Shooting suppressed

Muleskinner said:

300 BO is more like a handgun round than a rifle round. I reload them, both sub and super and use pistol powder.

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All subs are like handgun rounds unless you are pushing 300+ grains of lead.

Muleskinner said:

300 BO is more like a handgun round than a rifle round. I reload them, both sub and super and use pistol powder.

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What powder?

Speedluvn said:

The above puts it all in perspective concerning suppressed.

Does anyone hunt with subsonic 300 BO rounds? I’ve had my 300 BO since April of this year and have only shot super sonic rounds until my last two visits to the range.

What have you done to reliably shoot subs in your firearm?

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From the beginning, an adjustable gas block. That and loading subs using A1680 powder and magnum(Rem 7 1/2 bench rest, in my case) primers.

Speedluvn said:

The above puts it all in perspective concerning suppressed.

Does anyone hunt with subsonic 300 BO rounds? I’ve had my 300 BO since April of this year and have only shot super sonic rounds until my last two visits to the range.

What have you done to reliably shoot subs in your firearm?

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My 9" Aero build will cycle 180gr subsonic loads just fine, 208s or 220s are no problem at all. Nothing special, just a 3oz buffer, standard spring, proper pistol length non adjustable gas system, and a minor buffing of the feed ramps. The caliber is no where near as finicky as 5.56, even when shooting supers suppressed, there is less gas than my 5.56 with the adjustable gas block turned for it. Where you tend to have to choke gas or increase buffer weight on 5.56, blackout usually needs as much gas as it can get. Shorter barrels also allow you to run a hotter load without going supersonic, most 300BO problems I've seen are 16" guns, especially with early 16"carbine gas barrels. A chrono is handy working g up loads, I've found some published loads calling for 1050ish FPS clock around 900 out of my 9" 300

dannyp said:

while on the subject , how much louder are supers than subs ? i know it's all relitive , your supressor and all , just courious .

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More gas making noise as well as the crack of the bulldog going supersonic.

For 22lr and a good suppressor a subsonic round out of a bolt gun produced in the range of 104-108dB of sound. A HV bullet produces between 118-122dB. That’s a bit more than 10x louder (sound is a logarithmic scale).

For the much larger and heavier bullet of a 300BO you are looking at probably around 114-120dB for a subsonic round with suppressor. Supersonic likely 130-140dB.

For a distant observer a subsonic suppressed 22lr you might not hear 100yds away over suburban background noise levels. For an HV 22lr suppressed it might take 200-300yds before you wouldn’t hear it at all.

For the 300BO that means about 200yds suppressed subsonic you likely wouldn’t hear. But supersonic it might still be audible at 500-600yds.

Now that’s “being able to hear”. It loud gun shot when you get close to those distances.

That’s assuming line-of-sight from listener to the source of the sound. Buildings, trees, etc will middle or more.

A regular gun shot is 155-170dB and could be heard more like 5+ miles away in open terrain.

lazarus said:

More gas making noise as well as the crack of the bulldog going supersonic.

For 22lr and a good suppressor a subsonic round out of a bolt gun produced in the range of 104-108dB of sound. A HV bullet produces between 118-122dB. That’s a bit more than 10x louder (sound is a logarithmic scale).

For the much larger and heavier bullet of a 300BO you are looking at probably around 114-120dB for a subsonic round with suppressor. Supersonic likely 130-140dB.

For a distant observer a subsonic suppressed 22lr you might not hear 100yds away over suburban background noise levels. For an HV 22lr suppressed it might take 200-300yds before you wouldn’t hear it at all.

For the 300BO that means about 200yds suppressed subsonic you likely wouldn’t hear. But supersonic it might still be audible at 500-600yds.

Now that’s “being able to hear”. It loud gun shot when you get close to those distances.

That’s assuming line-of-sight from listener to the source of the sound. Buildings, trees, etc will middle or more.

A regular gun shot is 155-170dB and could be heard more like 5+ miles away in open terrain.

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All those decibel references are meaningless.

Is that Peak Level, Leq, Peak Range, Maximum Level, A weighted, C weighted, Z weighted, unweighted...? At what distance and orientation to the muzzle were the measurements made? What diameter microphone?

GunBum said:

All those decibel references are meaningless.

Is that Peak Level, Leq, Peak Range, Maximum Level, A weighted, C weighted, Z weighted, unweighted...? At what distance and orientation to the muzzle were the measurements made? What diameter microphone?

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No, not meaningless. The question was asked how much louder are supers than subs, I know its all relative. So I gave RELATIVE numbers.

That is RELATIVELY how they compare. So no, you really don't need to compare all of that. I could get in to human ear response to various tones too if we REALLY wanted to get in to exact specifics. But that wasn't asked for, nor did I get in to that.

Just some range of magnitude stuff in comparison when running a can.

I didn't mention "no can", because I haven't looked a much of that, but from relatively limited experience with 22s and 300BO, as well as pistol calibers subs vs supers NOT suppressed, the volume difference is not all that high. With calibers that are riding the line of sub vs super anyway, its only a few dB difference. Noticeable if you fire a few supers and then a few subs, or mix them or whatever else. But it isn't like "oh that's really quiet, oh that's really loud".

For calibers where there is a HUGE difference in velocity, then supers are noticeably much louder, but the magnitude of difference is still not remotely like suppressed vs unsuppressed shooting.

I'll put it this way, the primary driver of the difference in most big boy calibers is the volume of gas being expelled and at what pressure is it uncorking at. For something like a 22lr, its generally only a difference of about 25% or so in muzzle energy between an HV and a subsonic round (yes I know ME and pressure in the barrel are not exactly comparable). So you'd expect there to be a minor difference in volume. Though the crack of a supersonic projectile, even an itty bitty one is fairly loud, but unsuppressed the crack is much quieter than the uncorking sound of the gunshot itself (unless suppressed).

Something like a 300BO the difference is about 33% of the ME of a supersonic round. So there is quite a bit of difference in volume, even not suppressed. The supersonic round is also a fair amount bigger and moving significantly faster so the super sonic crack is also a heck of a lot louder than the crack from a 22. But you are only in "noticeable, but not dramatic" differences in volume. It is still well past hearing safe (by comparison, some 22 bolt guns with longer barrels firing subsonic rounds actually ARE hearing safe if fired in open areas. I would not recommend it at all, because it is riding a fine line between hearing safe and not (HV 22lr is not hearing safe no matter the barrel length).

Suppressors capture a lot of the gas and gradually reduce the pressure so that the final uncorking pressure is significantly lower. Generally reducing the gun shot volume to ~1/100th what it would be (or even less). In some cases, the supersonic crack can be the primary audible component of the report and a suppressor can't really do anything about that.

Other things to consider are the platform. A bolt gun is going to be way quieter than any semi-auto. An AR is going to be louder than most other semi-autos, at least for the shooter (directing the gas back in to the action, in to the BCG is going to make it a lot louder at the shooters ear, than a gas piston gun will). There is also the noise of the action itself running.

Subs out of my 10/22 I don't feel like subjectively are much louder than the sound of the action running. But the bolt slamming backward, picking up a round and returning full to battery is NOT a quiet sound. Way quieter than an unsuppressed gunshot, but not quiet.

If you've never shot a single shot or bolt action 300BO suppressed you're missing out. I use my single shot, one tax stamp Encore a couple times a week to eliminate the groundhogs at a few local farms. I reload a 148 grain cast hollow point over Trail Boss for all my 150 yards and closer hunting areas. I load the new Hornady 190 grain Sub-X over CFE BLK for the areas that require me to lob in some longer shots.

This week I killed 7 at a local farm in about 2 hours. The two furthest shots were 305 and 308 yards (dialed 34moa with 100 yard zero). I missed on the first shot due to some wind at my back. Dialed down just a hair and took them both on the next two shots. The other 5 were between 107 and 238 yards with only one making it to his hole.

C.Alls said:

If you've never shot a single shot or bolt action 300BO suppressed you're missing out. I use my single shot, one tax stamp Encore a couple times a week to eliminate the groundhogs at a few local farms. I reload a 148 grain cast hollow point over Trail Boss for all my 150 yards and closer hunting areas. I load the new Hornady 190 grain Sub-X over CFE BLK for the areas that require me to lob in some longer shots.

This week I killed 7 at a local farm in about 2 hours. The two furthest shots were 305 and 308 yards (dialed 34moa with 100 yard zero). I missed on the first shot due to some wind at my back. Dialed down just a hair and took them both on the next two shots. The other 5 were between 107 and 238 yards with only one making it to his hole.

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That’s awesome. Good shooting too!

How is it one stamp, is that a brace or integral suppressor?

teratos said:

That’s awesome. Good shooting too!

How is it one stamp, is that a brace or integral suppressor?

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It's a 10" form 1 suppressor that I pinned and welded to a 9" Bull Berry barrel. I refuse to SBR anything due to the crazy expectations of having to notify the ATF if I want to travel out of state.

C.Alls said:

It's a 10" form 1 suppressor that I pinned and welded to a 9" Bull Berry barrel. I refuse to SBR anything due to the crazy expectations of having to notify the ATF if I want to travel out of state.

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Well done, sir.

A 16" suppressed 300 Whisper Contender loaded with a 220 grain round nose works great on deer. Less than 100 yards from the house my wife never notices the shot.

The Blackout is a rip off of the .300 Whisper .

The .300 Whisper was invented by J.D. Jones specifically to outperform the MP-5 SD with 147 subsonics .

Having done that , he then explored the hunting capabilities to seek extra markets for it , and found it did great . J.D. killed literally truck loads of Whitetails with subsonic 220-250 gr in testing .

Biggfoot44 said:

The Blackout is a rip off of the .300 Whisper .

The .300 Whisper was invented by J.D. Jones specifically to outperform the MP-5 SD with 147 subsonics .

Having done that , he then explored the hunting capabilities to seek extra markets for it , and found it did great . J.D. killed literally truck loads of Whitetails with subsonic 220-250 gr in testing .

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Actually it isn't. AAC was able to get the 300BLK in for SAAMI spec, because J.D. Jones chose not to do so for 300 Whisper. Same cartridge, yes. Rip off, no. In the end SAAMI spec rules the day.