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View Full Version : A question about "cans"


ZeSpectre
February 23, 2009, 09:22 AM
Another thread raised this question in my head and rather than hijack i'll just start a new thread.

For those of you who have "cans" (supressors, mufflers, whatever) on your guns...

How long to they last? Are they a "consumable" item that will get replaced?
Do they require special cleaning and/or maintenance? How much work is it?
Do they have much impact on accuracy and/or velocity/power?

I just have an itching curiosity wanting to be scratched. Thanks!

jmorris
February 23, 2009, 09:55 AM
The #1 cause of destruction is a loose suppressor causing a bullet to impact the baffles. A sealed .22 rimfire can will also fill with fouling and loose its effectiveness. Older designs used “wipes” that had to be changed out on a regular basis. The same wipes also negatively effected accuracy as well.

Most of the time the addition of a suppressor will tighten up groups although adding a suppressor does affect zero and not the same for different firearms. I would guess it has to do with harmonics, weight and rigidity of different barrels.

I’m not a clean freak so with my suppressors that I can take a part, I just wipe the fouling off and put the parts together (antiseize on the threads). Some sandblast to clean but a small amount of material gets removed with this process.

ZeSpectre
February 23, 2009, 10:18 AM
very interesting. Thanks.

aroundlsu
February 23, 2009, 12:20 PM
This is a question I get asked almost every time I'm at the range.. A modern centerfire can won't need cleaning at all and will probably outlive the host gun if it doesn't get physically destroyed from a baffle strike.

As was stated already, a .22 can will get so dirty it may become ineffective after about 10,000 rounds. They can be dipped in a solution of vinegar and hydrogen peroxide to dissolve the lead or some can be taken apart for cleaning.

At less than 100yds I see no change in impact with my M4-2000 .223 can on a 9.25" SBR. YMMV on that point, however since adding a one pound weight to the end of your gun should very well change the point of impact.

My biggest real life issue is my .223 silencer gets INCREDIBLY HOT! After a few mag dumps you can see heat mirages through the optic and past that you can't touch anything with the silencer for at least an hour or it is a serious fire and burn hazard. I'd guess it is approaching 1,000 degrees F. I put a Kevlar shroud over the can when I'm done to at least shield anything from touching it accidentally.

Bartholomew Roberts
February 23, 2009, 10:31 PM
How long to they last? Are they a "consumable" item that will get replaced?

They don't last forever. The "blast baffle" takes the brunt of the muzzle blast and will eventually wear out like any other mechanical device. My OPS Inc. 16th Model is warrantied to 30,000 rounds I believe, which means it will probably outlast the barrel it is on and then some.

Do they require special cleaning and/or maintenance? How much work is it?

On the 16th Model (.223 suppressor), there is no cleaning or maintenance. Just shoot it.

Do they have much impact on accuracy and/or velocity/power?

I've fired the OPS can over a chrony and then bare muzzle for comparison, no real difference in velocity. Shooting from the bench or a stable position, there appears to be a tiny accuracy advantage with the can on (slightly tighter groups). On the flipside, when you are shooting and moving or firing fast from a fighting stance, having 20oz of weight out on the end of the barrel really screws with your balance. It takes a fair amount of practice to get used to it on a 16" barrel; but shortening the barrel helps make it more controllable.

One of the things I don't think most people appreciate about suppressors is that they aren't all that quiet. The .223 suppressors are still about as loud as an unsuppressed .22LR. The pistol caliber suppressors can be more quiet; but even when using subsonic ammo, a 147gr slug hitting something is going to make a bit of noise - not to mention action noise.

Second, suppressors of all kinds create backpressure and vent a fair amount of gas and carbon into your face through the ejection port. This is a bit worse with AR15s because the charging handle design lets it vent right back into your face as well sometimes; but it is true of all suppressed semi-autos, whether piston or direct impingement. This same backpressure means more cleaning and lube necessary to keep things running as well since you get increased fouling with the backpressure and the extra gas tends to dry off the lube quicker.

Third, as already mentioned, suppressors basically work by converting sound into heat. They get really hot and they get really hot really fast. Flight gloves are almost a must if you are going to do more than a magazine's worth of shooting with a .223 suppressor.

freakshow10mm
February 24, 2009, 12:46 AM
A suppressor heats up 7ºF for every round fired.

Here's a very cool infrared video.

http://www.youtube.com/watch?v=BAPx-5GeE6c

ZeSpectre
February 24, 2009, 08:15 AM
One of the things I don't think most people appreciate about suppressors is that they aren't all that quiet.
I've fired a suppressed .22 and been near a suppressed AR that was being fired so I know what it's really like but yes you are right, nothing like the "phtttt phttt" of the movies.

Second, suppressors of all kinds create backpressure and vent a fair amount of gas and carbon into your face through the ejection port. This is a bit worse with AR15s because the charging handle design lets it vent right back into your face as well sometimes


Ahhhh, that clears something up for me. I had the opportunity to shoot the suppressed AR and when the guy realized I was a "lefty" he said "nah, you don't what to shoot that, here's something else". I thought it odd but there was a lot going on so I never questioned him (it was his gun after all) so now I understand why.

Freakshow: THAT was a COOL (or maybe I should say HOT) video!

RAnb
February 24, 2009, 08:46 AM
Something that you may appreciate; a 20 decibel decrease in noise is 100 times reduction, 30 decibels, 1000 times. This is amazing for a small tube muffler in my opinion.

Ranb

freakshow10mm
February 24, 2009, 11:33 AM
Suppressors aren't that quiet?

I have a design (under license) for a .300 Whisper suppressor that registers 110db when fired with a bolt action rifle using subsonic ammunition (220gr SMK @ 1040fps). A suppressed .22 with subsonic is about 112dB. Snapping your fingers smartly will get 115dB. That's a 48dB reduction. Plenty below hearing safe threshold.

There is little benefit to trying to suppress supersonic ammunition.

RAnb
February 24, 2009, 12:57 PM
I think there can be a great benefit to suppressing rifles shooting supersonic ammo. While the bullet flight noise is louder, the muzzle blast is still suppressed by a great deal. Shooting under weather protection can result in noise levels that are not hearing safe though; this is what I experienced shooting my suppressed ar-15.

Ranb

Bartholomew Roberts
February 24, 2009, 02:10 PM
Suppressors aren't that quiet?

No, by and large they aren't. Especially if you are comparing them to the mythical "Hollywood" suppressor that lets you shoot in the next room without alerting people in the hallway.

Basically a firearm's sound has three elements: supersonic bullet flight noise (a mini-supersonic boom that accompanies the bullet), expanding supersonic gases at the muzzle (muzzle noise) and action noise (the noise of the action cycling). Most suppressors only act to reduce the muzzle noise (although the MP5SD suppressor I am familiar with also reduces muzzle velocity).

I am sure the suppressor you mention is quiet since by using subsonic rounds it eliminates supersonic flight noise. By using a bolt action, it eliminates both action noise and any venting of gases through the open action. That leaves only the gases exiting the muzzle, which is where the suppressor does its work. However, all of these require compromises in order to achieve that level of quietness (no semi-autos, subsonic ballistics).

Most suppressed firearms don't address all three categories though.

And all of that ignores another category - impact noise. Your .300 Whisper may be as loud as a finger snap; but I bet that 220gr SMK moving out at 1040fps makes a big racket when it hits something - particularly inside a structure. Even outside, I bet it makes a noticeable thud. I know one of the fun things I noticed with my .223 suppressor is that muzzle noise was reduced enough that I could separately hear the impact of the bullet against the target backer and dirt berm from 100yds away.

There is little benefit to trying to suppress supersonic ammunition.

Depends on what you are trying to achieve I guess. If you want Hollywood quiet and that is your priority, then I would agree. Obviously there is some use for them though or your firm wouldn't sell so many suppressors designed around supersonic calibers ;)

telowbird
February 24, 2009, 05:14 PM
Is it the suppressor or the ported barrel that reduces muzzle velocity on the MP5SD?

freakshow10mm
February 24, 2009, 11:46 PM
Obviously there is some use for them though or your firm wouldn't sell so many suppressors designed around supersonic calibers
Civilians don't have much practical use for suppressing a supersonic cartridge. The practical benefits are recoil reduction, muzzle blast reduction, some SPL reduction. Suppressors are more beneficial overall in the role of recoil reduction than a muzzle brake. A muzzle brake is the opposite of a suppressor.

The reason for my company making and offering suppressors for supersonic cartridges is aimed at LE who can benefit from these in close quarters indoors. Most civilians don't equip their HD weapon with a suppressor for fear of the public image of suppressors being used against them. If a civilian customer wants to buy a .223 suppressor for his AR15 to cut 25-30dB on average off the sound signature, I'll gladly sell him one.

LE and military roles for sound suppressors are vastly different in practice than civilian roles. I don't target just civilians with my products. LE and the military circles are a large source of revenue and repeat purchases. Civilians get the most benefits from a suppressor using a solid action (lever, pump, bolt, single shot) and subsonic ammunition. If these two aren't there, they will be disappointed to some degree.

PTK
February 25, 2009, 03:03 AM
There is little benefit to trying to suppress supersonic ammunition.

Civilians don't have much practical use for suppressing a supersonic cartridge.

:rolleyes:

Video link with contrary evidence (http://www.youtube.com/watch?v=7SIWkwO-ZhI) (filmed comparison between silenced/unsilenced 30-06)

David Hineline
February 25, 2009, 03:09 AM
Civilians don't have much practical use for suppressing a supersonic cartridge. The practical benefits are recoil reduction, muzzle blast reduction, some SPL reduction. Suppressors are more beneficial overall in the role of recoil reduction than a muzzle brake. A muzzle brake is the opposite of a suppressor.

This is one of the dubmest things I have heard a gun manuf. say.

First of Law Enforcement are civilians, any job that you can call in to at 8am and say I quit and am not comming back to work, without going to Federal prison is a civillian job.

What ever world you live in must not have prarie dogs or coyotes or crows or farmers who get 200 white tail deer permits a year to protect thier crops.
Having a silencer on makes the difference between shooting one animal, and shooting all of the animals. The flight noise of the supersonic bullet as it passes the animal if you missed often drives the animal in the shooter's direction as they did not hear a gun shot to run away from, but only the flight noise in the direction where the bullet passed them by, not the direction the bullet came from.

Varmint shooters shoot hundreds of rounds in a day, being able to do so without hearing protection messing up the cheekweld for the optic is a big benifit.

I have sold 20times the silencers to regular folks as compared to LE.
If you are going to base your business on the LE/Govment market you won't last long.

freakshow10mm
February 25, 2009, 09:57 AM
First of Law Enforcement are civilians, any job that you can call in to at 8am and say I quit and am not comming back to work, without going to Federal prison is a civillian job.
Dictionary.com:
ci⋅vil⋅ian
   /sɪˈvɪlyən/ Show Spelled Pronunciation [si-vil-yuhn] Show IPA
–noun
1. a person who is not on active duty with a military, naval, police, or fire fighting organization.
2. Informal. anyone regarded by members of a profession, interest group, society, etc., as not belonging; nonprofessional; outsider: We need a producer to run the movie studio, not some civilian from the business world.
3. a person versed in or studying Roman or civil law.
–adjective
4. of, pertaining to, formed by, or administered by civilians.

What ever world you live in must not have prarie dogs or coyotes or crows or farmers who get 200 white tail deer permits a year to protect thier crops.
Having a silencer on makes the difference between shooting one animal, and shooting all of the animals. The flight noise of the supersonic bullet as it passes the animal if you missed often drives the animal in the shooter's direction as they did not hear a gun shot to run away from, but only the flight noise in the direction where the bullet passed them by, not the direction the bullet came from.
I am in Michigan. Civilians cannot possess suppressors and there is no legal way to use one for hunting or damage control shooting. Yes there are coyotes and crows up here. Moot point as you can't use a suppressor for hunting nor rifles for crow. Are their benefits to using a suppressor on a supersonic rifle? Sure. To the best of my knowledge there are a handful of states that allow suppressors for hunting. Having that in mind, looks like target shooting is the only application, unless you can enlighten me with your omnipotent knowledge.

I have sold 20times the silencers to regular folks as compared to LE.
If you are going to base your business on the LE/Govment market you won't last long.
Most of my suppressors will probably end up in civilian hands. I can't sell direct to them in my state so they will have to go through SOT networks. My business isn't based off of government market, but some of my products are designed to fit the more demanding needs of that market. If dealers buy my products and sell them to civilian customers, good.

ZeSpectre
February 25, 2009, 10:07 AM
Okay folks, if you want to argue LEO vs Civilian and those definitions, or if you want to argue the "usefulness" of cans then please take it to another thread.

THIS thread is about the technical aspects of suppressor function.
-Durability
-Maintenance
-Effects on the rounds fired
and so forth.

Please haul this thread back onto topic or I'll ask the mods to close it 'cause I have no interest in the war that's brewing.

aroundlsu
February 25, 2009, 11:39 AM
Is it the suppressor or the ported barrel that reduces muzzle velocity on the MP5SD?

The ported barrel prevents the 9mm bullet from reaching supersonic speeds in the MP5SD. The suppressor has nothing to with it in this case.

David Hineline
February 25, 2009, 12:25 PM
Your questions are too general to answer well.

What holds true for a small silencer on a 22pistol does not apply to a full auto rated silencer for a belt fed machinegun.

Bartholomew Roberts
February 25, 2009, 02:15 PM
Is it the suppressor or the ported barrel that reduces muzzle velocity on the MP5SD?

My understanding is that the integral suppressor of the MP5SD is designed to work with the ported barrel/suppressor as a single unit. The gas bleeds off the ported barrel and into the suppressor. If that is the case, then it is kind of a "chicken or the egg?" question.

All of my experience is with shooting one and disassembling the suppressor was not something I ever did, so I couldn't speak to the technical aspects of it.

ZeSpectre
February 25, 2009, 02:19 PM
Your questions are too general to answer well.
My questions are as specific as I could get given my current knowledge level of almost nothing.

Basically I know that a silencer is a can with baffles sort of like a linear car muffler. Beyond that I'm trying to learn more out of simple curiosity.

So, in short, I've asked the best questions I know how to ask. :D

freakshow10mm
February 25, 2009, 02:36 PM
Get the Silencer: History and Performance Vols 1 and 2 and read them cover to cover.

Then wait patiently for Vol 3 to come out.:mad:

aroundlsu
February 25, 2009, 04:00 PM
All of my experience is with shooting one and disassembling the suppressor was not something I ever did, so I couldn't speak to the technical aspects of it.

From what I remember, the suppressor just screws off the front similar to any other screw on pistol suppressor. It looks like it could actually be shot without the suppressor attached but I don't know that for a fact.

Bartholomew Roberts
February 25, 2009, 04:17 PM
From what I remember, the suppressor just screws off the front similar to any other screw on pistol suppressor.

Well, the SD suppressor is detachable but without it attached, the ported barrel is going to be venting into the handguards. The SD suppressor is designed with the back section filled with a wire mesh - this is the part that the ported barrels bleed off into. Also the threads are on the back of the barrel (so the suppressor can fit over the ported section of the barrel), not the front.

RAnb
February 25, 2009, 06:23 PM
Here are some of my drawings and a photo.

http://img2.putfile.com/thumb/7/20217144286.jpg (http://www.putfile.com/pic/6068981)
This 510 whisper can is 2x18", very large. It telescopes over the last 6" of the barrel and makes a 950 grain bulllet moving 1050 fps sound like a car door slamming.

http://img2.putfile.com/thumb/7/18919290556.jpg (http://www.putfile.com/pic/5936814)

Drawing of the 510 whisper set up for the Encore and an Enfield modified to be like a Delisle carbine.

http://img2.putfile.com/thumb/7/18919290516.jpg (http://www.putfile.com/pic/5936815)

A 9mm silencer for my Browning HP.

All of these are easy to make on a hobby lathe from tubing and bar stock.

Ranb