Cooper and suppressor threading problem - baffle strikes

fwafwow

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One of my newly threaded rifles causes strikes to the baffles of my suppressor, and I need some input.

I sent two Cooper model 52 rifles to Cooper to be threaded for a suppressor. Before I sent Rifle #1, I included specifications for the suppressor I planned to use (a Saker). After having Rifle #1 threaded, I told Cooper I wanted to send Rifle #2 "for the same treatment as the other one" but I mentioned I was planning now to use a different suppressor (Thunder Beast which I specified). I also mentioned that I would be using an Area 419 adapter (which I specified) for the appropriate shoulder for the TBAC can. Cooper did not ask for any additional information (including any different thread specs), but at the suggestion of the Cooper gunsmith, I did agree on a different pitch for Rifle #2 (9/16) vs. Rifle #1 (5/8) due to the barrel width. There was no other discussion about any variations in threading.

Rifle #1 seems to work fine with the TBAC and the adapter. Rifle #2, however, strikes the baffles. TBAC says the problem is that there was no recess cut into the barrel below the threads, as per the Can #1 specs (and as apparently was done on Rifle #1). TBAC said that the absence of a recess is the problem - which they have agreed to fix for a reasonable sum.

Did I do something wrong, and do I have unrealistic expectations here? I communicated in advance with the rifle company, adapter company and can company and thought having the rifle company do the threading made the most sense. We all seemed to be on the same page. After figuring out the problem, Cooper, however, just told me they decided to not cut a recess in Rifle #2 (as it would be "too thin" there and that would "cause accuracy issues"), but they never communicated this decision with me, or told me about the accuracy concerns. (If they had done so, I might have chosen not to thread that rifle.) Is this my fault? I guess I could have been proactive and sent the thread specifications for TBAC to be used on Rifle #2, but TBAC said that the specs are the same (both include a recess).

Cooper has been very responsive and pleasant, and has stepped up to pay for some shipping. But they are saying the baffle strikes (and resulting damage to Can #2) are not due to their work. I've asked several times for an explanation as to why they (apparently unilaterally) decided not to cut the recess and why they did not discuss that with me. I am still waiting on an answer.
 
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gbflyer

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That is difficult for me to follow. Recess? Are you talking about a relief cut for the threads near where the adapter for the suppressor shoulders up to the barrel? Got a picture? I’m no gunsmith nor am I familiar with every combination of connecting a suppressor to a barrel. I have threaded several of my own barrels that I use a Silencerco Harvester on. It is a direct thread to barrel, no quick connect sort of quarter turn adapter or the like.

It would seem to me that if the adapter or whatever type of connection you have from barrel to suppressor threads up against a shoulder on the barrel, with no gap at that connection, the only way to get a strike is if the threads are way out of alignment with the bore. My suppressor is probably .030 or more larger than the bore diameter. That should cover any minor deviations.

Do you have a picture?
 

gbflyer

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11boo

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I’ll be getting the suppressor alignment rod when I get my can. Too many stories like this. You would think a rifle company could do a proper thread job.
good luck.
 
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fwafwow

fwafwow

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5DB15FEE-7C00-4A4D-BFB1-F6D24B853DE6.jpeg

Sorry guys - yes, I’m trying not to throw the rifle company under the bus, which makes it a harder read. I will edit above shortly to add, but Can#2 is Thunder Beast and the adapter is Area 419.

I apologize if I’m using the wrong terminology. Please see the picture. The arrow pointing with 0.486 is what I’m referencing.
 
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Imo you should of provided the exact specs for the can you were wanting to use.

If after reading the specs, if they didn't think that would work on your barrel they should of delayed work until notifying you.

If you need something specific done you have to let them know.

There's way to many variables for them to keep track of them all.

In the end I'm going to tell you from my experience to just let it go. Get it fixed and move on.
 

Lawnboi

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My understanding…. Without the recess, the adapter could be shouldering off the edge of a thread, causing a mis alignment.

We need pictures.

Any particular reason you chose the area 419 adapters?
 
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What are you wanting out of the Rifle company?
I could see them cutting the recess for ya.

But I've never seen a company pay to have something fixed from another company.
 
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fwafwow

fwafwow

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Imo you should of provided the exact specs for the can you were wanting to use.

If after reading the specs, if they didn't think that would work on your barrel they should of delayed work until notifying you.

If you need something specific done you have to let them know.

There's way to many variables for them to keep track of them all.

In the end I'm going to tell you from my experience to just let it go. Get it fixed and move on.
I'm not sure that providing the exact specs would have mattered because they didn't follow the specs that they had, and they chose to not include the recess without informing me.

I realize I'm going to have to let it go, but I'm trying to figure out what I could have done differently, and perhaps give someone a heads-up if they are going down the same path.
 

gbflyer

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Something has to have a relief in order to shoulder up on the barrel. I cut a relief on the barrel as well. If the smith told you the barrel diameter wasn’t adequate for a relief, then he may need to think about that for a minute, as the threads he just cut are the same depth as a relief should be.

Silencerco has a relief on their adapter. Others may not. If your adapter is not shouldering up to the barrel, if there is a gap, do not fire it. You will probably get a strike. But, I guess you already learned that the hard way.
 
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fwafwow

fwafwow

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My understanding…. Without the recess, the adapter could be shouldering off the edge of a thread, causing a mis alignment.

We need pictures.

Any particular reason you chose the area 419 adapters?
That sounds like what I've been told.

I can add pictures - do you want the can, the threading, or what? I don't have the rifle, adapter or can in hand though at the moment. They are still with the rifle company.

Area 419 is a long story - I had chosen them for other cans and was trying to have consistency across rifles and cans.
 
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fwafwow

fwafwow

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What are you wanting out of the Rifle company?
I could see them cutting the recess for ya.

But I've never seen a company pay to have something fixed from another company.
Initially the thought was the threading might not have been concentric, and Cooper offered to re-thread or re-barrel (my choice). At this point I would just like to know if it is me, or Cooper - even if (as I suspect) I'm going to be paying for the fix and damage.
 
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fwafwow

fwafwow

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Something has to have a relief in order to shoulder up on the barrel. I cut a relief on the barrel as well. If the smith told you the barrel diameter wasn’t adequate for a relief, then he may need to think about that for a minute, as the threads he just cut are the same depth as a relief should be.

Silencerco has a relief on their adapter. Others may not. If your adapter is not shouldering up to the barrel, if there is a gap, do not fire it. You will probably get a strike. But, I guess you already learned that the hard way.
I'm told my can requires the same relief as the specs I sent for the first rifle. I never had any discussion with the smith about the relief. Yes, I did learn the hard way!
 

Lawnboi

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That sounds like what I've been told.

I can add pictures - do you want the can, the threading, or what? I don't have the rifle, adapter or can in hand though at the moment. They are still with the rifle company.

Area 419 is a long story - I had chosen them for other cans and was trying to have consistency across rifles and cans.

Pictures might not be needed if they threaded down to the shoulder. I’d guess that did it.

Griffin makes alignment rods. Did you look down your bore before shooting?

My guess is the above. In regards to thread spec. Different manufacturers obviously have their preferred thread, but Iv screwed my cans on plenty of factory threaded rifles to know that your thread was probably pretty janked up to cause a strike.

I personally don’t see the point of the area 419 system unless a guy wants to run a brake along side a supressor. Seems the more you stack the more you have to worry about. And honestly if your screwing onto a 419 adapter, TBAC thread spec dosnt mean jack

Atleast you learned this on a can that has a good company behind it. Good lesson. For others too, I’ll be paying more attention before I put my suppressors on any rifle.
 

gbflyer

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I'm told my can requires the same relief as the specs I sent for the first rifle. I never had any discussion with the smith about the relief. Yes, I did learn the hard way!

Sorry bud, that sucks. Good news is that you’ll always check it from now on.


Sent from my iPhone using Tapatalk
 
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Yeah I don't know why any Smith would ever cut threads without the relief. What that is ultimately going to cause is a miss alignment. When the threads of the can reach the end of the threads on your barrel it doesn't just stop. It stops because you are trying to force the threads to follow threads that aren't there. I'm guessing he either used a CNC or a Die.
It's really hard to explain in words. But man I can't belive they would do that. There should always be a relief!!
I don't think that you did anything wrong.
 
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After looking at a few of my rifles it does appear a relief is standard.
And I can see why. Indexing off the shoulder.

But interesting enough I have 2 rimfires that were threaded my the same Smith.
Same for my 2 rifles. Not the same as in me and you.
And they were supposed to be the same spec.
One has a relief and one does not.
Luckily for me they both work fine.
 
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Yeah, I would be more inclined to believe that the problem is the adapter, not the threads on the barrel or the can.
If there are enough threads on the barrel and enough of a shoulder, not having a relief shouldn't cause any misalignment (unless those threads are really loose).
The other thing to check is that the threads are concentric to the bore.

With the number of readily available cans that you can change the mounting options on, I wouldn't be using an adapter at all.
 

Xbow hunter

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Bore alignment rods are cheap compared to the damage that can be done and the time without a suppressor they cause. If you don’t want to buy an alignment rod find a good gunsmith and they can check it and possibly fix any problems before shooting it and finding them.
 
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