Combat Application Technologies (CAT) DD/A1, 7.62, **NFA Item**

1. CARTRIDGE DESIGNATION

C.A.T’s Dirty Dave (DD) 7.62x51mm (.308Win) suppressors are designed specifically for the .308Win cartridge pushing a projectile in the range of 2600-2900fps. The DD is not designed for cartridges/loads pushing past 3200fps or with a projectile diameter greater than 7.82mm (.308in).
While very few users will have access to the equipment required to measure chamber pressure, it is a simple task to look up the maximum chamber pressure for the cartridge you are firing on the web. Any SAAMI approved cartridge will include this as part of the documentation. If the cartridge you are intending to use with the Dirty Dave falls below the velocity, pressure and diameter of a .308Win (as described above), you are cleared to move to Step 2: Barrel Length.

2. BARREL LENGTH

C.A.T recommends that the user find their own barrel length restriction via the following method. If both your muzzle velocity and max chamber pressure fall under that of the .308Win (listed above), then you should also ensure that the projectile (bullet) is stable after leaving your barrel. Many shortened barrels – especially if they were cut aftermarket – have a twist rate that is commiserate with that of a much longer barrel. If the specific round you are firing has too little or too much twist (or too little velocity in the case of very short barrels), the projectile has a significant propensity to become unstable in flight. Think of a tightly spiraling football (stable) versus a football lobbed end-over-end (unstable). If your projectile is yawing or tumbling, it is almost always evident on paper. We recommend you shoot 5-10 rounds at a paper target somewhere between 25-50yds and inspect the holes created by the projectiles. While not a perfectly scientific test, if the diameter of the hole closely matches that of the bullet, then your projectile is most likely stable. If the hole is not circular, noticeably bigger than the projectile or you observe the profile of the bullet on the paper (keyholing), then no suppressor -including a C.A.T suppressor - should be used with that particular system (firearm and ammo).