The machining quality of Ultradyne devices is outstanding. They all include a timing nut mounting system (no crush washers).
This is what we use on our 10.5” barrels, it is 1.69 inches in length.
ATHENA is Ultradyne's linear compensator. Muzzle rise has been optimized, with gas vented at an angle then forward. This sends a lower percent of sound and gasses back towards the shooter, optimizing sonic performance over recoil. Athena gives a cleaner appearance for a sleek look compared to...
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Keep in mind this is a linear compensator, the theory for us is that with that short of a barrel we want everything going away from the shooter as much a possible.