308 design critique

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NChobbymachining
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Re: 308 design critique

Post by NChobbymachining » Wed Apr 06, 2016 7:30 pm

I shortened the brake up a little bit. I left the hole as a circle because it will be easier for me to drill it than to mill it. I may make one with squared ports in the future though. I am not super worried about the brake performance without the can. I am hoping to shoot mostly suppressed on the 308 once the can is made and the 300 blk doesn't recoil much anyway. The new brake and end cap cut the weight by 3 oz (I was wrong before, the brake and end cap were 8 oz, now they are around 5) which gives me a total weight of 20.4 oz which is acceptable for me.

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Re: 308 design critique

Post by NChobbymachining » Wed Apr 06, 2016 8:39 pm

I had an idea to make sure the brake is still effective even when it is shortened. It was inspired by the blast shields that people use that thread onto breaks. I think as long as I drill the ports with the "Brake Enhancer™" already mounted, they should line up and should align every time. It will also mean I will need to match each "Brake Enhancer™" to the brake.

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fishman
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Re: 308 design critique

Post by fishman » Wed Apr 06, 2016 8:45 pm

that looks much better.
i like the idea of making the brake longer via an extension that threads on.
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mcrump
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Re: 308 design critique

Post by mcrump » Thu Apr 07, 2016 4:42 pm

I know this is a stupid question, but does baffles for big bore rifles not get some kind of "mouse" or "vent" hole
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Re: 308 design critique

Post by fishman » Thu Apr 07, 2016 5:09 pm

mcrump wrote:I know this is a stupid question, but does baffles for big bore rifles not get some kind of "mouse" or "vent" hole
they usually are clipped or ported, or sometimes both
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5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647

NChobbymachining
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Re: 308 design critique

Post by NChobbymachining » Thu Apr 07, 2016 8:06 pm

fishman wrote:
mcrump wrote:I know this is a stupid question, but does baffles for big bore rifles not get some kind of "mouse" or "vent" hole
they usually are clipped or ported, or sometimes both
How does the clipping help? Since this is going on a precision rifle, would it be best to leave the baffles concentric?

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fishman
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Re: 308 design critique

Post by fishman » Thu Apr 07, 2016 10:41 pm

NChobbymachining wrote:
fishman wrote:
mcrump wrote:I know this is a stupid question, but does baffles for big bore rifles not get some kind of "mouse" or "vent" hole
they usually are clipped or ported, or sometimes both
How does the clipping help? Since this is going on a precision rifle, would it be best to leave the baffles concentric?
its a little complicated how it works, im not expert on the topic, but long story short, asymmetry in the flow creates turbulence and that slows gas flow. clipping the cones should have very minimal effect on bullets flight as long as you leave the blast baffle alone, you could leave the first two alone if you wanted to err on the side of caution. you can always clip it later
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5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647

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mcrump
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Re: 308 design critique

Post by mcrump » Fri Apr 08, 2016 9:00 am

What's the difference between clipping and porting?
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Re: 308 design critique

Post by Capt. Link. » Fri Apr 08, 2016 9:48 am

fishman wrote: its a little complicated how it works, im not expert on the topic, but long story short, asymmetry in the flow creates turbulence and that slows gas flow. clipping the cones should have very minimal effect on bullets flight as long as you leave the blast baffle alone, you could leave the first two alone if you wanted to err on the side of caution. you can always clip it later
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Re: 308 design critique

Post by fishman » Fri Apr 08, 2016 10:11 am

mcrump wrote:What's the difference between clipping and porting?
Clipping is asymmetrically enlarging the bore hole in the cone. Porting, is drilling small holes in the cones.

Look up a cross section of sig Sauers 7.62 can. It's clipped and ported
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mcrump
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Re: 308 design critique

Post by mcrump » Fri Apr 08, 2016 12:31 pm

fishman wrote:
mcrump wrote:What's the difference between clipping and porting?
Clipping is asymmetrically enlarging the bore hole in the cone. Porting, is drilling small holes in the cones.

Look up a cross section of sig Sauers 7.62 can. It's clipped and ported
I did a search on Google and on this site. No luck on the sig can. Clipping is what I don't get.
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Re: 308 design critique

Post by T-Rex » Fri Apr 08, 2016 1:14 pm

mcrump wrote:
fishman wrote:
mcrump wrote:What's the difference between clipping and porting?
Clipping is asymmetrically enlarging the bore hole in the cone. Porting, is drilling small holes in the cones.

Look up a cross section of sig Sauers 7.62 can. It's clipped and ported
I did a search on Google and on this site. No luck on the sig can. Clipping is what I don't get.
Clipping
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Ported..Well, clipped and ported (the AAC M4-2K) Look towards the OD of the baffle.
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Re: 308 design critique

Post by Samson1044 » Sun Apr 10, 2016 10:54 am

mcrump wrote:
fishman wrote:
mcrump wrote:What's the difference between clipping and porting?
Clipping is asymmetrically enlarging the bore hole in the cone. Porting, is drilling small holes in the cones.

Look up a cross section of sig Sauers 7.62 can. It's clipped and ported
I did a search on Google and on this site. No luck on the sig can. Clipping is what I don't get.
the Sig can is in the middle , it does have a significant increase in volume as well do to added diamter
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