Looking for feedback on 308 can

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ed1380
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Looking for feedback on 308 can

Post by ed1380 »

I've had this design in my head for a while and have decided to model it. I went in with a basic understanding of how suppressors work, and this is what I have. Titanium is out of the question due to cost. I chose the "bullpup" design for a few reasons. Aesthetically I would like the can to start where the rail ends, and at the same time I think rails longer than 14" start looking ugly. Mechanically I don't feel comfortable with a couple pounds hanging off a single set of threads on the barrel. It can be used on any barrel up to 1 1/16". Just need the correct bushing machined. All 316SS.

I would appreciate any feedback on it. Especially baffle design.

Image



Before I was wanting to buy the cyclone
AAC cyclone is 16ci and 22.5oz
Currently this is 59ci and 61oz
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Enfield577
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Re: Looking for feedback on 308 can

Post by Enfield577 »

I would introduce a brake into the design (why not try a little harder to throw the gas back) and go for 60 deg cones rather than virtually flat washers, or at the least do something a little stronger with the blast baffle.

Cheers
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gunny50
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Re: Looking for feedback on 308 can

Post by gunny50 »

"ed1380"

1st, where are you located?

2nd.
Thats huge, 50s are 2 and 2,5" 8" long is okay for reflex design, as Enfield mentioned put an integral brake in your design.
61 oz 1,7 kg is like walking around with almost 2 rifles when mounted on the gun.


Check enfield, several others and my posts on over the barrel design with brakes, they do keep the gas back real good.

Gunny
ed1380
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Re: Looking for feedback on 308 can

Post by ed1380 »

Enfield577 wrote:I would introduce a brake into the design (why not try a little harder to throw the gas back) and go for 60 deg cones rather than virtually flat washers, or at the least do something a little stronger with the blast baffle.

Cheers
I just went through your history and saw the suppressor for the mk11. I must say great minds think alike :D This is going on the same gun, with a similarly designed suppressor.

What is your recommendation on endcap thickness? Mine are 1/8", but after seeing your suppressor it seems too thin. Also what do you think about smooth or stepped cones?

I am in GA, USA. Very lenient gun laws here
Last edited by ed1380 on Fri Aug 23, 2013 2:19 pm, edited 1 time in total.
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delta9mda
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Re: Looking for feedback on 308 can

Post by delta9mda »

Why why so thick front end cap? Make it .065 and be done with it.
NP
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Enfield577
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Re: Looking for feedback on 308 can

Post by Enfield577 »

ed1380 wrote:
Enfield577 wrote:I would introduce a brake into the design (why not try a little harder to throw the gas back) and go for 60 deg cones rather than virtually flat washers, or at the least do something a little stronger with the blast baffle.

Cheers
I just went through your history and saw the suppressor for the mk11. I must say great minds think alike :D This is going on the same gun, with a similarly designed suppressor.

What is your recommendation on endcap thickness? Mine are 1/8", but after seeing your suppressor it seems too thin. Also what do you think about smooth or stepped cones?

I am in GA, USA. Very lenient gun laws here
Hi
I would do like Delta says and make the cap thinner this time, I think 1/8" would be great but you could go thinner but do not have the sharp internal corners, put nice big rads there and maybe even a little cone in the centre, one last gas trap.

Definitely go with smooth cones, that was the first large can I made and it just worked so well, so why risk a different design.

I heard from the lady that I made the can for only last weekend and she is winning competitions out to 90 yards with it

Cheers
Of all the things I've lost it's my mind I miss the most
ed1380
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Re: Looking for feedback on 308 can

Post by ed1380 »

I thinned the front cap down to .075, but now I'm considering making the main tube and front cap aluminum. I can double the thickness and still save half a pound

I designed stepped baffles, but that'll be a pain to machine, so I might just go with smooth.

Image
Historian
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Re: Looking for feedback on 308 can

Post by Historian »

ed1380 wrote:I thinned the front cap down to .075, but now I'm considering making the main tube and front cap aluminum. I can double the thickness and still save half a pound

I designed stepped baffles, but that'll be a pain to machine, so I might just go with smooth.

Image
Actually the 'layered bathroom plunger' stepped baffles look quite intriguing
from a few perspectives.

I know that long ago I saw such a shape in some application but the particulars elude me.
Like trying to remember a name from long ago.
A chambered Nautilus.

Perhaps the good Captain, Mr. B., or the creative Enfield have
seen such layered configurations implemented in some mechanism or machinery somewhere.

As for fabricating them I sense that shape could be stamped/spun from a disk easier than
machining. Or even laser printed with the new technologies.

Is there a program that could simulate gas breakdowns/turbulences?
Mental 'Kentucky Windage' says that more thought be applied to this baffle design.*

Well done, Ed1380

Idle minds are indeed the Devil's workshop. :)


* If indeed this is novel shaped baffle perhaps its design should be registered.
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Dr.K
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Re: Looking for feedback on 308 can

Post by Dr.K »

It looks gigantic....and heavy!
Kyle O.
ed1380
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Re: Looking for feedback on 308 can

Post by ed1380 »

@ Enfield577 - How much did that can end up weighing? The forums aren't letting me search through your threads, so I can't find it.



Current iteration is AL outside and SS inside. It's down to 3lb, but I don't know if 1/8" aluminum is up the task

Image


more changes. 2.8lbs. front cap and baffle welded in. mostly stainless, but half the displacement.

Image

baffle stack is welded to the strips and assembled as one piece.

Image
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delta9mda
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Re: Looking for feedback on 308 can

Post by delta9mda »

"baffle stack is welded to the strips and assembled as one piece", lord why
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Enfield577
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Re: Looking for feedback on 308 can

Post by Enfield577 »

delta9mda wrote:"baffle stack is welded to the strips and assembled as one piece", lord why
Instead of spacers I guess, kind of interesting though complex to make and likely no better than spacers ???
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gunny50
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Re: Looking for feedback on 308 can

Post by gunny50 »

Enfield577 wrote:
delta9mda wrote:"baffle stack is welded to the strips and assembled as one piece", lord why
Instead of spacers I guess, kind of interesting though complex to make and likely no better than spacers ???
Far more complex.
I would say worse than spacers as spaces can also be calculated as wall, when welded of course.
Far more complex to machine.

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ed1380
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Re: Looking for feedback on 308 can

Post by ed1380 »

It saves 3oz over spacers. I'm trying to cut every bit of weight. The baffles are going to be cnc milled, and it'll only need to be welded once. It saves weight and makes assembly/cleaning easier. Why not.


Speaking of baffles. I'm not happy with this design. I don't thing they'll provide enough turbulence. Stepped 60* cones are looking like a viable option
Historian
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Re: Looking for feedback on 308 can

Post by Historian »

ed1380 wrote:It saves 3oz over spacers. I'm trying to cut every bit of weight. The baffles are going to be cnc milled, and it'll only need to be welded once. It saves weight and makes assembly/cleaning easier. Why not.


Speaking of baffles. I'm not happy with this design. I don't thing they'll provide enough turbulence. Stepped 60* cones are looking like a viable option
From 'for what it is worth department', extrapolating from long ago acquaintance
with fluid logic/turbulence study your 'drain plunger' baffle design is intriguing.
From a WAG analysis it seems to have possibilities. As a variant on the French canard
might express: "one should not necessarily toss her out of bed before trying". :)

It is a shame that a prototype cannot be made to test the actual DB ratings. I wonder if when
the K-baffle design was first patented if its 'complexity' was at first sight
seemed no better than stacked disks.

Again, a raised pint on you innovative thinking.

Best.
ed1380
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Re: Looking for feedback on 308 can

Post by ed1380 »

Historian wrote:
ed1380 wrote:It saves 3oz over spacers. I'm trying to cut every bit of weight. The baffles are going to be cnc milled, and it'll only need to be welded once. It saves weight and makes assembly/cleaning easier. Why not.


Speaking of baffles. I'm not happy with this design. I don't thing they'll provide enough turbulence. Stepped 60* cones are looking like a viable option
From 'for what it is worth department', extrapolating from long ago acquaintance
with fluid logic/turbulence study your 'drain plunger' baffle design is intriguing.
From a WAG analysis it seems to have possibilities. As a variant on the French canard
might express: "one should not necessarily toss her out of bed before trying". :)

It is a shame that a prototype cannot be made to test the actual DB ratings. I wonder if when
the K-baffle design was first patented if its 'complexity' was at first sight
seemed no better than stacked disks.

Again, a raised pint on you innovative thinking.

Best.
Thank you for the encouragement. I finally have access to a descent CFD, so I'll be looking more into it.

EDIT: Took a while to get the hang of it.


I'm very confused right now. I put a few different designs through the cfd and it looks like plain washers are the best. That can't be right.

Input: 3000ft/s at 50k psi and 500*
Output: atmospheric conditions

Only a strip was simulated because there's only a certain number of particles it can keep track of. Otherwise it looks like this. (useless)
Image


Definitely have no idea what's happening.

Picture is too big to hotlink
http://i.imgur.com/GfsgCgi.jpg

tried something else. Simulated half and mirrored it. There is definitely something wrong. The gasses are not expanding to fill the voids.
http://i.imgur.com/qO09EkP.jpg
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