step cut or "scoop"

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delta9mda
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step cut or "scoop"

Post by delta9mda » Wed Apr 27, 2016 9:15 pm

pros/ cons of step cutting (aac, griffin) or scoop cut (swr. sico, rugged, dead air)? all else equal its the same?

thanks bros
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Re: step cut or "scoop"

Post by curtistactical » Fri Apr 29, 2016 9:49 pm

I am still working on different calibers with this so I don't have info for different calibers yet but here is what I have tested and found so far. I started with an all cone 30cal suppressor with no clips and 8 cone baffles, next I put the radius scoop in, lastly I cut them .125" deep to center of the bore. I tested this using 308 200gr subs and 308 175gr supers. With both loads the .125" to cl cut was around 5db quieter than the radius cut and both were dramatically quieter than unclipped. My next tests will be with 45acp and more of a radius snorkel cone rather than a 60 degree cone.
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Re: step cut or "scoop"

Post by mikerla » Wed May 04, 2016 10:21 pm

curtistactical wrote:I am still working on different calibers with this so I don't have info for different calibers yet but here is what I have tested and found so far. I started with an all cone 30cal suppressor with no clips and 8 cone baffles, next I put the radius scoop in, lastly I cut them .125" deep to center of the bore. I tested this using 308 200gr subs and 308 175gr supers. With both loads the .125" to cl cut was around 5db quieter than the radius cut and both were dramatically quieter than unclipped. My next tests will be with 45acp and more of a radius snorkel cone rather than a 60 degree cone.
Joe
Can you share some pictures?

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Re: step cut or "scoop"

Post by mikerla » Wed May 04, 2016 10:23 pm

curtistactical wrote:I am still working on different calibers with this so I don't have info for different calibers yet but here is what I have tested and found so far. I started with an all cone 30cal suppressor with no clips and 8 cone baffles, next I put the radius scoop in, lastly I cut them .125" deep to center of the bore. I tested this using 308 200gr subs and 308 175gr supers. With both loads the .125" to cl cut was around 5db quieter than the radius cut and both were dramatically quieter than unclipped. My next tests will be with 45acp and more of a radius snorkel cone rather than a 60 degree cone.
Joe
Can you share some pictures?

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Re: step cut or "scoop"

Post by BinaryAndy » Thu May 05, 2016 11:28 am

curtistactical wrote:I am still working on different calibers with this so I don't have info for different calibers yet but here is what I have tested and found so far. I started with an all cone 30cal suppressor with no clips and 8 cone baffles, next I put the radius scoop in, lastly I cut them .125" deep to center of the bore. I tested this using 308 200gr subs and 308 175gr supers. With both loads the .125" to cl cut was around 5db quieter than the radius cut and both were dramatically quieter than unclipped. My next tests will be with 45acp and more of a radius snorkel cone rather than a 60 degree cone.
Joe
That is some great information, very generous of you to share. Thanks.
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Re: step cut or "scoop"

Post by daviscustom » Thu May 05, 2016 12:52 pm

That is a substantial difference.....could you tell us the size and depth of the scoop cut for a more informed comparison?.....Guessing it was much smaller in terms of how much it enlarged the bore size?

Have you tried comparing a clipped cone to a one that has been scoop cut big enough that the area of the bore increase was about equal to the bore increase of the clipped cone?
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Re: step cut or "scoop"

Post by curtistactical » Thu May 05, 2016 4:48 pm

I don't have any photos of the scoop cut but it was done using a .312" ball nose end mill and taken .16" deep. The photo below is what I ended up on being the quietest. In the next few weeks I will be playing with 45acp baffles doing the same thing, I will be sure to get some photos for sharing.
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Re: step cut or "scoop"

Post by T-Rex » Thu May 05, 2016 5:02 pm

Great info, Joe, thanks.
Have you tried moving the cutter away from the bore, with a clipped cut?
Or different depths of cuts?
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Re: step cut or "scoop"

Post by curtistactical » Thu May 05, 2016 6:24 pm

T-Rex wrote:Great info, Joe, thanks.
Have you tried moving the cutter away from the bore, with a clipped cut?
Or different depths of cuts?
I have tried going 1/4 of the bore across and it was pretty close to the scoop cut. I am expecting the 45 to be a different animal though, time will tell. I am sending my meter out for a new mic and calibration next week so I hope that don't take too long.
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Re: step cut or "scoop"

Post by daviscustom » Thu May 05, 2016 7:49 pm

Thank you for sharing that info.

Very interested to hear how the 45 comes out.....working on a .458 myself, but without a meter.....and on a form 1 can, it is a challenge to compare changes....pretty much have to look for big changes, and even that can be a challenge when having only scattered opportunities to work on it.
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Re: step cut or "scoop"

Post by Rich V » Thu May 05, 2016 8:47 pm

Great info Joe, thanks for sharing.

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Re: step cut or "scoop"

Post by S4area51 » Mon May 09, 2016 10:08 pm

Good info CT. Did you clip the blast? Also, were the baffles aligned during sound testing?

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Re: step cut or "scoop"

Post by curtistactical » Mon May 09, 2016 10:25 pm

S4area51 wrote:Good info CT. Did you clip the blast? Also, were the baffles aligned during sound testing?
I never clip the blast baffle no matter design, I have found 180 degree orientation on cones to work the best, that's how tests were done.
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Re: step cut or "scoop"

Post by 1rosta » Mon May 09, 2016 11:23 pm

Is there a slight inward cant on the cut or are my eyes off?

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Re: step cut or "scoop"

Post by curtistactical » Tue May 10, 2016 7:54 am

1rosta wrote:Is there a slight inward cant on the cut or are my eyes off?
Nope its just a straight cut on centerline.
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Re: step cut or "scoop"

Post by RogerH » Mon May 16, 2016 9:55 pm

Could you point me to more info on these cones? Thanks

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Re: step cut or "scoop"

Post by HotLead » Sun Jan 28, 2018 5:04 pm

Any chance y'all could re-post pictures? All I see are broken links!
This is great information, keep it coming.
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Re: step cut or "scoop"

Post by doubloon » Sun Jan 28, 2018 5:09 pm

HotLead wrote:Any chance y'all could re-post pictures? All I see are broken links!
This is great information, keep it coming.
try the photobucket hotlink fix

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