suppressor increase velocity ?

[204cat]

suppressor increase velocity ?

was reading about barrel length 22 to 26 inches and how the affects muzzle velocity 100fps per inch on another caliber. was thinking < and yes it hurt like h3ll > that a suppressor would add velocity because of the extra length. maybe +25 fps per inch because of the openings inside the suppressor going to the baffles. but i would like some real testing or crono to show the data of how much increase or none. for the 204.

i know that use of a suppressor means that you will run subsonic ammo through the suppressor but i figure that two groups with the same loads or reloads would work. one group no suppressor and the other group with suppressor and compare the crono readings.

thank you for tolerating an odd thought or question.
204cat

i believe it dose but have no suppressor to test.

[NESHOOTER]

A suppressor would not add any FPS due to its design as it passes through the baffles and energy is bled off as in air leaving the barrel end the plus to the suppressor is that the muzzle blast is contained to a acceptable dcb's, and yes you still hear the supersonic bullet as it leaves the barrel.

[NESHOOTER]

I my self choose the 26'' barrel for its full use of energy but it depend more so on the burn rate of the said powder that one would be using, a longer barrel is what I choose and as I would use W-748, TAC, VARGET,EXTERMINATOR, or H-4198 and a crony charges of each powder and identical FPS listed vary as much a 350 fps between with the same 32gr bullet.

[NESHOOTER]

And by the way when you use a .223 suppressor on a .204 that really barks, the report/bang is less than a .22 believe it or not and when you fire and see your hit you hear the wonderful TWHAP. Because you don't need any ear plugs or protection.

[204cat]

as it passes through the baffles and energy is bled off

yes as the bullet passes through the suppressor energy is bled off. there is still push there as the energy decreases going through the suppressor. hence the question. was not sure if there was gain in velocity or not.

never had a suppressor on this 204. would go to trailboss powder to get subsonic first. if i did choose to get a suppressor i would at least get a 204 suppressor for a 204.

[Fred_C_Dobbs]

In the case of most "modern" suppressor design, yes, they will increase "muzzle" velocity by a few tens of fps. The phenomenon is known as freebore boost. The first chamber beyond the muzzle tends to "stack up" the gasses behind the bullet so they continue to drive it forward through the baffle stack.

[204cat]

i did not know the question already had been asked. if i had only looked in the suppressor section. i found some data on another board.

I've got a Remingon 5R with a 24" barrel. Liberty Freedom suppressor, 10" long.

Load is a 175 OTM, 42.5 gr Varget, Lapua Brass, WLR primer.

No suppressor velocity: 2600 fps mean.

With suppressor: 2615 fps mean.

All chonographed over an Oehler 35P.

Sako TRG-22
26" 308
Black Hills 180 Accubond Ammo
43 feet above sea level
86 degrees
70% Humidity
Shooting Chrony Alpha Master Chrono 10ft from muzzle
No can average - 2691fps
AAC Cyclone average - 2728fps

very slight out of rifles and less so out of pistols. But it does increase. I'd guess 20-30fps on rifles and 10-15 on pistols from what I've seen.

DPMS 16" carbine, 62 grain FMJ over 25.5 grains of H335:
2,959 fps without the can, 2,995 through a YHM 7.62 stainless Phantom

so looks like 20-40 fps per 6-8 inch suppressor.
thank you for the replies.

[Sidewinderwa]

There was an article in the Jan-Mar 2011 Varmint Hunter magazine and his test showed that suppressors did increase the velocity of the bullets. It was also interesting to find out that suppressors will reduce the recoil of the larger caliber rifles by up to 50%. I have a customer that ordered one for his 338 Lapua for that reason as well as reducing the blast to the ears. NESHOOTER, it is good to hear that a 223 suppressor will work on a 204. That will make it much more versatile to be able to move it between coyote rifles. They are pretty spendy!

[futuretrades]

never had a suppressor on this 204. would go to trailboss powder to get subsonic first.

My question here is, why would you want your 204 shooting at subsonic velocities. Seems to me there are other options for subsonic velocities, including the 22 rimfire. JMHO! My curiosity her has me baffled, but I am not being critical, just my own thinking. Besides, people with ideas is what has made this country, the best country in the world to live in!

[204cat]

to remove the supersonic crack from the bullet. not to scare the crap out of the live stock. i do not have a working 22 rimfire. to remove all bang from the discharge signature. was originally reading about barrel length when the question "does the suppressor increase velocity ?" occurred. was not even sure they make a suppressor for the 204. yes you are correct in that there are better choices for subsonic. i have no intent on purchasing a suppressor <if available for the 204> was more curious about the physics behind the question.

[Fred_C_Dobbs]

The supersonic crack isn't affected by the suppressor, only the muzzle report. There's a ton of hot gasses fighting to get out from behind the bullet, and they make a pop all their own once the bullet gets out of their way. That's all a suppressor controls. Once it's a foot downrange, the bullet won't know it ever was fired through a suppressor, and there's never yet been anything made by a human man that can travel through air at the speed of sound or beyond and not produce a sonic boom.

What's interesting about the sonic crack is it doesn't sound like it's coming from the gun, it sounds like it's coming from the target. Because the bullet itself is traveling faster than the sound it's making, you won't hear in until it has passed you. And your 'sense' will be that the noise's point of origin was in the direction of the bullet's ultimate point of impact.



These shadowgraphs are of bullets at differing velocities. If one of them came past you, no sound from it would reach you until the shock wave had. And by the time the shock wave hits you, the bullet is already long gone.

I know guys who hunt feral hogs in Alabama using suppressed ARs with light amplifying scopes. The hogs have no clue where the hunters are, even after they open fire. In fact, when they open up on a herd, the ones that haven't been shot in the first volley tend to flee away from the sound of the bullet, which means toward them, toward the hunters.

Notice also that the slowest bullet shown is making a wee little shockwave but it isn't quite going the speed of sound. That's because all flying objects will make a sonic boom from a certain airspeed upwards, and that certain speed -- called the critical Mach number -- always ALWAYS is below the speed of sound. Gun writer Al Paulson, who is regarded as the dean of silencer experts, did systematic testing and found all bullets continue to create a shock wave -- and supersonic crack -- down to 92-93% of the speed of sound. Maximum noise level is reached at -- IIRC -- 1.3x SoS.

So long as the the caliber is smaller than the one the can was intended for, the exact "fit" isn't that big a deal. .308 cans work very well on .223s, for instance.

But as far as removing the supersonic crack, there's only one way known to man to do that. Shoot it at a velocity less than it's critical Mach number.

[NESHOOTER]

Yes, it is great but just for the sake I even use a .308 cal suppressor on my .204...... to me it seem even more quiet. It maybe just me but the db's difference I am not able to distingush again to me only when were at the range and my dad shoot my .223 the POI are different and me hitting the bullseye is not so important to me when just shooting for technique and breathing.

[stef]

Have looked into suppressors but have been put off by the $250-$300 ? ATF fee, paper work, & wait. I might wind up with 28-30 inch barreled varmint rifle.

After a good varmint shoot I often hear the comment about how loud my rifle(s) were from nearby farmers (ranchers?) and they are not talking about cracking bullets.

Velocity and accuracy experiments with and without the suppressor sound interesting. There goes my 11 degree barrel crown.

[NESHOOTER]

Have looked into suppressors but have been put off by the $250-$300 ? ATF fee, paper work, & wait. I might wind up with 28-30 inch barreled varmint rifle.

After a good varmint shoot I often hear the comment about how loud my rifle(s) were from nearby farmers (ranchers?) and they are not talking about cracking bullets.

Velocity and accuracy experiments with and without the suppressor sound interesting. There goes my 11 degree barrel crown.

stef,
What it would ensue is a 200.00 ATF, 1time tax stamp fee. then the cost of the suppressor I use YHM the can cost 700.00 the .308 900.00 each Flashhider is 75.00 for each other rifle plus the cost of getting the barrel threaded, then the cost of getting the fingerprints and pic's the CLEO sign off that would allow you the right to send it to the ATF, if you don't go with a trust. Now in my home state Nebraska we have the option of Trust and doesn't require pic's,fingerprints, or a CLEO signoff, now the reason for the Trust is this it is written up as a corp/trust that allows other listed on the paperwork to also use and posses while using it not that they own it but is controlled as a say a time share. '' I am not a lawyer nor claim to have all knowledge'' Where as the normal ATF only allows you (1) to use and control the said class-III device.

I heard it said IF YOU CAN'T AFFORD THE BONE- DON'T GET THE DOG...LOL
The suppressor as stated above WILL REMOVE THE REPORT/BANG/BOOM and when you fire your .204, .223, .308, 30-06, 7mm mag, it is alittle more that a .22 when you shoot in the open field you hear no report. I shoot all my rifles with my suppressors even my little .22 it just as quiet as a sub-sonic report. I myself would never shoot any hunting round sub sonic unless close small game. not to mention ethical kills...

[Fred_C_Dobbs]

Not so much a factor with the .204 but I find the main reason I continue to use a suppressor is the reduction in recoil. Plus, it makes everything I put it on a tenth or two of a MOA more accurate.

But they are a PITA at public ranges. People tend to treat you either like you're a rock star or Tom Beringer in "Sniper." The extra attention gets real annoying real quick.