Suppressors suppressor velocity boost ? truth or myth ?

dvdt

Sergeant
Full Member
Minuteman
Sep 13, 2009
646
5
Dallas,TX
I've been reading about suppressors and the potential for increased velocity. I've seen it referred to a 'free bore boost' but I've also read people reporting no increase.

So, for you guys with suppressors, what's the verdict ? Is there a velocity increase ?

If you have numbers, can you please post along with details on your setup ?
Anyone have numbers with different suppressors compared on the same rifle and load ?
Is there a rule of thumb for increases ?
Is an 18" barrel + 8" suppressor equal to a 26" barrel ?
Does it depend on caliber?
Anyone tried this with a .260 Rem ?
Does type of rifle (bolt vs. gas) come into consideration?


I'd really appreciate some feedback.

Thanks!
 
Re: suppressor velocity boost ? truth or myth ?

I dont have the technical data recorded to support this, but on average, you'll gain aprox 25fps suppressed.You wont have huge gains adding an 8inch can to a 16 inch barrel versus adding barrel length.
 
Re: suppressor velocity boost ? truth or myth ?

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.

-David
Edgewood, NM
 
Re: suppressor velocity boost ? truth or myth ?

It mainly depends on the design of the suppressor.

Some of the older designs reduced muzzle velocity(E.G, old SMG cans), however most of the modern cans will give a little additional velocity. I know with many 5.56 cans on AR15s it tends to average about an extra 30fps. I would say its mostly a negligible change.
 
Re: suppressor velocity boost ? truth or myth ?

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

Black Hills lists 2550fps for this load, but I have no idea what rifle they used, if any, to get that number.

I'll try to get some data off my 10.5" 6.8 with my AAC M4-2000 and one of my 22 pistols and AAC Element in the upcoming weeks
 
Re: suppressor velocity boost ? truth or myth ?

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.
 
Re: suppressor velocity boost ? truth or myth ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CypressJeff</div><div class="ubbcode-body">
Is the FPS increase due to increased power burn before the projectile leaves the barrel?

</div></div>

no, free bore boost... when the bullets is still in the can, it still has the gas pressure behind it pushing, but no more rifling putting drag on it...
 
Re: suppressor velocity boost ? truth or myth ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dvdt</div><div class="ubbcode-body">I've been reading about suppressors and the potential for increased velocity. I've seen it referred to a 'free bore boost' but I've also read people reporting no increase.

So, for you guys with suppressors, what's the verdict ? Is there a velocity increase ?

If you have numbers, can you please post along with details on your setup ?
Anyone have numbers with different suppressors compared on the same rifle and load ?
Is there a rule of thumb for increases ?
Is an 18" barrel + 8" suppressor equal to a 26" barrel ?
Does it depend on caliber?
Anyone tried this with a .260 Rem ?
Does type of rifle (bolt vs. gas) come into consideration?


I'd really appreciate some feedback.

Thanks!

</div></div>

a .22 lr silenced .. slows down at the muzzle.
How much fps rate decreases in 1150