First form 1 build, critique my plans please

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bna5017
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Re: First form 1 build, critique my plans please

Post by bna5017 »

whiterussian1974 wrote: Sat Jan 11, 2020 5:31 pm
bna5017 wrote: Tue Dec 24, 2019 7:56 pm
T-Rex wrote: Tue Dec 24, 2019 5:43 pm What is the distance from muzzle brake to first baffle tip?
The distance from the end of the brake to the first baffle tip is 3/8". Too close? Too far?
I didn't see an answer to this, so I'd add my $.02 and say that I'd have the 1st baffle nearly kiss the brake. This would create a semi-enclosed blast chamber and also limit throat erosion on your blast baffle. Especially if the opening is just under the OD of your brake.

Also, why is your final baffle so far from your endcap? That is your lowest pressure Region. So you should have the MOST spacing there, not have it encroach upon the neighboring baffle.

You could also machine a cone on you endcap for the exit. Just a small .25" or so. I've seen many Builders include that.It helps with pressure retention, and also "smooths" the escaping gasses to increase Duration and thereby lessen Amplitude of the Atmospheric Disruption at Discharge.

Hope this helps. :D
Thanks for the input! I will either move the first baffle or extend the brake.

As far as the last baffle to end cap spacing, that was an attempt to have a substantial amount of thread engagement on the end cap and keep the baffles all the same. I'm reconsidering the end cap design and will probably make some changes there.

Everything I have read seems to indicate that the baffle spacing should decrease towards the end of the suppressor, correct me if I am wrong but it sounds like you're saying the distance between them should be greater towards the end?
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whiterussian1974
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Re: First form 1 build, critique my plans please

Post by whiterussian1974 »

Correct. The baffles are closest together in the high pressure region near the muzzle. They are furthest separated near the far end of the suppressor.
The lower the pressure, the less benefit. Also, high pressure directs the gasses off of boreline and into tight spaces. Low pressure needs more space in order for the gasses to depart the boreline.
OF course, I may be misremembering. Search other builds, and let them guide your design.
I haven't been on this site for 2 years, so I'm doing my best to recall everything. :D
I seem to recall that someone said it your way. That the velocity of exhaust gasses meant that spacing needed to be more at 1st, and then tighten up near the exit. So please don't depend upon me. Do whatever the other Threads have said works best. 8)

---ETA: The good news is, since you are using spacers, you can rearrange them and go with whatever works best for you. :mrgreen:

Another option: have you considered using a 45* cone or K-baffle for your final baffle? The pressure is so low by that point, maybe some others could chime in with their opinions?
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fishman
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Re: First form 1 build, critique my plans please

Post by fishman »

I haven't been on this site for 2 years, so I'm doing my best to recall everything.
why'd you bother coming back to this dump of a website lol
300 blackout form 1: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=137293

5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647
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whiterussian1974
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Re: First form 1 build, critique my plans please

Post by whiterussian1974 »

Good to see you again, Fisherman. :mrgreen:
The Darkest Corners of Hell are reserved for those who remain Neutral!-Dante
The Death of One is a Tragedy, a million only a statistic.-Stalin
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whiterussian1974
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Re: First form 1 build, critique my plans please

Post by whiterussian1974 »

Here a photo from another site showing the "retention cone" on the far endcap. Make it larger and slant drill holes to siphon gas from the exit tube, and it sounds quieter, smoother, more pleasant because of decreased atmospheric upset.

Image
The Darkest Corners of Hell are reserved for those who remain Neutral!-Dante
The Death of One is a Tragedy, a million only a statistic.-Stalin
silencertalk.com/forum/viewtopic.php?f=10&t=135314
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