEM5 and is easier to mount. THE AEM4 IS NOT USED ON THE GORDON CARBINE.
Below I’ve included videos on each suppressor and basic specs for the M4 and AEM4 to highlight their differences.
| M4 | |
| Caliber | 5.56mm/ .223 Caliber |
| Diameter | 1.5″ |
| Length Past Muzzle | 5.25″ |
| Overall Length | 10″ |
| Weight | 24oz |
| AEM4 | |
| Caliber | 5.56mm/ .223 Caliber |
| Diameter | 1.5″ |
| Length Past Muzzle | 6.25″ |
| Overall Length | 8.5″ |
| Weight | 20oz |
| Mount | B (Short) |
