– CCU 16.2 in, PCU 12.2 in Stainless Steel
– Button Rifled – 1 Turn in 16″ Right Hand Twist – all Models and all Calibers
– OD is 0.695″
– Weight: CCU Basic unit with Fixed Stock and PCU approximately 5.7 lbs.
– Threading: 9mm 1/2x28 RH; 40SW/10mm 9/16x24 RH; 45ACP .578x28 RH
OVERALL LENGTH (as of 09/01/20):
|Fixed Stock: ||29 1/4 in |
|Length of pull: ||13 1/2 in |
|Telestock: ||Min. 24 5/8 in; Max. 31 1/8 in |
|Length(s) of pull: ||9, 11 1/2, 13 1/2, 15 1/2 in |
|M4 Style Stock: ||Min. 30 1/2 in; Max. 33 3/4 in |
|Length of pull: ||Min. 14 7/8 in; Max. 18 1/8 in |
|PCU: ||22 11/16 in |
|Fixed Stock: ||29 1/4 in |
|Length of pull: ||13 3/8 in |
|Telestock: ||Min. 24 3/4 in; Max. 33 1/8 in |
|Length(s) of pull: ||8 3/4, 11 1/2, 13 1/2, 15 1/2 in |
|M4 Style Stock: ||Min. 30 1/2 in; Max. 34 3/8 in |
|Length of pull: ||Min. 14 5/8 in; Max. 18 1/2 in |
|PCU: ||23 in |
Straight Blowback Action
MECH TECH IN COMPETITIVE SHOOTING
MECH TECH SYSTEMS CCU’S ARE CURRENTLY BEING USED IN USPSA AND PCC MATCHES. We understand that it meets power factors suitable for the 3-gun events and we have a number of customers using it in them. It makes sense of course to use a familiar grip and trigger pull for long gun shooting. It also simplifies the competition by using 2 ammos (pistol and shotgun) and one set of magazines for pistol/rifle. The USPSA has a pistol caliber carbine division and the CCU is being used there as well. The power gains available from the 16” barrel can be significant.
Selecting ammunition for your CCU
There are certain factors to consider when selecting ammunition for use in the CCU’s. The CCU is a ‘blow back’ type action. The main design element in a blow back is the weight (mass) of the bolt. This must be chosen to anticipate the ‘hottest’ loads encountered. The physics of a blow back action is such that the bolt mass and the bullet weight (mass) work together to limit the amount of the case which is allowed to move out of the chamber while the bullet is still in the bore. When the round is fired two things happen immediately:
1) the bullet begins to move out of the case mouth and up the bore
2) the case begins to move to the rear pressing against the breech face.
To elaborate, the case acts like a piston pushing out of the chamber to the rear and the only thing limiting the amount of movement of the case is the mass of the bolt – contrary to popular belief the recoil spring plays a negligible role in the initial case movement. The real design issue is to limit to a safe value the distance over which the case moves to the rear out of the chamber over the time that the bullet is still in the bore. As long as the bullet is in the bore the gas pressures are high and the case must have sufficient support to prevent case head blow-out or other pressure signs. The bolt weight in the CCU is enough for a good safety margin and as such the ammunition needs to be powerful enough for reliable ejection. Standard 9mm ammunition will work in the CCU. 9mm ammunition labeled as ‘target’ loads generally are not ‘hot’ enough to reliably cycle the action.
*USE ONLY AMMUNITION OF THE CALIBER FOR WHICH THE CCU IS DESIGNED. ONLY USE QUALITY AMMUNITION LOADED BY LICENSED COMMERCIAL MANUFACTURERS WHICH MEETS APPLICABLE SAAMI, CIP OR NATO STANDARDS. THE USE OF RELOADS OR AMMUNITION FROM NON-REPUTABLE SUPPLIERS HAS THE POTENTIAL TO BE UNSAFE AND WILL VOID THE WARRANTY OF THE CCU SHOULD DAMAGE OCCUR. MECH TECH CCU’S ARE NOT RATED FOR +P+ AMMUNITION AND STRONGLY ADVISES AGAINST THEIR USE.