Anyone tried this or a close variation?

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mosigdude
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Anyone tried this or a close variation?

Post by mosigdude »

Sorry that I lack the 3d rendering skills but hopefully this will be clear. Only diagrammed is the baffle/spacer portion of the stack, tubing will be using the standard threaded ends. This will be for a 1.375" suppressor, probably ending around 8-9 inches. It will be used exclusively on semi-auto 9mm /semi-auto 300BLK and bolt-action 308. I'm planning on making adaptors for all the hosts to bring them up to standard 5/8x24 so the can will be a thread-on mount.

Baffles will be oriented in the manner shown, the "face baffle" will have the through-hole on the top and the secondary baffle will have the face cut on the bottom of the front of the cone, this will continue throughout the suppressor. I can always step the cones to work the blast a little better if that seems to be a good trade for the added weight.

I'm interested in feedback from anyone using such a configuration, obviously anything is subject to being amended but I'd like to have the design squared away in the next few weeks, form 1 should arrive anytime.

Does either design appear workable? Which appears as if it will work best, top or bottom version?

How thick does the blast baffle set need to be if using 316 stainless? What about the baffles following?

As always, any input is appreciated

-T

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SRM
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Re: Anyone tried this or a close variation?

Post by SRM »

I like the second one. As far as the blast baffle, if you can hit it with a good sized hammer and it bends, make it thicker.
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Re: Anyone tried this or a close variation?

Post by SRM »

reverse the baffles and look at it.
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daviscustom
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Re: Anyone tried this or a close variation?

Post by daviscustom »

I like your idea....the second version the best. Looks like a lot of wide open space between the pairs though, I would wonder about having a shorter spacer between the pairs and gain room for more baffles.

What about a short tubular section on the top of the shallow cones to create a more enclosed expansion chamber in that open area?
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mosigdude
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Re: Anyone tried this or a close variation?

Post by mosigdude »

Ok, here's a slight design change that lets me squish more sets of baffles in, some of the space between pairs removed, all cone angles adjusted to 60 degrees. Better or worse?

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daviscustom
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Re: Anyone tried this or a close variation?

Post by daviscustom »

:D Me likes it. That creates a nice chamber between the two cones....I still think if you extend a short tube out of the top of the short cone you would create another chamber between the short cone and the tall one before it. Maybe just extending the short cone all the way out to the bore would work.

I hope someone else will chime in if I'm steering you wrong, but I think you are on to something interesting..... since you are intending it for lower pressure stuff only. I'm only addressing the basic design.....not sure how valuable the cuts are, but hopefully someone else will comment on that as well.
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mosigdude
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Re: Anyone tried this or a close variation?

Post by mosigdude »

My original thought on the holes and cuts in the baffles was to peel some of the gas flow from the main stream and to redirect it to cause more turbulance. I'm not sure how effective that will be but that was at least the thought. If I had a way to 3d model it and run it through some sort of flow software it would be interesting to see, although I'm not sure how accurate that is in regards to actual performance based on what others have commented previously.

Anyway, I think I know what you meant by adding the tubular section to the leading baffle... updated again:

Image


...and again to extend the leading baffle to bore diameter:

Image

These are both starting to get a lot of metal in them so I'm sure weight is coming up but I'm not intending this for a pistol so it shouldn't be a huge factor... I may have to spring for a titanium tube at least.

Better or backwards?
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daviscustom
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Re: Anyone tried this or a close variation?

Post by daviscustom »

My thought was to go the other direction with the tube, close to the bore so it bottle-necks the chamber on the other side of the shallow cone. Your way is interesting, but not what I was thinking.
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mosigdude
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Re: Anyone tried this or a close variation?

Post by mosigdude »

Ok, I think I got ya figured out. I think if I go that route (or maybe any of the other variations too) it might be better to make my cut on the outside of the full cone instead of the leading edge, just to give the gas/pressure a little further to travel back to the primary bore.

Getting closer?

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daviscustom
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Re: Anyone tried this or a close variation?

Post by daviscustom »

Not certain what to recommend about the cuts but that is what I was thinking about as far as changing the shallow cone.

I would be curious also to see the shallow cone extended all the way out to the bore (with the short tube) for comparison....kind of like your first two designs you posted. That would increase the capacity of that new chamber a little.....not sure if it would be more valuable to have that chamber larger or to have the current expansion room around the bore into the second chamber. (I know that seems clearly stated to me, but if it is clear as mud to you...let me know and I'll try again)

This looks pretty darn good to me but there are folks here with a lot more practical experience then me ...... :roll: :roll: :roll: :roll: I keep hoping someone else will put in their $0.02.
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mosigdude
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Re: Anyone tried this or a close variation?

Post by mosigdude »

I guess I could extend the "tube" portion of the short baffle out all the way to the bore and leave the OD of the same section the same. It would obviously be heavier and much more beefy than needed but after assembly, I could give it a few shots. If it sounds good I could shave off the OD and bring it back to a reasonable thickness. If it sounds bad I could open up the ID of the short baffle bore back to the thickness in the diagram while leaving the long-cone baffle diameter untouched. This should let the long cone carry a little more of the pressure/blast. The absolute worst-case scenario is I end up with a spaced-cone stack with a little extra deflection built in.

That seems like a pretty easy fix. I'm very interested in input on the ports since I can't un-mill them once I have them in.

Still looking for thoughts on baffle thickness other than the hammer method... which I appreciated but I'd feel really bad bashing supressor parts, haha. Maybe a starting point for the heaviest caliber which would be .308. (bore will be .415 to accomodate 9mm, btw) Still thinking 316 Stainless throughout.
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daviscustom
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Re: Anyone tried this or a close variation?

Post by daviscustom »

It sounds like we are both on the same page.

Another option would be to alternate the two styles of shallow baffle every other pair....maybe get the best of both worlds.
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Re: Anyone tried this or a close variation?

Post by mosigdude »

mosigdude wrote:
Image
One of my buds (the guy who got me started in NFA) has an un-made, approved, 22 cal form 1. He is scaling this down and giving it a go... first with only the long and short baffles with no scoops or cuts... this one is getting a real-world try, more (as I find out) to follow...
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daviscustom
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Re: Anyone tried this or a close variation?

Post by daviscustom »

I think this should work great in 22lr.....similar idea as the original silencerco sparrow, just conical instead of a monocore....1 1/8" od would give you lots of volume.
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mosigdude
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Re: Anyone tried this or a close variation?

Post by mosigdude »

daviscustom wrote:I think this should work great in 22lr.....similar idea as the original silencerco sparrow, just conical instead of a monocore....1 1/8" od would give you lots of volume.
He messaged me that it's done minus engraving but he's still at work and hasn't run it on the muzzle yet, I'm anxiously awaiting the results. He did it as a 1" and said it's a fraction under 6" long.
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daviscustom
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Re: Anyone tried this or a close variation?

Post by daviscustom »

Very cool, hope to hear a report soon.....and see video and pics before dark :wink:
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Re: Anyone tried this or a close variation?

Post by mosigdude »

daviscustom wrote:Very cool, hope to hear a report soon.....and see video and pics before dark :wink:
Just heard back, his word was "disappointing". I heard a few rounds through the phone which is difficult to judge but it does sound loud. He did not make any of the cuts in the cones yet so he's going to start with a "scoop" on the face of each cone tomorrow and trial it again. He said he left enough meat on the face that he could step them slightly if needed too. I'll keep you posted as I hear and I'll try to get some pics and a video, good or bad, shortly.

edited: This was on a Browning Buckmark btw
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daviscustom
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Re: Anyone tried this or a close variation?

Post by daviscustom »

That sucks....did he try it indoors by chance.....they sound louder inside. Any idea the length of barrel and if he was using subsonic ammo?
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Re: Anyone tried this or a close variation?

Post by mosigdude »

daviscustom wrote:That sucks....did he try it indoors by chance.....they sound louder inside. Any idea the length of barrel and if he was using subsonic ammo?
He was in his driveway when I heard it on the phone. I think it's a 5 or 5-1/2" factory barrel that he threaded. He was using the standard velocity CCI ammunition. I might be thinking of a different pistol but I remember it was somewhat "clacky" with a 9mm suppressor that was otherwise fairly quiet on other guns we tried it on. I'm going to take my Walther P22 and Ruger 10/22 over sometime this weekend and give it a go with those as well. I've heard a SWR Spectre on both of these guns so I might be able to make a little bit of a comparison from memory.
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daviscustom
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Re: Anyone tried this or a close variation?

Post by daviscustom »

I think I would try a scoop in the face of the tall cones...like your first drawings but more like a scoop on a k, not so flat faced.....and a mouse hole in the flat of the shallow cone. Try to push the gasses to the side into the next cavity and then it meets back pressure from the next one .......maybe slow things down some.

Did he leave a cavity for a blast chamber before the baffles started?
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Re: Anyone tried this or a close variation?

Post by mosigdude »

The suppressor is very quiet now with scoops added to the face and cuts made in the rear of each cone. Spacers are even length again and only 3/8" each. I haven't seen the internals yet but below should be a pretty close diagram according to a napkin sketch. I believe a lot of the noise I was hearing on the phone was from the "clack" of the pistol and in person it is very easy to discern from the action noise from the report of the gunshot noise. I'll post some pics and a video using some quieter hosts whenever we can get our schedules together.

Can't wait to try this on my centerfire can when paperwork arrives!!

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daviscustom
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Re: Anyone tried this or a close variation?

Post by daviscustom »

If that is what he made, I would think it would be better to make all the baffles like the one on the left so that each chamber is bottle necked instead of alternating.

The thing I liked about your design was that both baffles created an expansion area that was slightly restricted back to the bore.....and they were each a little different from the other so that should create different turbulence in the bore. His design would do that as well since it is alternating two different baffles, but I would tend to wonder if it would be quieter if he hadn't changed your design.
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mosigdude
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Re: Anyone tried this or a close variation?

Post by mosigdude »

You make a good point, I'll try all "left design" baffles on my scaled-up version and probably lightly step the cone portion on each just for a little extra turbulance. I'll add a little weight in doing so but this still won't be the heaviest can out there. Think I can get by with a .060" thick 316 SS spacer in the blast chamber and .040" in the rest?. I'm not counting on the spacers to add strength to the outer tube but they do need to keep the baffles spaced.

Edit: Maybe I'll make the blast chamber spacer of a coaxial design to make sure I don't have first round pop, thoughts?
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daviscustom
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Re: Anyone tried this or a close variation?

Post by daviscustom »

I'm not an engineer, but if you are comfortable with the can thickness, it would seem to me the spacer thickness wouldn't matter much....except for the inner chamber if you are doing a coaxial blast chamber.....for that I would guess you need some beef.

I'm also curious which variation the others will suggest for the best baffle design for the scaled up higher pressure version.......an awful lot of Bender's baffle pics are variations on a cone.... so I would think you are on the right track.
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mosigdude
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Re: Anyone tried this or a close variation?

Post by mosigdude »

I still didn't get a chance for pics or video but hopefully that will materialize this weekend. I'm anxious to see the guts, he's describing a minor change in the design that he made but I don't exactly know what he means. Regardless, I may ammend my original plans for my omega-based 22 LR can to a variation of this design after hearing his.
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