Endcap design question.

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policetruck
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Endcap design question.

Post by policetruck » Mon Jun 06, 2016 10:44 am

I've been searching but can't seem to find my answer. I remember reading something about building a cone into the Endcap as an easy way to get another baffle in and or to help with suppression. But when I look at opened/cutaways of modern top contenders suppressors, I only see flat endcaps usually with a bit of room between it and the last battle. Is it better for sound suppression to have that larger chamber with th a flat internal surface before the exit or to have a cone on the exiting face of the cap? Keep in mind I'm purely asking about sound suppression not maintaining a certain level of accuracy. I understand some designs are not purely for sound reduction.

crazyelece
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Re: Endcap design question.

Post by crazyelece » Mon Jun 06, 2016 2:04 pm

You will notice the weight more than the sound reduction, and there is no easy way of machining it other than solid wieght

I tried it on my last form1 build - no advantage that I found. It was for a bolt gun used on a bipod or a bag so the weight didn't bother me either.

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gunny50
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Re: Endcap design question.

Post by gunny50 » Mon Jun 06, 2016 3:19 pm

crazyelece wrote:You will notice the weight more than the sound reduction, and there is no easy way of machining it other than solid wieght

I tried it on my last form1 build - no advantage that I found. It was for a bolt gun used on a bipod or a bag so the weight didn't bother me either.
A lot of people machine their parts from barstock.
I did find that there is a difference, in rating - tone.

Making them flat like a lot do is cheaper to machine / stamp and takes less material and les time, so money in the bank.

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yondering
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Re: Endcap design question.

Post by yondering » Mon Jun 06, 2016 8:54 pm

Gunny, if you don't mind me picking your brain a little on that - did you try a straight 60deg cone in the endcap, or a radius/frustro cone, etc, or? Have you tried making the endcap a cone (i.e. not flat externally)? Seems like that might be bad for sound but I don't know.

cdhknives
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Re: Endcap design question.

Post by cdhknives » Mon Jun 06, 2016 9:01 pm

Why couldn't you build your final cone with zero skirt?

Why couldn't you build your endcap with a cone facing into the can? Does it really have to be flat on the exterior except from convention?

Same end result. No solid barstock endcap. Could be done on a manual lathe with no real extra skills over standard cones.
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gunny50
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Re: Endcap design question.

Post by gunny50 » Mon Jun 06, 2016 9:26 pm

cdhknives wrote:Why couldn't you build your final cone with zero skirt? Do not understand the skirt part, but might be that's because English is not my native language.

Why couldn't you build your endcap with a cone facing into the can? You can easily but takes more material - Time to produce than flat

Does it really have to be flat on the exterior except from convention? No, is does not have to be flat from the outside

Same end result. No solid barstock endcap. Could be done on a manual lathe with no real extra skills over standard cones.

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gunny50
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Re: Endcap design question.

Post by gunny50 » Mon Jun 06, 2016 9:33 pm

yondering wrote:Gunny, if you don't mind me picking your brain a little on that -
did you try a straight 60deg cone in the endcap, Yes we do on most of my silencers. My very first where flat like in 94 / 95 but even than we found that the end-cap can have features that will help in reducing - giving more pleasing tone - flash suppression.
or a radius/frustro cone, etc, or? Did some tests but like the straight cone better, also do have other contours / profiles on the inside.
Have you tried making the endcap a cone (i.e. not flat externally)? Yes we do on the MG cans, these are all Inconel 718 and 2" and for weight savings I did cut them cone inside, contra cone outside.
Seems like that might be bad for sound but I don't know. On the minimi we did not think it was making it a bad can ;-)

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cdrissel
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Re: Endcap design question.

Post by cdrissel » Mon Jun 06, 2016 10:10 pm

Like this ?

Image

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gunny50
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Re: Endcap design question.

Post by gunny50 » Tue Jun 07, 2016 4:26 am

cdrissel wrote:Like this ?
Yes
Without all the milling, that part was completely made on a mill, mine come from a CNC lathe.

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Re: Endcap design question.

Post by BinaryAndy » Tue Jun 07, 2016 6:34 am

gunny50 wrote:
cdrissel wrote:Like this ?
Yes
Without all the milling, that part was completely made on a mill, mine come from a CNC lathe.
I could make that part entirely on my CNC lathe. Probably in one operation. :twisted:
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cdrissel
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Re: Endcap design question.

Post by cdrissel » Tue Jun 07, 2016 9:55 am

Yes, do you have duel spindles and live tooling?

I only have access to CNC mills right now.

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Re: Endcap design question.

Post by c5_nc » Tue Jun 07, 2016 12:28 pm

In a threaded endcap (in reference to the solvent trap parts) the threading has depth to it (about .45" in the most common application), where as in a commercial can it is a welded tube and the cone can be placed closer to the exit end. In that case in the commercial can with the baffle closer to the end, it would make since for the cap to be flat, it is basically taking advantage of an otherwise wasted space.

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Bendersquint
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Re: Endcap design question.

Post by Bendersquint » Tue Jun 07, 2016 1:23 pm

cdrissel wrote:Like this ?

Image
We have done this on a 300BLK build, sounded GREAT! Not fancy as that though just straight off the lathe.

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yondering
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Re: Endcap design question.

Post by yondering » Tue Jun 07, 2016 9:06 pm

cdrissel wrote:Like this ?

Image
Nice, that looks good!

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