jesse james new can, 10db quieter than the best?

[Bendersquint]

Grounded went football/baby/reloading this afternoon lol

I am testing with the following:

Brüel & Kjær 4944-A mic, LAN-XI front end and i'm sampling @ 102.4kHz.
M855 ammo
1m perpendicular to the bore.


What i've found is the M42000 in my test rig is actually louder than the claimed numbers. For instance I measure unsuppressed at 173dB with a B-duration of something like 11ms. The m42k was ~148dB and mine is just over 140dB. Mind you this is only in my test configuration and comparing numbers from mrf specs to others can tend to be useless unless testing is always consistent. I don't know that the milspec test is even sampling fast enough to accurately measure peak dB.

My M42k Mod08 metered right at the 35 dB reduction.

[Grounded]

Throw up pics.

I can't at this time, Patent is in progress. I can tell you its development was .gov funded.

[Grounded]

Grounded went football/baby/reloading this afternoon lol

I am testing with the following:

Brüel & Kjær 4944-A mic, LAN-XI front end and i'm sampling @ 102.4kHz.
M855 ammo
1m perpendicular to the bore.


What i've found is the M42000 in my test rig is actually louder than the claimed numbers. For instance I measure unsuppressed at 173dB with a B-duration of something like 11ms. The m42k was ~148dB and mine is just over 140dB. Mind you this is only in my test configuration and comparing numbers from mrf specs to others can tend to be useless unless testing is always consistent. I don't know that the milspec test is even sampling fast enough to accurately measure peak dB.

My M42k Mod08 metered right at the 35 dB reduction.

but with which mic/front end?

[Grounded]

I don't pay attention to dB claims because it comes down to people running tighter bores than are prudent. In other words, the M4-2000 could be 6dB quieter than an M4-2000 if we just made the bore smaller. So who cares if someone else decides to run the risk to claim they are quieter? Not that genuine break thoughts never happen - they do, but I only believe them when tested with the same bore size.

My blast baffle is .260" and it grows from there. I think we all can agree that most of the designs out there do a good job of disrupting the flow except for the straight channel of the bore which is wide open. I get critical interference of the shockwave following the bullet as it uncorks from the barrel. Think air curtains as you enter a store.

[66427vette]

Throw up pics.

I can't at this time, Patent is in progress. I can tell you its development was .gov funded.

Will not show the outside of it ? Not passing the sniff test. Best of luck.

[Grounded]

Throw up pics.

I can't at this time, Patent is in progress. I can tell you its development was .gov funded.

Will not show the outside of it ? Not passing the sniff test. Best of luck.

.

Outside is one thing, I thought you wanted internals. I think I have an earlier prototype I can give you a shot of.

[66427vette]

I would like to see all of it but it's your choice.

[wacki]

I don't pay attention to dB claims because it comes down to people running tighter bores than are prudent. In other words, the M4-2000 could be 6dB quieter than an M4-2000 if we just made the bore smaller. So who cares if someone else decides to run the risk to claim they are quieter? Not that genuine break thoughts never happen - they do, but I only believe them when tested with the same bore size.

The jessie james can looks like it's a barrel extension. It don't get much tighter than that.

I'm not endorsing the JJ can. I'm just surprised heavily ported barrels aren't more common given the instant 6 dB improvement. Not even the integrals seem to go that route.

EDIT: I'm not a seasoned expert in this industry. I'm just asking questions and trying to learn.

[57fairlane]

Grounded went football/baby/reloading this afternoon lol

I am testing with the following:

Brüel & Kjær 4944-A mic, LAN-XI front end and i'm sampling @ 102.4kHz.
M855 ammo
1m perpendicular to the bore.


What i've found is the M42000 in my test rig is actually louder than the claimed numbers. For instance I measure unsuppressed at 173dB with a B-duration of something like 11ms. The m42k was ~148dB and mine is just over 140dB. Mind you this is only in my test configuration and comparing numbers from mrf specs to others can tend to be useless unless testing is always consistent. I don't know that the milspec test is even sampling fast enough to accurately measure peak dB.

Your setup is off.

I've got the same NI 4439/GRAS microphone setup as Silencerco and Major and my m42k metered several times in the 132-134 range. Also measuring unsuppressed in the 168-169 range

I agree your testing needs to be consistent but your numbers are way outside the norm.

[doubloon]

...
The jessie james can looks like it's a barrel extension. It don't get much tighter than that.
....

???
What does barrel extension have to do with bore size?

The SBX barrel extension has a "bore" >1" in diameter.

[Grounded]

Grounded went football/baby/reloading this afternoon lol

I am testing with the following:

Brüel & Kjær 4944-A mic, LAN-XI front end and i'm sampling @ 102.4kHz.
M855 ammo
1m perpendicular to the bore.


What i've found is the M42000 in my test rig is actually louder than the claimed numbers. For instance I measure unsuppressed at 173dB with a B-duration of something like 11ms. The m42k was ~148dB and mine is just over 140dB. Mind you this is only in my test configuration and comparing numbers from mrf specs to others can tend to be useless unless testing is always consistent. I don't know that the milspec test is even sampling fast enough to accurately measure peak dB.

Your setup is off.

I've got the same NI 4439/GRAS microphone setup as Silencerco and Major and my m42k metered several times in the 132-134 range. Also measuring unsuppressed in the 168-169 range

I agree your testing needs to be consistent but your numbers are way outside the norm.

Its always been calibrated properly prior to testing but I will absolutely double check them.

This was straight data from my test. Shots are not in order by round count but by Pressure level. This was 11 rounds m855 through a 14.5" upper with an M42000

Maximum(Pa) Maximum(dB) B-Duration
Sample 1 764.576 151.647813 0.018781
Sample 2 746.105 151.435399 0.018575
Sample 3 656.637 150.325907 0.018962
Sample 4 569.879 149.095053 0.019018
Sample 5 569.31 149.086376 0.015684
Sample 6 543.911 148.689957 0.018826
Sample 7 529.108 148.450287 0.01904
Sample 8 524.638 148.376595 0.018987
Sample 9 518.379 148.272348 0.018851
Sample 10 507.91 148.095135 0.005581
Sample 11 461.335 147.259728 0.0082

[laxguy59]

Whats with the bore of this can having that barrel like thing running all the way through it? does that actually provide any benefit?

[Grounded]

Whats with the bore of this can having that barrel like thing running all the way through it? does that actually provide any benefit?

10 extra HP if you open carry while on your chopper. lol.

[Mongo]

From the pictures it looks like its going to be heavy. Hell the number of screws alone weigh more than some cans. To quote Jesse, "what have I been doing for my whole career? Building intake manifolds and exhaust systems...I understand exploding gas.". I find this statement extremely funny in that every one of his bikes and cars he would always bragged on how loud they were. Well here are the pictures of the new design and it looks a lot like a muffles from a motorcycle on the inside and outside. I have my doubts about how well it will work but we will see. I'm guessing the housing is cast aluminum which in a center fire rifle round is not a good idea. I would thin the tube down the center would seemingly tend to keep the flow linear and not diverge into the baffles. I am guessing that the bloated center of the can generates a low pressure zone that will cause gas flow divergence but I would also think that removing the tube would increase this. Of course if Jesse has experience with Red Jacket suppressors only then this may be a radical improvement from his perspective.

[laxguy59]

Whats with the bore of this can having that barrel like thing running all the way through it? does that actually provide any benefit?

10 extra HP if you open carry while on your chopper. lol.

So are you with JJFU?

[JasonM]

...

On an unrelated note, nice to see you on here Mongo!

[Bendersquint]

Whats with the bore of this can having that barrel like thing running all the way through it? does that actually provide any benefit?

10 extra HP if you open carry while on your chopper. lol.

So are you with JJFU?

Gonna say not affiliated.

Grounded is an 07/02 behind enemy lines(guessing CA), JJFU is in Austin, Texas.

I do look forward to reading Grounded's patent which if it is pending he should share it with us.

Which office funded you to design the silencer? I know that it isn't classified so it can be shared.....what is the office code?

[wacki]

...
The jessie james can looks like it's a barrel extension. It don't get much tighter than that.
....

???
What does barrel extension have to do with bore size?

The SBX barrel extension has a "bore" >1" in diameter.

Rob silvers says tighter suppressor bore makes m4-2000 a lot quieter. 6dB.

Neoprene wipes make bore as tight as possible and quiet pistol cans down.

I can't help but think nothing would trap air better than a heavily ported barrel. Not even neoprene wipes. Barrels squeeze bullets and trap air behind. I would expect far greater dB reduction than the 6 dB rob silvers states. This would probably require integral suppression though. Too difficult to align two barrels.


EDIT: I'm not a seasoned expert in this industry. I'm just asking questions and trying to learn.

[JasonM]

...
The jessie james can looks like it's a barrel extension. It don't get much tighter than that.
....

???
What does barrel extension have to do with bore size?

The SBX barrel extension has a "bore" >1" in diameter.

Rob silvers says tighter suppressor bore makes m4-2000 a lot quieter. 6dB.

Neoprene wipes make bore as tight as possible and quiet pistol cans down.

I can't help but think nothing would trap air better than a heavily ported barrel. Not even neoprene wipes. Barrels squeeze bullets and trap air behind. I would expect far greater dB reduction than the 6 dB rob silvers states. This would probably require integral suppression though. Too difficult to align two barrels.

Wacki- really man, you have some half baked understanding of all of this stuff. (including your recent posts about terminal effects and ammo choice).

Wipes don't actually quiet all pistol cans down.

Ported barrels are not very good at "trapping air" as you say. They are actually pretty bad. Anything that guides the flow down the bore is bad for performance. The gas wants to expand, and having an open design with baffles, allows more of the gas flow to expand and be caught/diverted by the baffles. There is a reason all the best cans from the past couple decades do not use a ported barrel portion as their main 'suppressor'.

Ported barrels in suppressed weapons are used to drop pressure which slows bullets down, but has pretty little to do with the "silencing".

Do you not think, for example, HK would have built the MP5SD barrel/can your way if it worked better than the actual design?

[Grounded]

Gonna say not affiliated.

Grounded is an 07/02 behind enemy lines(guessing CA), JJFU is in Austin, Texas.

I do look forward to reading Grounded's patent which if it is pending he should share it with us.

Which office funded you to design the silencer? I know that it isn't classified so it can be shared.....what is the office code?

I'm definitely not affiliated with JJFU. Funding was provided through MARCORSYSCOM and I am currently entering the commercialization phase so its not classified work. I have a provisional patent for the utility and a patent app for the design that is further along. Bare with me here I know people make some crazy claims when it comes to suppressors. I am only relaying the info that i've acquired from my testing and I assure you I'm not making any of this up as hard as it may be to take at face value.

[Bendersquint]

Gonna say not affiliated.

Grounded is an 07/02 behind enemy lines(guessing CA), JJFU is in Austin, Texas.

I do look forward to reading Grounded's patent which if it is pending he should share it with us.

Which office funded you to design the silencer? I know that it isn't classified so it can be shared.....what is the office code?

I'm definitely not affiliated with JJFU. Funding was provided through MARCORSYSCOM and I am currently entering the commercialization phase so its not classified work. I have a provisional patent for the utility and a patent app for the design that is further along. Bare with me here I know people make some crazy claims when it comes to suppressors. I am only relaying the info that i've acquired from my testing and I assure you I'm not making any of this up as hard as it may be to take at face value.

Thank you for being up front.

I look forward to seeing what you came up with.

[Grounded]

I thought KAC had those locked down until I saw the stuff about the hot rod shop in Cali getting 1.6 million. Now all of those orders are going to be under super scrutiny.

[IAC533]

JJFU = Jessie James F'd Up ????

[SC-Texas]

Grounded,

I think your measuring equipment is a little off.

I look forward to seeing your can design and I hope its as quiet as your meter says it its.

[wacki]

Do you not think, for example, HK would have built the MP5SD barrel/can your way if it worked better than the actual design?

About once a week I see a scientific paper of a miraculous discovery found by accident. Many of these revolutions look obvious in retrospect. (E.g . Hoplon funnel) So yes, I fully expect oversights to be common.

E.g.

http://arstechnica.com/science/2013/08/ ... -accident/


I still don't understand why a bullet squeezing heavily ported barrel (60%+ steel removed) won't be more effective than baffles at trapping noise causing expanding air. Especially given Rob Silvers statement. Its tight, slows bullet down a bit allowing more time for the faster moving air to expand and could have just enough steel to guide the bullet between baffles. But ill save that debate for another time.


EDIT: I'm not a seasoned expert in this industry. I'm just asking questions and trying to learn.