Initial Test Results on Ultra 7CB

Discussion in 'Silencers' started by Robert Whitley, Oct 7, 2015.

  1. Robert Whitley New Member

    Robert Whitley
    Picked up my Ultra 7CB this past week and set up a rifle to accept it (a 260 IMP 30˚ with a 26" Bartlein 1:8" twist 5R barrel). Muzzle is threaded 3/4"x 28TPI to accept a TB CB brake with corresponding threading. One issue that concerned me was making sure the brake stays put on the muzzle without having to put it on with "crazy torque". The issue I see with the CB brake is when the suppressor is screwed onto it, no part of the brake protrudes beyond the back of the suppressor, so if the suppressor gets stuck on the brake and you have to twist it hard to try to get the suppressor off, the brake may come off with the can and there's no easy way to get the two separated at that point. With the TB suppressor/brake set up there's no locking mechanism (i.e. like the Silencerco ASR mount or the AAC 51T mount) to lock the suppressor in place on the brake threads, so when you screw the can on by hand you feel like you have to screw it on firm enough so it will not loosen when you shoot the rifle, things heat up, etc.

    SUGGESTION FOR THUNDERBEAST - If the back of the brake protruded a little beyond the back of the can and the protrusion had wrench flats on it that would go a long way to address the potential issue above.

    Indeed, the first time I put the brake on just to try things out in the shop, I put the brake on reasonably tight but with no Rocksett or Loctite and then screwed the can on with the stiff factory red grease they put on the threads of the can, and sure enough, when I went to back the can off the brake came with it. What a pain it was to get the the CB brake out of the can at that point (i.e. had to make a special tool to do it).

    SUGGESTION FOR THUNDERBEAST - Also get rid of that super stiff red grease (or whatever it is) that's on the threads of new cans and use something that's more consumer friendly for the initial screw-on (e.g. maybe something like Permatex 77124 Anti-Seize Lubricant - much thinner and the stuff is made to run up to 2400˚ f and is ideal for titanium, stainless steel, etc., high pressure and hi temp applications).

    In any case, I wound up using Loctite 2620 Threadlocker for the CB Brake installation on the barrel (i.e. a high temperature high strength Loctitie thread locker the is good up to 650˚ f.).

    Got zeros and range tested the Ultra 7 CB at my local 100 yard range today - POI with the can on (vs without the can) was 1.5 MOA low and a 1/4 MOA right (i.e. when I put the can on, I had to come up 1.5 MOA and left 1/4 MOA to hit the same POI). Taking the can off and putting it back on the POI did not move so the POI with the can on was repeatable.

    Accuracy was excellent with the can on and after getting set up I shot two .5 MOA 5 shot groups back to back taking the can off and putting it back on between the groups to make sure POI held true (it did).

    Can was pretty hot when I took it off after getting zeros and shooting it a bit (need a glove to do it) but everything worked well and was repeatable and the brake stayed on the muzzle when I took the can off, so I was and am a "happy camper".

    TBAC Ultra 7 is certainly light and quiet (although IMO you still need at least basic ear plugs with a cartridge like that and supersonic loads).

    Overall, it's a great product with the caveats noted. Thanks TBAC!

    Robert
     
  2. Zak Smith Operations

    • Instructor
    Zak Smith
    The brakes are made how they are to minimize overall length added to the rifle with the suppressor mounted.

    The instructions do say to use loctite, and that's why.

    If you do get it stuck, there is a very easy fix. Just clean the brake female threads and the rifle muzzle threads, and re-apply red loctite. Then screw on the suppressor quite hard. Wait 24 hours. The suppressor will unscrew from the brake.

    For normal use, you do not have to go crazy getting it extremely tight. Hand tight, and by that I mean pretty tight using one hand. Ratchet style locking mechanisms often have accuracy problems due to the "between teeth" problem. For a precision application, the CB mount locks up very tight due to the tapered shoulder surfaces.

    Glad to hear everything shooting good!
     
  3. Robert Whitley New Member

    Robert Whitley
    Honestly, if you said to me you had a new brake design that sets the suppressor forward an additional 1/4" but it has wrench flats on the back where it sticks out of the rear of the suppressor, I would go for that design every time to totally bypass and avoid the potential "easy fix" situation like you postulate. I realize I may look at things different than others do, but from my perspective an additional 1/4" OAL on the rifle is negligible compared to the practical aspects of the situation.

    Bear in mind, I'm not one for over tightening things, but the consequences of putting on a TBAC can not tight enough and perhaps having it loosen when your shooting and getting a baffle strike are harsh too.
     
  4. Zak Smith Operations

    • Instructor
    Zak Smith
    Once you get the brake loctited on your barrel with red loctite, it's not going to come off. Also, the CB mount actually gets tighter as a little heat it put into it; as far as I know they have never come loose while shooting any schedule that is appropriate for a Ti can
     
  5. Scott A New Member

    Scott A
    This very issue, while perhaps rare, is very very inconvenient when it happens, and I wager it's going to drive more and more people to the Area 419 adapters. It consumed HOURS of the last 10 days of my life trying to get the 338 Ultra unstuck. Hours and hours and hours.
     
  6. BobbyBobby New Member

    BobbyBobby
    Man, that sucks. Thanks for the heads up.
     

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