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Got my stamp and suppressor couple weeks ago. Was trying it out this weekend and man is it awesome! Only problem I noticed was brass was really dirty. Other than that, everything seemed to cycle properly, brass landing at 2 oclock. I know shooting supressed causes access back pressure, but is this normal? How do you tell if it is too much? Anything else I should check? New to shooting suppressed so any info is appreciated.
Running it on an 18" AA barrel, rifle length gas, non adjustable block, using factory Hornady 123 custom
Thanks
Nick
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3 o'clock is supposed to be ideal. You are slightly overgassed. Dirty brass is normal for your situation. It can happen when undergassed as well.
DO NOT LEAVE A ROUND IN CHAMBER OVERNIGHT IF FIRING SUPPRESSED. IT CAN CORRODE IN PLACE.
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Been there, done that Double Naught?
Sticks
Catchy sig line here.
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03-26-2017, 02:17 AM
(This post was last modified: 03-27-2017, 02:04 AM by Klem.)
Yes, unfortunately that is the downside of using a suppressor; your receiver and brass get dirty.
Spent cases before cleaning; suppressor on the left and no suppressor on the right.
![[Image: cases_zpsu3f5gq4z.jpg]](http://i1374.photobucket.com/albums/ag436/stupidbernard/cases_zpsu3f5gq4z.jpg)
Like the other guys are saying...Burnt powder cakes on the inside surfaces, especially the corners. It then attracts moisture as it cools. This then turns corrosive. Not just in the suppressor but near it. Like if you put a damp sponge in the receiver. Some metals are more prone to corrosion than others and especially when two different metals are in contact. In this instance you get an electrochemical or galvanic reaction (e.g. brass in chamber).
Suppressors that come apart make for easier cleaning. One or two shots is not a big deal but 50 is a definitely worth cleaning. Just plenty of degreaser or WD40, elbow grease and paper towels. And take your suppressor off after you finish shooting at the first opportunity.
Also, watch that it doesn't come loose as it heats up and expands. Something that feels rock solid tight when cold will soon not be if you are firing faster than one round a minute. Last thing you need is it creeping forward on the threads and then getting a baffle strike as run-out kicks in. Keep checking it if it is not locked in by a ratchet system.
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Running a heavier buffer has helped a lot with the dirty cases in my rifle.
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03-28-2017, 12:26 AM
(This post was last modified: 03-28-2017, 04:13 AM by Klem.)
tpk Wrote:Running a heavier buffer has helped a lot with the dirty cases in my rifle.
Good advice from tpk... I also use an adjustable gas block. If I don't adjust the gas down it spits out the cases at 2 O'clock and throws them further from the gun.
I have used suppressors in various guns and calibres. In semi-auto's all the brass comes out dirty.
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Good to know. Running an AA overwatch barrel. Having trouble trying to find what diameter block I need. In the mean time I've ordered some heavier rings for silent capture.
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03-29-2017, 02:48 AM
(This post was last modified: 03-29-2017, 02:52 AM by win.308stealth.)
Nick-- you mentioned you got your stamp back a few weeks ago. If you don't mind, can you let me know when you submitted your paperwork and if you know, when was your check cashed. Submitted my paperwork beginning of June 2016, check was cashed June 28. The wait is killing me.
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I submitted move in June also. Check was cashed in January.
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win.308stealth Wrote:Nick-- you mentioned you got your stamp back a few weeks ago. If you don't mind, can you let me know when you submitted your paperwork and if you know, when was your check cashed. Submitted my paperwork beginning of June 2016, check was cashed June 28. The wait is killing me.
http://www.nfatracker.com/nfa-transfer-time-tracking/
According to the trend graph, you should be getting close. Add 2 weeks or so for mailing the stamp, so I would say by the end of April it should be in your hands.
