Looking for a Subsonic Carbine for pest control

[old303]

Pistols are only loud because of the short barrel. But stick any of those pistol cartridges in a rifle length barrel and you'll find a substantial change in the tonality and loudness of the muzzle blast.

Factory ammo is going to be made to a typical firearm for that cartridge. So pistol ammo is expecting a short barrel and the powder should be fully burnt up by the time it leaves a rifle-length barrel, or even worst case leave you needing the squib rod. Over on the far corner of the chart, rifle ammo in a short barrel is how you get a nice fireball of still-burning powder out the muzzle!

The other thought is that a semi needs ammo that comfortably cycles it, but a single-shot or manual repeater can take very mild handloads with far less noise than nominal factory ammo of that size.

 

[Meroh]

Pistols are only loud because of the short barrel. But stick any of those pistol cartridges in a rifle length barrel and you'll find a substantial change in the tonality and loudness of the muzzle blast.

Quiet my a***; PCCs are allowed in our indoor pistol range, they are not as quiet as the equivalent cartridge fired from a pistol... speaking from experience.

Like I said, there is no free lunch.

Trying to justify a new purchase to the wife? Use it once, and she will know.

Stick with .22

 

[Baked Potatoe]

Good good observation. A pistol or a revolver with a short barrel less than 4 inches. it’s going to be a lot closer to your head so that’s why it’s gonna be perceived louder there. That same cartridge travelling through a longer barrel will have time to accelerate and will actually leave the barrel faster. The sound will merely be farther away from your head for the perceived noise. A barrel does not absorb noise.

 

[I Dont Care About You]

That same cartridge travelling through a longer barrel will have time to accelerate and will actually leave the barrel faster.

This is not strictly true. A long barrel can result in less velocity when friction exceeds the push from the gas pressure. This is a well known phenomenon in long barrelled rimfire rifles.

A barrel does not absorb noise.

Also not strictly true. A longer barrel results in a drop in gas pressure due to an increase in the bore volume as well as a cooling of that gas, which also reduces the pressure. The same amount of gas being released at lower pressure will indeed result in less noise. Its just basic physics

 

[I Dont Care About You]

Hey Mods

Maybe DON'T disappear posts because there is a difference of opinion? We are adults and can handle differing opinions.

I don't really care that some guy was condescending to me. I do care that an exchange of information is being disrupted by a moderator for no good reason. I was hoping to learn something about where certain information / data came from and how it was collected. That helps me understand how our physical world works. I am very interested in the actual flight noise generated by supersonic projectiles. IF the data posted is factual then I have learnt something. IF the data posted was complete baloney then we all learn something as well.

Please restore the multiple posts that were deleted because someone not even involved in the conversation got their panties in a bunch.

 

[boxhitch]

How loud would a sub caliber insert, (410, 357, 9mm, etc) in something like a Browning 34" BT99 be?

View attachment 1208037

interesting question. That short insert leaves a lot of room in a long barrel for gas pressure and velocity to cool off before the muzzle.
?? Would like to see actual test data

 

[Murray 3-D]

Another vote goes to .38spl. Such a pleasant sub 100m varmint round. I load 12 cent copper plated 158gr bullets over 4.0grs of Titegroup powder (just above max book charge for .38pl, and into the +P spectrum). Fired out my 18" barreled Uberti 1873 lever action those loads chrono at around 850-920fps. The longer barrel most certainly decreases the velocity as 16" trappers with the same load are supposedly getting closer to 1000fps.

Id expect most factory loads to shoot the same or under that. So out of a long barrel all standard weight (158gr) .38spl are likely guaranteed to be tame.

Accuracy is decent by pistol cartridge standards. I pretty reliably get 2moa at 50m.

Because the bullets are .357" in diameter they still have tons of varmint grade lethality out to 100m (I mainly shoot porcupines). Random shots without earpro are still likely in the harmful range (most stuff is). But it certainly doesnt seem to agitate my hearing like other centerfire guns. Id rate it maybe twice as loud as .22lr ?

 

[I Dont Care About You]

interesting question. That short insert leaves a lot of room in a long barrel for gas pressure and velocity to cool off before the muzzle.
?? Would like to see actual test data

A few years back there was a trend of guys adding a long "choke" extension to their shotgun ... like 24+ inches long. That unwieldy contraption significantly reduced the muzzle blast to a point where it was hearing safe for the shooter.

https://www.reddit.com/r/Gun####/comments/5qh3j0/silent_without_a_suppressor_32_inch_metro_gun/

 

[Murray 3-D]

Quiet my a***; PCCs are allowed in our indoor pistol range, they are not as quiet as the equivalent cartridge fired from a pistol... speaking from experience.

Like I said, there is no free lunch.

Trying to justify a new purchase to the wife? Use it once, and she will know.

Stick with .22

Physics disagrees.

 

[SHELL SHUCKER]

A few years back there was a trend of guys adding a long "choke" extension to their shotgun ... like 24+ inches long. That unwieldy contraption significantly reduced the muzzle blast to a point where it was hearing safe for the shooter.

https://www.reddit.com/r/5qh3j0

Those Hastings Metro barrel extenders work well for folks at trap ranges in crowded areas with noise restrictions. I tried a few shots from
a Browning Gold wearing one. They definitely drop down the noise level at the muzzle and are actually nice for maintaining a good swing
and follow through when shooting clays.
https://www.hastingsdistribution.com/index.php?l=product_detail&p=101

interesting question. That short insert leaves a lot of room in a long barrel for gas pressure and velocity to cool off before the muzzle.
?? Would like to see actual test data

Ye be correct on that. I had a 12 ga insert adaptor for 38 Special that I played with eons back in a couple of my guns. They made more of
a bloop sound than a bang when firing.

 

[Meroh]

A few years back there was a trend of guys adding a long "choke" extension to their shotgun ... like 24+ inches long. That unwieldy contraption significantly reduced the muzzle blast to a point where it was hearing safe for the shooter.

https://www.reddit.com/r/5qh3j0

I'll take your word for it, but what about the guy in the next county?? LOL

 

[Meroh]

interesting question. That short insert leaves a lot of room in a long barrel for gas pressure and velocity to cool off before the muzzle.
?? Would like to see actual test data

How accurate would it be?

 

[I Dont Care About You]

Because the bullets are .357" in diameter they still have tons of varmint grade lethality out to 100m (I mainly shoot porcupines). Random shots without earpro are still likely in the harmful range (most stuff is). But it certainly doesnt seem to agitate my hearing like other centerfire guns.

Even low velocity 38 Sp will still meter in the 150-155 dB range. Hearing safe is 140 dB.