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Discussion Starter #1
I took my SBR out today to reconfirm my zero. At 15 yards the gun was hitting dead center with 115 and 147 grain ammo. I then mounted my Trident 9 and noticed it was off by several feet so I tried all the indexing spots. It then went 2 feet low but a nice group. Third index was a buckshot pattern. I even had a light baffle strike which left pieces of copper shavings in the LCD. I took the can off and it was back to shooting center mass again. I heard of a few bad Tri-lug LCDS that made it out to the market. Any help would be appreciated. I did send a email to SWR also. The Barrel is a RCM installed by Chopstix Kidd. I am inclined to say it is the LCD, but who knows, it could be a out of spec Tri-lugged barrel.

By the way. The can is fine on my Sig and Glocks with regular LCD.
 

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By my way of thinking if the barrel was the problem then your POI would not change when indexing the can differently. I would be inclined to think the problem is with the 3 lug adapter.
 

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Does your POI change if you take the can off and rotate it (with the 3 lug mount, rotating in 3rds)? Your getting strikes so you really shooting really isn't a good idea until you get it figured out...
 

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I'm no suppressor expert, but an LCD refers to a threaded piston (usually spring-loaded) for tilting barrel actions (Browning type) and a 3 Lug mount is a specialized fixed barrel mount. I guess I'm confused with how you've used 3 LUG and LCD interchangeably. How is yours attached? Is it a Navy barrel and you are using the LCD piston to thread it onto the barrel, or are you using a 3-Lug mount for a quick-detach on the lugs themselves?
 

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Discussion Starter #6
It is a 3 lug mount. I am not running a boosted can on a fixed barrel. LCD was the wrong word in this particular post. I guess I figured those familiar with the Trident would get what I was talking about when I said indexing points....lol.
 

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Don't know if it's at all related, but 115-gr and 147-gr should be run with two different locking-pieces. 100-degree is fine for the 115-gr but you should run the 80-degree with 147-gr or heavier. And make sure you are running sub-sonic ammo with the can. While everything I just suggested apply more-so to cycling problems, I would at least make sure you are setting up the firearm as suggested and go from there.

Also, did you remove the thread protector? Some cans will not lock-up properly with the TP removed.
 

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Discussion Starter #8
Don't know if it's at all related, but 115-gr and 147-gr should be run with two different locking-pieces. 100-degree is fine for the 115-gr but you should run the 80-degree with 147-gr or heavier. And make sure you are running sub-sonic ammo with the can. While everything I just suggested apply more-so to cycling problems, I would at least make sure you are setting up the firearm as suggested and go from there.

Also, did you remove the thread protector? Some cans will not lock-up properly with the TP removed.
Hello Joe,

The gun has no cycling issues at all. It runs 100%. I did remove the thread protector as the 3 lug mount will not fit with it attached. I took the 3 lug apart today and completely cleaned and greased it. It now attaches much more smoothly than before. I will give it another try. A dirty mount could be to blame. Do you have a source for thinner thread protectors?
 

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Hello Joe,

The gun has no cycling issues at all. It runs 100%. I did remove the thread protector as the 3 lug mount will not fit with it attached. I took the 3 lug apart today and completely cleaned and greased it. It now attaches much more smoothly than before. I will give it another try. A dirty mount could be to blame. Do you have a source for thinner thread protectors?
If you removed the TP, I bet that was a big contributor. The TP has to be trimmed shorter. Just send me your TP with return shipping and I'll trim it down and re-park it for you.
 

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So it is not recommended to attach a 3-lug suppressor with the TP off?

I am just asking because I get my K clone back tomorrow after have a RIM threaded barrel put on it but I like to use the 3-lug

I basically got the threaded barrel for looks.
 

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Discussion Starter #12
If you removed the TP, I bet that was a big contributor. The TP has to be trimmed shorter. Just send me your TP with return shipping and I'll trim it down and re-park it for you.
Joe,

Awesome customer service as always. I'll get it out to you ASAP. IM sent also.
 

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So it is not recommended to attach a 3-lug suppressor with the TP off?

I am just asking because I get my K clone back tomorrow after have a RIM threaded barrel put on it but I like to use the 3-lug

I basically got the threaded barrel for looks.
By design of the 3-lugs, no. But if your suppressor uses a spring-lock then the wieght of the suppressor could cause it to tilt with the TP removed. If the base of the suppressor is shallow to come to rest against the actual muzzle, then the flush fit of most TP's can create a clearance issue. This is why the factory German N-barrel TP's leave approx 1/2-3/4 of a turn of threads exposed.
 

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My buddy had the same issue with the TP from RCM. The knurling is the culprit and it's only a couple thou over spec and can be fixed easily. Take a dremel sanding drum wheel and put the TP on it and secure it just like you normally would the sanding drum. Put it on a medium speed and touch it with some 120 grit or higher sand paper until you can see that you are knocking the high spots from the knurling. Try sliding it into the trilug, if ti fits you're good if not, repeat. Go slowly and it should only take about 10 min. Remember that it's likely only .002-003" over size and be judicious about sanding and you should be good.

For the record, you should NEVER fire a 3 lug can without the TP in place. As was said earlier the weight of the can is bearing on it and alignment of the can depends on a good slip fit. Shooting without a TP in place is asking for a baffle strike.
 
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