I understand that baffles are designed to hold the gasses as long as possible in order to cool before exiting the can, the more swirl the better. Flat washers are the worst with cones, M, B and K baffles being much better. Has anyone been able to conduct a test and put numbers to actually estimate difference? I would assume one could take a can, have different baffles for it and test the difference. I know that some baffles may be better for specific applications and results will vary slightly. All I have been able to find after digging for a couple days is either comparisons of completely different cans or “It sounds quieter” statements after putting new style baffles in an old can. Yet no actual tests to put estimated numbers on the difference.

Thank you

The problem is nobody can do this (without paying $200 per baffle) other than the manufacturers, and they aren't going to be publishing their R&D results.

The best anyone can do is ask for help with specifics.

For instance, K baffles perform excellent with low pressure pistol calibers but don't perform as well in high pressure rifle caliber applications.

If there are specific questions you have, ask away, but you are likely to not get much help with generic differences as there are too many variables involved

That makes sense,


    So I am currently waiting on my Form 1 for an SBR to come back. I am planning on suppressing it but since this if my first NFA purchase with the Trust I want to make sure the SBR goes well before jumping the gun on more. This also gives me time to do some research. What I am attempting to do is figure out cost vs efficiency. All I am trying to do is eliminate muzzle flash for my NVGs and not ring my ears (night hunts). It appears that I can turn steel flat washer into cone baffles much cheaper than machining other types of baffles and I assume it would be effective enough.  I will be running on a 300AAC 8in upper and I would feel more comfterable with supersonic loads for so that the ammo will never be my limit on any distance if needed during day or night.  

I bought these from the same seller (amazon.com link). They are only twice as expensive as standard freeze plugs and are pre-formed at an angle. I don't know exactly what the angle is but it's at least 40 degrees. They are center punched, also.

I will be building my first can soon, and I am just going to stick as man baffles as I can in there.  Its not rocket appliances.  

I would bet the big name makers have tested the DIY stuff and you do know if there suppressors were WAY better you would see results posted. But if its only a 3 DB difference why would they ever disclose that.

Most manufactures have done that and you see the results in the products on the market.  Close stacked cones work better for centerfire rifle rounds and K Baffles have a slight edge in rimfire/pistol/anything-subsonic.

PIstol or Rimfire I would hope, that ID is a bit small for centerfire rifle rounds.

It’s what will fit inside of my Troy hand guard - ID of 1.39- should I make it longer to compensate maybe 1in?

If you understand how a muffler works on a car, then apply the same thought process to a can. For instance the more baffles you have the quiter the can will be.. In the picture above you will notice how some of the cores have only a few baffles, and my guess would be those don't suppress well.. The more baffles the marrier, of course there are other aspects to consider such as weight, caliber, volume, weapon type, etc.etc.. which will be utilized an some other stuff too but generally speaking the more of the gasses you can contain i.e. by use of more baffles the quieter it'll be.. Just a like how a car muffler wrks

If you use 17-4, for the tubing, you can thin the wall a bit more.
I would shoot for an 8" minimum length. Look at most comparable, commercial cans, in your design range.
Shorten up that blast chamber. No need for 2".
I'd use a good muzzle brake and space the first baffle 1/2" off it.
Look at a cut-away of a Saker, Harvester, Omega or Sig762. No giant blast chamber and a bunch of cone type baffle stacked closely.

I wouldn't expect a supersonic 300blk to be anywhere near hearing safe. Actually, no supersonic round is hearing safe.

I run a 6" 1.5" OD Can on my 16" 5.56 that is hearing safe with supersonic rounds.
A bunch of baffles stacked together is better for subsonic work does but not work that well for supersonic work.
My 6" can on my 5.56 has 6 baffles and spaced out as follows = baffle , baffle , .220" spacer , baffle , .320" spacer , baffle , .325" spacer , baffle , .350" spacer , baffle , 1.205" blast  spacer. With a YHM QD Flash hider and is totally hearing safe with full power rounds.  All freeze plugs are formed with JGS form tool and baffle holes are drilled .261"

Now my 300 blackout can is 8" long 1.5"  OD with 15 formed stainless freeze plugs drilled .375" , 1.255" blast spacer and a YHM QD Brake and is very quiet with subs not quiet with supers. It quiets down supers but is not hearing safe.

Your not going to get the best of both worlds you have to build the can for what you will be shooting. If I was shooting supers out of my 300 blackout I would build it similar to my 6" 5.56 can. It would still be quiet with subs but not as quiet as my current baffle stack.

If you want the best suppression for 30 cal a 1.625" OD can will be your best bet.
If you look at Ryans cans he built over on Form1 suppressor forums you will see his reflex cans work very well.

I am in the process and waiting on my form 1 to get approved and I'm building a reflex supersonic can for my 308 Win its a 1.625" OD 8" long and I will be using 60 degree baffles with .500 skirts  double clipped with around a 2" blast chamber.

Got a source for 17-4 tubing?

My lathe, some bar stock and a boring bar
Sorry, I don't know anywhere to get "by-the-foot" for a reasonable cost.


Not sure if this was a typo, but the majority of suppressors designed for low-pressure rounds exhibit similar features. Usually being larger volumes, of tubing and/or coaxial spacing, and a greater spacial distance between baffle faces.
All 4 suppressors I listed contain small blast chambers and baffles closely stacked. They are also top performers, for supersonic rounds.


As stated many times, OSHA lists "hearing safe" to be under 85db.
Please, show me a properly metered, supersonic round, which is anywhere near this number.
Because you can shoot w/o earpro does not make it hearing safe. Tolerable, maybe, but not hearing safe.

I came to the same conclusion after contacting a bunch of metal distributors. I'm not relishing the idea of taking a 8in x 1.5in bar of 17-4  and turning it into a tube.

It is my understanding that after 5-6 baffles you diminished returns (Please correct me if I am wrong). I feel that instead of taking up more internal volume by adding as many baffles as possible it may be best to stick with 5 or 6 cone baffles. Also is there much gain in a tapered bore like the M4-2000 uses? I makes sense to me that slightly larger bore in the blast chamber and first couple baffles will allow the gas to cycle back better and tighten up the bore in the end to slow it down. I could be way off in left field with this though.

 

Ok well then not hearing safe. Lol
Just my experience with the form 1's I have built. My 300 blackout can sucks with supersonic rounds and that's 15 baffles stacked in a 7.6" tube with a YHM QD Muzzle brake.
Its looking like less baffles and big blast chambers with these reflex can is were its at.
I will know how good it performs  when I get my form 1 approved and parts. The build Ryan has done are fantastic  I hope mine come out working that well.

That is for an 8hr period... OSHA's permissible exposure limit (PEL) is 90 dBA for all workers for an 8 hour day. The OSHA standard uses a 5 dBA exchange rate. This means that when the noise level is increased by 5 dBA, the amount of time a person can be exposed to a certain noise level to receive the same dose is cut in half.

ETA: If you chart it out the impulse noise of a gunshot could fall into the "hearing safe range" (depending on the impulse duration of a gunshot)
dBA......TIME
80......8
85......4
90......2
95......1
100......30
105......15
110......7.5
115......3.75
120......1.875
125......0.9375
130......0.46875
135......0.234375
140......0.1171875

A supersonic round, even suppressed, measures higher than OSHAs chart.
If you read the entire section, you'll find that any sound higher than the chart maximum, and having a duration under 1 sec (a gunshot), is considered a continuous sound.
Furthermore, both OSHA and NIOSH recommend ear plugs used along with muffs, for even a single gunshot.
Quite far from "hearing safe".

<1 sec would be an impulse sound, not continuous. Under OSHA impulse PEL's, anything over 140 dB would not be hearing safe (with or without hearing protection due to bone conduction).  The chart you are

looking at states that if you have a repeating noise (hammering, etc) at intervals of 1 sec or less than it would be considered continuous, not a noise impulse <1 sec = continuous. If you are slow firing with a

suppressor that attenuates noise < 140 dB than it would indeed be "hearing safe", if you are rapid firing faster than 1 round a second than you would require hearing protection according to OSHA.

Maybe we are looking at 2 different charts/sections.
I know which ruling you speak of and it is correct, for the jackhammers.
However, the chart in 1910.95(a) only goes to 135db.

The point you're missing is that these time/sound level charts factor in the operator/worker wearing hearing protection AND be given an annual hearing test, when exposed to or above the chart averages.
Add this to the fact that NIOSH and OSHA recommend BOTH foam plugs and ear muffs, to be worn for gunshots, means your 556 w/ ANY suppressor, and supersonic ammo, is NOT hearing safe.

Wear it or don't.
I just feel it is destructive and irresponsible to tell anyone that their firearm is "hearing safe", simply because you threaded on a suppressor.
Being a responsible gun owner doesn't just mean you don't muzzle sweep anyone.

I often have wondered about this where the trade off is between less volume and more baffles and the other way around. Would love to see some input on this before I start drilling cones.

Have a look at Sig's newer design (in the middle), and tell me if less baffles would be better. Their eggs are obviously in the "more" basket.
Also, notice there is no spacing change. 13-60* cones, spaced 3/8" apart, with all cones (except blast) being clipped and, at least some, ported (drain holes).
It's more about tuning and testing, something which is hard for a form 1 guy to accomplish.


The one on the left should be an Omega

^^^

This guy know what's up

Thanks! I guess I'll just cram as many baffles in as I can!

I understand where you are coming from, but you are equating that Impact noise and continuous noise have the exact same mode of damage to our ears, the fact is that we loose stereo cilia by fatigue through continuous noise exposure

( long periods of noise above 85 dB) or by pressure impulses above 140 dB. During my CAOCH cert. class I asked the audiologist what the cutoff was between safe for hearing vs damage when it comes to impulse,  I was answered that 140dB was the cutoff

and that we can reasonably be assured that anything under 140 dB impulse will not cause hearing damage. Yes NIOSH says that to attenuate noise damage from a gun shot to use duel hearing protection, but the moment we put a silencer on we change the

characteristics of the gun shot (both pressure, duration, and pitch) thus it is no longer the gun shot noise signature that NIOSH studied and no longer applicable to suppressed fire arms. To get back on point however, most form 1 cans and many factory rifle cans

are a average of what they say they attenuate, and the first shot is more than likely above 140 dB as well as the random shot in the group thereafter. thus hearing protection would still need to be used when shooting due to the potential for hearing damage,

Pistol cans and 22 cans I would have no problem calling them hearing safe as they are almost always under 140 dB, in my professional opinion as an industrial hygienist.

Someone said K baffles aren't good in rifle applications. Is that solely due to the strength problem or are they not as quiet? I talked to a small manufacturer on another forum that preferred the K baffle design for .223 rifle use (on long 24" barrels) over stepped cones or 60 degree cones, but admitted the K's won't hold up to shorter barrels or heavy loads.

The only reason I ask is because I had a thought on how to make a K baffle that will support heavy rifle loads, even 5.56 SBR use. I am not sure it's an original idea because it's so simple I can't believe it hasn't been thought of before.

Edit: Actually I found out a Russian suppressor is using the exact design I thought of already... nothing new under the sun apparently. The slightly altered shape of the K forms a much stronger support structure than a more flat top would.

So I'm waiting on my F1 to come back for my first homemade suppressor. I plan on using it for 308, 556, and maybe 7.62x39, 5.45x39 and eventually MAYBE 300BLK. So basically what I'm understanding from this thread, since I will be wanting to shoot mainly supersonic calibers, it would be better for me to use as many baffles as I can fit, with a blast chamber maybe 1/2" longer than the muzzle brake mount that I will be using, rather than a smaller amount of baffles with a spacer between each one? I was thinking about using titanium VSRs with spacers to create 7 baffles, basically. But now I'm thinking maybe just freeze plugs would be better? Am I completely misunderstanding all this? And would I not need spacers between? So it would be blast chamber then baffles against each other? Sorry for all the probably basic/stupid questions. Just want to understand before I waste money on the wrong stuff.