Sound Suppressor Question

[Joe Chartreuse]

If this belongs elsewhere, Mods please be kind enough to move.

I recently discovered that one of my rifles has a threaded barrel that I was not aware of. The cover seam is almost invisible.
This got me thinking about getting a suppressor for it. Unfortunately, they are illegal in NJ unless you have some sort of special deer population control permissions blah blah yada yada.

Strangely enough, they are easily bought and perfectly legal a short drive away over the PA border. Of, I would never even THINK about making the drive for a purpose such as that because it's wrong......

All of that aside, I have no experience with suppressors and questioned how they might affect accuracy. I am completely confused by the answer: The would probably add accuracy for tighter groupings, but the POI could be 2-3 off where one would expect the hit. I tried for an explanation and got information regarding "barrel harmonics" and my brain seized up. Can anyone explain it like I'm 5?

Again, this is just for purposes of personal knowledge because I don't live in Pennsylvania even though it's so close.

 

[NikA]

Regarding your PA statement, the ATF will not approve a suppressor application in a state where they are not legal (AFAIK). Since you have to provide your residence information on the application, there is no "driving across state lines to acquire" possibility.

 

[hittman]

https://www.rugerforum.com/threads/a-new-toy-was-delivered-yesterday.329746/unread

Maybe info here will help

 

[Joe Chartreuse]

Regarding your PA statement, the ATF will not approve a suppressor application in a state where they are not legal (AFAIK). Since you have to provide your residence information on the application, there is no "driving across state lines to acquire" possibility.

Actually, in PA all you need is an FFL. Nothing else. No application, just show them the numbers. HOWEVER, NJ makes it illegal to carry it over the state line. Thing about PA- they don't give a damn. One can get anything there. I have seen a 32 load barrel mag for an LCP over there.

 

[Joe Chartreuse]

https://www.rugerforum.com/threads/a-new-toy-was-delivered-yesterday.329746/unread

Maybe info here will help

It's cool, but doesn't explain the reason for the accuracy discrepancy.

 

[JAYDAWG]

I know WHY, but my explanation would sound like a 5 year old wrote it........
So, I found this online ...............

Why POI Shift Happens (The Short, Simple Science)​

POI shift happens because adding a suppressor changes how the barrel and rifle system behave during the firing cycle. The causes are mechanical and predictable, not mysterious.

When a rifle is fired, the barrel vibrates. These vibrations, known as barrel harmonics, influence the exact angle and timing of the bullet as it exits the muzzle. Adding a suppressor changes the vibration pattern by adding weight and altering the way the barrel oscillates.

Even small changes in vibration timing can result in a measurable shift at the target, especially at longer distances.

Suppressors add mass to the very end of the barrel. This changes the balance and increases the barrel’s leverage during recoil. Lighter-profile barrels tend to show more noticeable POI shifts than heavier barrels because they are more sensitive to added weight.

For this reason, lightweight hunting rifles often display more shift than precision rifles with thicker barrels.

 

[Mobuck]

Adding 12-20 ounces to the muzzle MAY affect accuracy and quite likely WILL affect POI. There's no mystery about this--as mentioned, it's barrel harmonics. Generally speaking, the thinner the barrel profile, the more or more likely this extra weight will have some effect.
Last year my older Son tried three different rifles in an attempt to find a 'perfect match' for suppressor use. He wasted quite a bit of time and ammo mostly because he was trying to find a long, skinny barrel that wasn't adversely affected by adding a suppressor. My rifle (same caliber) with a slightly shorter and thicker barrel was just 'plug and play' simple.

 

[s4s4u]

32 load barrel mag

 

[s4s4u]

Folks obsess over the crown of the muzzle of a rifle, because it is the last thing that affects the bullet as it leaves the barrel.

A suppressor adds a bunch of baffles to the equation, AFTER the bullet has cleared a "clean" crown. It would make sense that those series' of baffles just MIGHT affect the flight of the bullet...jus sayin...

 

[M118LR]

A properly timed can will shift POI consistently. So you will need to annotate POI/POA with the can on or off. If your optic can track reliably it only requires a few turns on the turrets. The easiest way to explain it: POI/POA are going to change when you add weight at the end of the barrel. How much weight and how thin the barrel determine how much POI is going to move. As long as it's properly timed it can be easily adjusted for and then return the settings back to original without suppression. KISS. Just do a box test on your optic to see if it tracks properly prior to adding a suppressor. JMHO YMMV.

Remember when Ruger added a weight to the end of the Mini-14 barrel to improve accuracy?

 

[Joe Chartreuse]

I know WHY, but my explanation would sound like a 5 year old wrote it........
So, I found this online ...............

Why POI Shift Happens (The Short, Simple Science)​

POI shift happens because adding a suppressor changes how the barrel and rifle system behave during the firing cycle. The causes are mechanical and predictable, not mysterious.

When a rifle is fired, the barrel vibrates. These vibrations, known as barrel harmonics, influence the exact angle and timing of the bullet as it exits the muzzle. Adding a suppressor changes the vibration pattern by adding weight and altering the way the barrel oscillates.

Even small changes in vibration timing can result in a measurable shift at the target, especially at longer distances.

Suppressors add mass to the very end of the barrel. This changes the balance and increases the barrel’s leverage during recoil. Lighter-profile barrels tend to show more noticeable POI shifts than heavier barrels because they are more sensitive to added weight.

For this reason, lightweight hunting rifles often display more shift than precision rifles with thicker barrels.

Got it, and NOW completely understand. This has been bugging me for awhile. THANK YOU for killing the brain worm. ;-)

 

[Joe Chartreuse]

Yup. But where did you find my picture?! ;-)

 

[GYJ44]

Actually, in PA all you need is an FFL. Nothing else. No application, just show them the numbers.

Uh, what?

 

[Mobuck]

"A suppressor adds a bunch of baffles to the equation, AFTER the bullet has cleared a "clean" crown."
BUT Those baffles don't 'touch' the bullet and in a properly machined suppressor are concentric with the bullet's flight.
I have a matched pair of 6.5 Creedmoor rifles set up as primary and backup suppressor hosts. Both have the same muzzle mount and both are closely matched for accuracy. Even though the YHM suppressor doesn't affect POI much, I can reduce the affect to nearly nothing by adding a YHM 'blast deflector' which weighs about 1/3 as much as the actual suppressor to the backup rifle. The unsuppressed back up rifle can be used with the deflector or the deflector removed and suppressor installed w/o a noticeable change in POI.
My point is: sometimes it doesn't take much to quiet those muzzle vibrations and sometimes different weights produce similar results.

 

[willk]

Funny thing about places. In some of the most serious gun control nations, it’s practically illegal to shoot WITHOUT a suppressor. In some of the states of a nation with a 2nd amendment it is NOT legal to even own a suppressor. Say what you like about Louisiana, They don’t mess with you here unless you mess with them.

To the question at hand, in my limited experience, anything you do to a barrel can and usually will affect point of aim. For most applications the change may be negligible. For precision purposes such as bench rest, F Class or PRS, it’s best to reset the zero and check dope.

To explain

Guns are funny things. Once I experimented with a 7mm 145 grain Speer SBT in my XP100. I had been using Sierra 140 grain MatchKings. Accuracy was more than acceptable with the Speers’s but impact shifted almost 7 inches at 100 meters. However, in my old 6.5 barrel in my MPA Production rifle, shooting 130 grain Berger VLD’s and 130 grain Sierra CT MatchKings, which took .5 grains less powder. Both bullets landed at the EXACT point of aim. So, I realize this is off the subject, but used as an illustration as to how small things can change or may not change.

So, the point, If you can actually obtain and use one, experimenting with the suppressor can be part of the fun. But hard to believe the laws and regulations of some of these “states.”

 

[kmoore]

The last 3 years I have purchased 3 suppressors and since have sighted in 8 different centerfire and 2 rimfire rifles. They all did change the point of impact. Groups, I haven't noticed a difference in size.

 

[Yaworski]

Actually, in PA all you need is an FFL. Nothing else. No application, just show them the numbers.

Don't think so. An FFL is still going to want the appropriate ATF paperwork.

 

[soupy]

Gents,
I have a home in Pennsylvania . Pay full taxes just like everyone else plus bank accounts and the Mortgage was in a local bank. I also have a home in NJ. I vote in NJ-my driver's license is in NJ. But my wife and I split our time between the 2 states. We don't rent either home. Even have a whole house generator, run on propane!
Can I get a suppressor and leave it in the safe in PA? Would a trust application be easier. Naturally I'm looking at the situation as a citizen trying to exercise my rights.
What's the general consensus? Say ye NAH?
Semper Fidelis
Soup

"Down South 68-69"

 

[blume357]

I do have to take issue with something the OP said... he wrote that it was 'wrong' for him to go to PA and get a suppressor .... I say it might be illegal but that does not make it 'wrong' a lot of things have been and still are illegal that in my opinion are not 'wrong'.

I don't think you can get around it because of the ID issue but keep in mind if you have a vacation property in another state then according to the ATF while you are in that state you are a resident of that state.

 

[RoninPA]

Gents,
I have a home in Pennsylvania . Pay full taxes just like everyone else plus bank accounts and the Mortgage was in a local bank. I also have a home in NJ. I vote in NJ-my driver's license is in NJ. But my wife and I split our time between the 2 states. We don't rent either home. Even have a whole house generator, run on propane!
Can I get a suppressor and leave it in the safe in PA? Would a trust application be easier. Naturally I'm looking at the situation as a citizen trying to exercise my rights.
What's the general consensus? Say ye NAH?
Semper Fidelis
Soup

"Down South 68-69"

Soupy, you are what is considered by the BATFE as a two state resident (as long as you own a residence in PA and pay PA real estate taxes). When you are living in PA you are considered by both PA and the BATFE to be residents of PA and fall under the PA firearms laws. That means that you can buy and own any firearms and such just like any other PA resident. The only thing is that if the firearm item you buy is not allowed in NJ, it must stay in PA while you are away from your PA residence. I am a FFL/SOT in PA and have several individuals from NY who also live in PA part time and have NY DL's and they have purchased firearms, suppressors and even a full auto firearm through me (and the BATFE/NFA Division for the suppressors and the full auto) with no problems at all.

 

[Joe Chartreuse]

I know WHY, but my explanation would sound like a 5 year old wrote it........
So, I found this online ...............

Why POI Shift Happens (The Short, Simple Science)​

POI shift happens because adding a suppressor changes how the barrel and rifle system behave during the firing cycle. The causes are mechanical and predictable, not mysterious.

When a rifle is fired, the barrel vibrates. These vibrations, known as barrel harmonics, influence the exact angle and timing of the bullet as it exits the muzzle. Adding a suppressor changes the vibration pattern by adding weight and altering the way the barrel oscillates.

Even small changes in vibration timing can result in a measurable shift at the target, especially at longer distances.

Suppressors add mass to the very end of the barrel. This changes the balance and increases the barrel’s leverage during recoil. Lighter-profile barrels tend to show more noticeable POI shifts than heavier barrels because they are more sensitive to added weight.

For this reason, lightweight hunting rifles often display more shift than precision rifles with thicker barrels.

THANK YOU, and thank all for your replies.

 

[Jakeintexas]

Gents,
I have a home in Pennsylvania . Pay full taxes just like everyone else plus bank accounts and the Mortgage was in a local bank. I also have a home in NJ. I vote in NJ-my driver's license is in NJ. But my wife and I split our time between the 2 states. We don't rent either home. Even have a whole house generator, run on propane!
Can I get a suppressor and leave it in the safe in PA? Would a trust application be easier. Naturally I'm looking at the situation as a citizen trying to exercise my rights.
What's the general consensus? Say ye NAH?
Semper Fidelis
Soup

"Down South 68-69"

ATF considers you a part time resident of a state you have a residence in for the time period you are there.

Fr’ instance if I had a residence in TX and NJ and a NJ license (not sure why anyone would do something like that) ATF considers me as a part time resident of TX while I’m there. I could easily buy a firearm through a private transaction and be perfectly legal.

Problem is it’s unlikely a FFL would do a transfer without a state DL. If you did have some form of TX ID that an FFL can accept with a TX address then you wouldn’t have any problem. A TX CHL with a TX address methinks would work.

 

[XUSNORDIE]

"32 load barrel mag"

He's probably using the wrong nomenclature to describe the 32 round drum mag that is available for the LCP. Gimmicky but available.

 

[Joe Chartreuse]

"32 load barrel mag"

He's probably using the wrong nomenclature to describe the 32 round drum mag that is available for the LCP. Gimmicky but available.

Yup.... No idea why I typed "barrel" - meant drum. My oops. The thing weighs too much when full for that little gun.

 

[RoninPA]

There is no requirement (or anywhere) on the Form 4 for a drivers license to be entered. If a person is a part time resident, they need to give the FFL/SOT a copy of something that proves they have a residence in that state. The BATFE/NFA Division recommends a copy of the most recent real estate property tax document which will show the physical location of the property/home and the name of the owner. A DL in this case is just used as an ID card to prove that a person is who they say they are and to validate the name on the property tax form. I have done multiple Form 4's for customers who are part time PA residents and live in NY and have a NY DL. They provide me with a copy of their PA real estate property tax statement which I keep on file, as it does not get attached to the Form 4 (nor is there anywhere to attach it). The NFA Division does a background check on the person applying for the (suppressor, short barreled rifle, short barreled shotgun or full auto firearm) from the information on the Form 4. Basically they do a National Instant Check System (NICS) background check and if the person passes they put the tax stamp on the form and email (for a eForm4) or mail (paper copy Form4) it to the FFL/SOT and the buyer finishes any state law requirements and leaves with their new "toy" and the tax stamp paperwork.

Oh, yeah, None of my PA/NY customers have ever had a Form4 or eForm4 disapproved.

 

[John Andrews]

I know WHY, but my explanation would sound like a 5 year old wrote it........
So, I found this online ...............I have three rifles I shoot suppressed and they all are very accurate.

Why POI Shift Happens (The Short, Simple Science)​

POI shift happens because adding a suppressor changes how the barrel and rifle system behave during the firing cycle. The causes are mechanical and predictable, not mysterious.

When a rifle is fired, the barrel vibrates. These vibrations, known as barrel harmonics, influence the exact angle and timing of the bullet as it exits the muzzle. Adding a suppressor changes the vibration pattern by adding weight and altering the way the barrel oscillates.

Even small changes in vibration timing can result in a measurable shift at the target, especially at longer distances.

Suppressors add mass to the very end of the barrel. This changes the balance and increases the barrel’s leverage during recoil. Lighter-profile barrels tend to show more noticeable POI shifts than heavier barrels because they are more sensitive to added weight.

For this reason, lightweight hunting rifles often display more shift than precision rifles with thicker barrels.

 

[John Andrews]

My suppressed Ruger American gen 2 5.56 rifle, my suppressed Savage A17 .17 WSM, and my suppressed Savage BMAG .17 WSM skinny barrel are all very accurate.