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SILENCERS AND BULLET TRAJECTORY

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shooter4 View Drop Down
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    Posted: January/07/2011 at 10:58
Good day
 
Does a silencer afftect bullett trajectory?  Does it increase overall bullett drop? What about accuracy?
 
Really keen to learn more about the subject.
 
ThanksBreak Dance


Edited by shooter4 - January/07/2011 at 10:59
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SVT_Tactical Quote  Post ReplyReply Direct Link To This Post Posted: January/07/2011 at 11:03

No such thing as a silencer, there are suppressors though Wink.  Good ones will normally increase your accuracy.  The key to getting a good one is to find one with a REPEATABLE point of impact shift for when you shoot without the can and the with it. some will have zero, most will have some.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rancid Coolaid Quote  Post ReplyReply Direct Link To This Post Posted: January/07/2011 at 11:42
As stated, "suppressor" is a more accurate description.

A suppressor does not alter bullet velocity, so drop is the same suppressed or unsuppressed.

Point of impact shifts and accuracy changes (suppresed vs unsuppressed) are gun-specific and suppressor-specific, there are no hard, fast rules.

In general, I have found that shooting suppressed on my precision guns results in no change in precision and/or accuracy - or gives a slight increase in precision and accuracy.  There are a few basic reasons for this:

1.  Suppressors help diminish recoil, so you aren't anticipating the kick and jerking the trigger.
2.  When shooting unsuppressed, the bullet exits the muzzle in "turbulent" air; with a suppressor, the bullet exits in calmer air, which can enhance accuracy.
3.  Suppressors look cool, chicks like cool, no one wants to blow a shot when a hot chick is checking out their suppressed gun, so you tend to not blow shots so much.


Edited by Rancid Coolaid - January/08/2011 at 11:04
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SVT_Tactical Quote  Post ReplyReply Direct Link To This Post Posted: January/07/2011 at 11:48
Originally posted by Rancid Coolaid Rancid Coolaid wrote:

As stated, "suppressor" is a more accurate description.

A suppressor does not alter bullet velocity, so drop is the same suppressed or unsuppressed.

Point of impact shifts and accuracy changes 9suppresed vs unsuppressed) are gun-specific and suppressor-specific, there are no hard, fast rules.

In general, I have found that shooting suppressed on my precision guns results in no change in precision and/or accuracy - or gives a slight increase in precision and accuracy.  There are a few basic reasons for this:

1.  Suppressors help diminish recoil, so you aren't anticipating the kick and jerking the trigger.
2.  When shooting unsuppressed, the bullet exits the muzzle in "turbulent" air; with a suppressor, the bullet exits in calmer air, which can enhance accuracy.
3.  Suppressors look cool, chicks like cool, no one wants to blow a shot when a hot chick is checking out their suppressed gun, so you tend to not blow shots so much.
 
RC has hit the nail on the head with answer #3Bucky
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 338LAPUASLAP Quote  Post ReplyReply Direct Link To This Post Posted: January/23/2011 at 11:43
posters ???

Does a silencer affect bullet trajectory?  YES, all types regardless of Baffle or Wipe system
Does it AFFECT overall bullet drop? YES, all types regardless of Baffle or Wipe system.
What about accuracy?  YES, regardless of Baffle or Wipe system.

Any deviation from the normal "gun out of the box" will increase or decrease its accuracy. Threading, or changing muzzle-brake / flash-hider, cutting barrel length, making barrel extensions, or adding a suppressor to any firearm...


Can a suppressor affect Velocity...

ABSOLUTELY...

"FREEBORE BOOST"!!!

Thus affecting ballistics...

YES!!!!!!!

It will absolutely change impact point.  Maybe not tactical CQB impact point but long distance POI.

If not you are still to close to your PBR range or not shooting far enough or rather the change is very small and not as noticeable. 

Added velocity at shorter distances has less noticeable effect than at longer distances.

Maybe I need to go into more detail but if you think about the possibility of added velocity it will make sense that Trajectory will be changed as well as bullet drop and the result is more or less accuracy.




Edited by 338LAPUASLAP - January/24/2011 at 20:49
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tahqua Quote  Post ReplyReply Direct Link To This Post Posted: January/23/2011 at 11:56
I learn something here all the time. I had not heard of freebore boost. I did not know there was a SilencerTalk forum with over 22,000 members, either.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 338LAPUASLAP Quote  Post ReplyReply Direct Link To This Post Posted: January/23/2011 at 12:11

Question of definition.

It is not just limited to the area or space ahead of the bullet to which it has not yet made contact with the rifling, or when the ogive hits or makes contact with the rifling.

It was very well covered in a manual I use to have I am looking for an archive of it.

http://www.paladin-press.com/product/Silencer_History_and_Performance_Volume_1/Silencers







Edited by tahqua - January/23/2011 at 12:28
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: January/23/2011 at 19:18
For there being no such thing as a silencer there sure a lot of books at Paladin for making one at home. Must be an Escher,Bach,Godel meta topic. The Gizmos don't change stuff with the system themselves, but when compared with the "data" without the gizmos -- of course it changes it.
Curious about the freebore burst, thats a new one on me.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 338LAPUASLAP Quote  Post ReplyReply Direct Link To This Post Posted: January/23/2011 at 19:43
Originally posted by Dale Clifford Dale Clifford wrote:

For there being no such thing as a silencer there sure a lot of books at Paladin for making one at home. Must be an Escher,Bach,Godel meta topic. The Gizmos don't change stuff with the system themselves, but when compared with the "data" without the gizmos -- of course it changes it.
Curious about the freebore burst, thats a new one on me.


Dale I respect everything you post. 

The term silencer was well before the term suppressor, while incorrect it still preceded suppressor, Maxim was known for his silencer / muffler and even credited (USA) with its invention. I believe that Maxim called it a silencer or muffler. While we know it is not a true silencing apparatus it is still often referred to as a silencer.  (for those who wonder why silencer is incorrect).

The physics behind it are not to hard to grasp maybe the equation should not be tried by the uneducated but the concept is very understandable and is covered in great details in the book I made a link to…

I would not want to plagiarize in anyway or take content from someone’s work that is not my own.

It is not without understanding that I posted this.  This term was not coined without factual basis and much scientific research has gone into understanding the phenomenon.  Most SUPPRESSOR or silencer manufactures try to reduce this by porting the attachment point or the suppressor/silencer internally to allow for gas and pressure relief that coincides with rifling twist and bullet spin however no manufacturer that I know of has eliminated the physical problems of this. 

I am sure other terms can more accurately describe the air movement and collisions that occur or happen when the bullet travels through the wipes or baffles. 

I had a few class room hours on this topic.  And was given the above mentioned book in MOS training for rack time.  I can only remember one reference of the velocity change and point of impact change that was not called free-bore boost or burst, it was called a greater unexplainable indefinite velocity change or something close because we all discussed how ambiguous that was.

I am also stating that many do not notice this as it usually only results in Velocity Difference that is unknown without measurement or a long distance impact change.

Adding a suppressor or anything Muzzle-Brake Flash Suppressor/ Flash hider also changes barrel harmonics.  But a 4"-18" steal or ti suppressor weighing 4oz-30oz certainly adds to that part of the equation.

The usual deviation for short range is less than a 1/2 or 1/4MOA point of impact shift which to most is not measurable due to inconsistencies of the shooter.

Off a bench rest or support you can scientifically watch this occur.

Temperature is a very big variable in this equation as velocity will change as heat is affecting all aspects of the equation.

Not to be too long winded,  Not that if you read it on the net it has to be true but I am sure you can Google it.  THE BOOK above mentioned is very appropriate.

And the military manual that was declassified the other is classified.


Thanks KickBoxer for the assistance...


Declassified Manual

http://www.paranormalhappens.info/US%20Military%20Manuals/Silencers%20-%20Principles%20and%20Evaluations.pdf

pg 145-157












Edited by 338LAPUASLAP - January/23/2011 at 22:20
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: January/24/2011 at 10:08
I think the current popularity in calling them supressors is more of politically correct term to avoid the hollywood image of criminal use..
The formulas above are the Ideal Gas Laws and the Work gas law rearranged to reflect the changes caused by increases of volume, then using the work law to calculate  PV=mRT to calculate the amount of work in any expansion chamber. The difficulty of this is finding out the value at any given pt. along the axis of the barrel. It is much easier and more informative to calculate the surface area from caliber, x barrel length and measure the pressure by tranducers along the barrel, this will give you a Poisson distribution for any caliber, (what your really after is the initial or highest pressure), calculate the force at that point in newtons, and integrate force equation which give you the work avaiable to be done on the system . This book wasn't written when todays computers were around, but are accurate as an algebraic counterpart.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rancid Coolaid Quote  Post ReplyReply Direct Link To This Post Posted: January/24/2011 at 11:22
We might want to break the conversation up into "cold bore" vs. "warm bore", as the effect seems to vary widely based on the temperature of the air in the can.


I guess my summary statements above should have been more specific.

Most of my suppressed fire is:
A. from precision rifles, slow fire (can is ambient or slightly elevation, but not hot.)
B. Semi auto, can might be hot, but am firing off-hand or from positions other than extremely stable.


Hot air in the can makes sense, ambient air in the can has little effect.


Edited by Rancid Coolaid - January/24/2011 at 12:39
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 338LAPUASLAP Quote  Post ReplyReply Direct Link To This Post Posted: January/24/2011 at 12:15

I think we need to understand the "turbulent air" and the collisions that occur that cause the bullet to be pushed forward or propelled "inconsistently" for instance the same formula does not apply say 1" = 30 fps and so forth you have to understand it is an indeterminate amount because of the effects of change.

 
The warm vs. hot is important but I am speaking about or referenceing only the gas or turbulent air and how it adds velocity due to bounce back or diflection off the baffles even while not being entirely sealed or as affecting as the bullet in the bore, but rather still being pushed.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rancid Coolaid Quote  Post ReplyReply Direct Link To This Post Posted: January/24/2011 at 12:41
For me, this needs some experimentation.  As I said, from my precision rifles, I looked more at POI shift (w/ vs w/o can) and long range dope.  

Very interesting.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 338LAPUASLAP Quote  Post ReplyReply Direct Link To This Post Posted: January/24/2011 at 21:24
To all:
Suppressors can be just as efficient as muzzle brakes in terms of recoil reduction. Because suppressors are designed to capture propellant gases and release them slowly into the atmosphere, the usual "punch" of high-velocity gases against the weapon's muzzle are reduced to what could be called a "push." Also, the sheer mass of the suppressor will help to reduce movement at the muzzle. Muzzle brakes, on the other hand, actually increase a shooter's exposure to harmful sound pressure levels by directing muzzle blast back toward the shooter.

The phenomenon known as "freebore boost" occurs in particular suppressor designs and sometimes requires a particular loading of ammunition. It is caused by a primary expansion chamber ahead of the barrel's muzzle which acts as a barrel extension as a bullet passes through it. Propellant gases continue to expand inside the chamber and push the bullet through the baffle stack at a slightly increased velocity. The suppressor can actually increase bullet velocity up to about 40 feet per second (12.1 m/s) depending on the design.

Any weapon with a suppressor attached will have a substantially different zero (point of impact) from when the suppressor is not attached. This is due largely to the mass of the suppressor altering the harmonics present in a barrel when a shot is fired. Fortunately, the suppressed zero is usually repeatable. This cannot be avoided. Tandem aiming devices or a device which can calculate two points of impact will be necessary if the weapon is to be used both with and without the suppressor attached.

Any automatic weapon with a suppressor attached will have an increased rate of fire due to the fact that a suppressor is designed to contain propellant gases. This has the effect of increasing pressure within the weapon's operating system, so increasing ROF. Some types of operation (particularly blowback operations) are more sensitive to this effect than others.

Because a suppressor contains propellant gases, it also contains and absorbs heat. As a consequence, barrel heat dissipation happens at a slower rate. In conjunction with side effect #4, these effects translate to increased barrel wear.

Suppressed weapons need to be cleaned more often due to the fact some of the propellant sediment is forced back into the weapon's action by the suppressor.


possibly the easiest read i have found


http://10gauge.de/raygun/basics/suppress.html


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Post Options Post Options   Thanks (0) Thanks(0)   Quote 338LAPUASLAP Quote  Post ReplyReply Direct Link To This Post Posted: February/06/2011 at 23:02
Anybody test this yet???  Nothing better than the silence in the snow makes me want to move to Alaska....

Remember decreased chamber pressure decreased velocity cold air is more dense and the bullet will be slower as the barrel and chamber heat up so will velocity.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 338LAPUASLAP Quote  Post ReplyReply Direct Link To This Post Posted: April/30/2011 at 19:45
Rancid done any tests yet???
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 338LAPUASLAP Quote  Post ReplyReply Direct Link To This Post Posted: March/24/2016 at 21:26
Man I miss these!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rancid Coolaid Quote  Post ReplyReply Direct Link To This Post Posted: March/25/2016 at 09:06
You are in a nostalgic mood today, huh?

I'm not sure what was on the now gone links, but the NFA does in fact call them silencers, not suppressors (though they suppress, but do not silence.)
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I had to find some sanity last night and the best way for me to ground myself is to read things like this.

Man the good old days...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Steelbenz Quote  Post ReplyReply Direct Link To This Post Posted: March/25/2016 at 11:58
I am in process of buying 2 cans, a Saker 762 and a Shepherd 45. Once they are out of the gulag I want to try this out!
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