User Panel
[#1]
You need to continue the threading on the barrel (downturn) so that the threading is longer. Send it to ADCO. If you are going to do that, it is best if they can taper profile the shoulder so it fits even better.
Also, you should remove the break portion of the attachment when attaching to a rifle. If you have used that mount before, you may need a new proprietary SIG crush washer to get it timed (aligned). |
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[#2]
Quoted:
You need to continue the threading on the barrel (downturn) so that the threading is longer. Send it to ADCO. If you are going to do that, it is best if they can taper profile the shoulder so it fits even better. Also, you should remove the break portion of the attachment when attaching to a rifle. If you have used that mount before, you may need a new proprietary SIG crush washer to get it timed (aligned). View Quote What is the break portion? It's a new crush washer. So I have to send it in to get more of the barrel threaded, is that normal? I thought I've seen people with the Sig suppressor QD mount on their RARR and no one said anything about having to downturn the barrel. How much will it cost? Any idea on turn around times? |
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[#3]
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[#5]
Just counting the threads, the Ruger doesn't appear to be too long. What happens when you unscrew the brake portion and mount the rear half of the muzzle device (as suggested above)? That's how I've seen those being mounted. Rear half first and then the brake portion is timed with the crush washer.
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[#6]
Quoted:
Just counting the threads, the Ruger doesn't appear to be too long. What happens when you unscrew the brake portion and mount the rear half of the muzzle device (as suggested above)? That's how I've seen those being mounted. Rear half first and then the brake portion is timed with the crush washer. View Quote Tried this. Didn't change it. He said it is less then 2 full turns til tight and he'd like to see 4-6 full turns. He said he'd like to see 1/2" of threads used and it's about 1/8" right now. Could I have the wrong mount? |
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[#7]
Doesn't SIG make a mount for the standard 5/8-24 x .600" threads?
If they only make them for their own tapered barrels, I'm glad I found out now. |
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[#8]
Quoted:
Tried this. Didn't change it. He said it is less then 2 full turns til tight and he'd like to see 4-6 full turns. He said he'd like to see 1/2" of threads used and it's about 1/8" right now. Could I have the wrong mount? View Quote I suppose it's possible. Idk if a 1/2x28 will screw on a 5/8 that far... |
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[#9]
It's made to fit the barrel of sig rifles with their proprietary taper. It indexes on the taper so you can't simply make you muzzle threads longer.
There are a couple companies who make adapters to fit the sig qd adapters on standard 1/2-28 and 5/8-24 threaded barrels. |
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[#10]
Quoted:
It's made to fit the barrel of sig rifles with their proprietary taper. It indexes on the taper so you can't simply make you muzzle threads longer. There are a couple companies who make adapters to fit the sig qd adapters on standard 1/2-28 and 5/8-24 threaded barrels. View Quote Thanks. Could you name a few? Because I looked and couldn't find any. |
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[#11]
Quoted:
It's made to fit the barrel of sig rifles with their proprietary taper. It indexes on the taper so you can't simply make you muzzle threads longer. There are a couple companies who make adapters to fit the sig qd adapters on standard 1/2-28 and 5/8-24 threaded barrels. View Quote I just screwed mine on and it seems to work. Who makes the above adapters to fit the SIG QD adapters? Mark |
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[#12]
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[#13]
Quoted:
Doesn't SIG make a mount for the standard 5/8-24x.600" threads? If they only make them for their own tapered barrels, I'm glad I found out now. View Quote I agree. This doesn't help the OP but I'll be very put off of Sig cans if they don't offer muzzle devices for "normal" factory threaded barrels. I have the Ranch in 300 BLK and 5.56 and haven't had a single issue with multiple different suppressors being installed on them. I wouldn't consider spending the extra time and money to get a non-standard profile added to them. |
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[#14]
I saw the adapters in a couple YouTube reviews when I was considering one. I ended up not going with the sig because it took too long for them to show up on shelves so I never had to follow up on the adapters.
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[#15]
The Sig bases have an un-threaded portion for their taper, and then threads. Call Sig, per thier CS and Silencer guys, if you properly torque the base on with the applied Rocksett (it's in the manual) then you will not have a problem. The QD's do work fine on non-Sig tapered barrels.
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[#17]
I have a standard CMMG 300BO barrel with 5/8 threads and the SIG adapter snugs up nice and tight with plenty of thread engagement. It is not tapered. Like said above, maybe Ruger just has short threads. If you taper the non tapered portion on your barrel, it should allow the adapter to go on tighter.
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[#18]
Quoted:
I have a standard CMMG 300BO barrel with 5/8 threads and the SIG adapter snugs up nice and tight with plenty of thread engagement. It is not tapered. Like said above, maybe Ruger just has short threads. If you taper the non tapered portion on your barrel, it should allow the adapter to go on tighter. View Quote Maybe, but the threads seem to be plenty, it's just that the mount's threads don't start until well into the mount. |
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[#19]
Quoted:
https://youtu.be/-KRq2SHeoj0 Now I think the adapters were the other way around, to give a square shoulder on a sig tapered barrel? It's been so long that I can't remember and I'm doubting myself! The Rugers do have shorter than average threads as I recall, perhaps that is the issue? How long are the threads on your ruger? Edit: found it, I was thinking of adaptor to put square shoulder on sig barrel. http://imagizer.imageshack.us/v2/800x600q90/633/mHyUxh.jpg View Quote The RARR seems to have at least this many threads as the barrel pictured. |
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[#20]
Can anyone out there post a cross section diagram/dimensions of the SIG mount?
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[#21]
Quoted:
Can anyone out there post a cross section diagram/dimensions of the SIG mount? View Quote My friend said the adapter is hitting the shoulder, so basically not enough threads for that particular adapter. I hate how the threads in the adapter start so deep, not right on the outside of the adapter. I haven't seen any other adapter that would work, hopefully there is one out there. I'd rather get a different adapter or modify the adapter than permanently alter the rifle barrel. |
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[#22]
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[#23]
Quoted:
http://truthaboutguns-zippykid.netdna-ssl.com/wp-content/uploads/2015/04/IMG_9151.jpg http://truthaboutguns-zippykid.netdna-ssl.com/wp-content/uploads/2015/04/IMG_9153.jpg View Quote If I didn't state it properly, what I am hoping for are the dimensions of the muzzle device itself, in particular the internal threads and space from the rear of the device to the start of the threads. |
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[#24]
Quoted:
Thanks again for your constant attention to questions on this board. If I didn't state it properly, what I am hoping for are the dimensions of the muzzle device itself, in particular the internal threads and space from the rear of the device to the start of the threads. View Quote |
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[#25]
Just got mine home.
I was floored. This is BS and there is nothing in the description when buying the suppressor that says you'll need special barrel contour and threading. |
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[#26]
Hollister says that it works with barrels with traditional shoulders:
Failed To Load Title Did you guys somehow get a bad batch of 5.8x24 threads? |
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[#28]
Quoted:
Hollister says that it works with barrels with traditional shoulders: https://www.youtube.com/watch?v=-KRq2SHeoj0 Did you guys somehow get a bad batch of 5.8x24 threads? View Quote I don't. Maybe if it was silver soldered....but not just tension or even rocksett |
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[#29]
Quoted:
You trust a mount that only engages 2-3 threads? I don't. Maybe if it was silver soldered....but not just tension or even rocksett View Quote View All Quotes View All Quotes Quoted:
Quoted:
Hollister says that it works with barrels with traditional shoulders: https://www.youtube.com/watch?v=-KRq2SHeoj0 Did you guys somehow get a bad batch of 5.8x24 threads? I don't. Maybe if it was silver soldered....but not just tension or even rocksett |
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[#30]
Quoted:
You trust a mount that only engages 2-3 threads? I don't. Maybe if it was silver soldered....but not just tension or even rocksett View Quote I'm not a Mechanical Engineer but the only rule of thumb I've heard of is the amount of thread engagement should be at least equal to the diameter of the bolt/hole. That's nothing I have any empirical evidence for though. |
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[#31]
The adapter is tapered inside too. Thus if the barrel is either tapered or simply has standard length threaded portion, then it will fit. The barrel does NOT need to be tapered but in the OP's case, it looks like the factory has a shorter run of threads. Regular AR throws down with a flat / squared shoulder is fine.
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[#32]
Those of you with issues, are you taking off the muzzle brake or flash hider end BEFORE installing the mount? You have to take that part off, install the main body of the mount, then install the muzzle brake or flash hider front piece using the included crush washer.
The Sig mounts will work with a Sig barrel taper or a standard square shoulder. I haven't seen any issues with Sig mounts until this thread, and the other one posted yesterday, so I would lean towards improper installation before saying the mounts or barrel threads are bad. |
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[#33]
Quoted:
Those of you with issues, are you taking off the muzzle brake or flash hider end BEFORE installing the mount? You have to take that part off, install the main body of the mount, then install the muzzle brake or flash hider front piece using the included crush washer. The Sig mounts will work with a Sig barrel taper or a standard square shoulder. I haven't seen any issues with Sig mounts until this thread, and the other one posted yesterday, so I would lean towards improper installation before saying the mounts or barrel threads are bad. View Quote |
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[#34]
Quoted:
The adapter is tapered inside too. Thus if the barrel is either tapered or simply has standard length threaded portion, then it will fit. The barrel does NOT need to be tapered but in the OP's case, it looks like the factory has a shorter run of threads. Regular AR throws down with a flat / squared shoulder is fine. View Quote |
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[#35]
I believe the issue may be a bad batch of adapters.
The threads did not run deep enough to engage traditional threaded barrels. SS is sending out a new one. I'll update. EDIT: after watching that video Engineer posted in almost convinced it's a bad mount. The ones in the video appeared to engage the threads right away and and screw down for several rotations. |
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[#36]
First time around, I made the mistake of using a crush washer with the QD mount. Rocksett did not have enough to grab and the QD mount came off with the silencer. As the video shows, just install and tighten flat against your barrel. No issues so far after a couple range trips with my AR.
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[#37]
Quoted:
I believe the issue may be a bad batch of adapters. The threads did not run deep enough to engage traditional threaded barrels. SS is sending out a new one. I'll update. EDIT: after watching that video Engineer posted in almost convinced it's a bad mount. The ones in the video appeared to engage the threads right away and and screw down for several rotations. View Quote |
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[#38]
Didn't say "bad batch" but they did send me a label to send it back for a replacement. Looking that the one they have listed on the site and the one in the video leads me to believe there probably was a few that made it out the door that were bad.
I'll update. |
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[#39]
Quoted:
I believe the issue may be a bad batch of adapters. The ones in the video appeared to engage the threads right away and and screw down for several rotations. View Quote It doesn't seem possible for it to engage the threads right away, given the unthreaded taper area. Hope to get my hands on a mount this weekend and take some measurements. Otherwise, will definitely be checking it out at the SIG booth during the NRA Convention in Atlanta next month. |
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[#40]
Just broke out the calipers.
Threads begin at .40 inch from the shoulder. The first actual thread measures at .415 depth from the shoulder. Of the several different thread spec drawings I've seen for 5/8" thread pattern every single one is .62 inches from the muzzle to the shoulder. That leaves .2 inches of engaged threads. LESS than a 1/4inch. So, yeah....something is either wrong with these mounts or Sig messed up by not telling people that the barrels need some funky thread pattern. |
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[#41]
Quoted:
Just broke out the calipers. Threads begin at .40 inch from the shoulder. The first actual thread measures at .415 depth from the shoulder. Of the several different thread spec drawings I've seen for 5/8" thread pattern every single one is .62 inches from the muzzle to the shoulder. That leaves .2 inches of engaged threads. LESS than a 1/4inch. So, yeah....something is either wrong with these mounts or Sig messed up by not telling people that the barrels need some funky thread pattern. View Quote |
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[#42]
How far the sig QD threads on also depends on the OD of a square shoulder. If it is small it could fit partway inside the tapered portion of the sig qd, if it's too big then maybe not at all.
It's a good design and no big deal to make your own propietary threads, but I thought it was ridiculous when they released it without an adaptor for square shouldered barrels. |
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[#43]
Quoted:
Just broke out the calipers. Threads begin at .40 inch from the shoulder. The first actual thread measures at .415 depth from the shoulder. Of the several different thread spec drawings I've seen for 5/8" thread pattern every single one is .62 inches from the muzzle to the shoulder. That leaves .2 inches of engaged threads. LESS than a 1/4inch. So, yeah....something is either wrong with these mounts or Sig messed up by not telling people that the barrels need some funky thread pattern. View Quote |
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[#44]
Quoted:
I believe the issue may be a bad batch of adapters. The threads did not run deep enough to engage traditional threaded barrels. SS is sending out a new one. I'll update. EDIT: after watching that video Engineer posted in almost convinced it's a bad mount. The ones in the video appeared to engage the threads right away and and screw down for several rotations. View Quote Is that the one you measured or did you measure the original bad adapter? |
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[#45]
Update: Resolved
Apparently there are different adapters for different rifles. The suppressor comes with the adapter that fits the Sig line of weapons, no surprise there. I wish they would have put this on their website, that different rifles require different adapters. The new adapter I received definitely has a lot more threads in it and they start far earlier making the threads start far closer to the end of the adapter. I'm happy that I didn't have to do anything drastic like downturn the barrel or buy a custom adapter. I know that Sig has been knocked in the past for having some horrible customer service but I've got to say that I was treated great. Their employee went out of his way to take care of me. |
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[#46]
Got a replacement adapter from SS. It definitely engages more threads but....and this is a big 'but'....it still only engages about half the threads on the muzzle.
So I suppose I have three options.... 1) Use 'as is' and put on rocksett on it and hope half the threads is enough. 2) Have the barrel turned to the SIG tapered shoulder 3) Have the square shoulder moved back a little further allowing more threads to engage. #3 is probably the easiest for a local machinist to accomplish. I don't feel like paying the expense of shipping this boat anchor of a barrel to have the work done. Shipping will most likely be around $35-40 there plus return shipping...plus machine work. Setting the shoulder back shouldn't be too hard. I just don't feel comfortable with only .35" of threads engaged even if there is rocksett involved. SIG (and Silencer Shop) really need to put in big bold letters that this adapter requires special barrel threading/contouring. |
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[#47]
Quoted:
Got a replacement adapter from SS. It definitely engages more threads but....and this is a big 'but'....it still only engages about half the threads on the muzzle. So I suppose I have three options.... 1) Use 'as is' and put on rocksett on it and hope half the threads is enough. 2) Have the barrel turned to the SIG tapered shoulder 3) Have the square shoulder moved back a little further allowing more threads to engage. #3 is probably the easiest for a local machinist to accomplish. I don't feel like paying the expense of shipping this boat anchor of a barrel to have the work done. Shipping will most likely be around $35-40 there plus return shipping...plus machine work. Setting the shoulder back shouldn't be too hard. I just don't feel comfortable with only .35" of threads engaged even if there is rocksett involved. SIG (and Silencer Shop) really need to put in big bold letters that this adapter requires special barrel threading/contouring. View Quote |
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