45 Cal Suppressor Design Review

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ECCO Machine
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Re: 45 Cal Suppressor Design Review

Post by ECCO Machine » Wed Jan 09, 2019 1:18 pm

T-Rex wrote:My model has the skirt Thk @ .040 and I think the ledge length is half the Thk. I can't say I've ever gone much large than this. Unless your doing a feature like the CTA, I couldn't see a need for it. Any particular reason your serviceable cans are designed as such? Do you drop baffles into the tube or stack them and slide the tube over?
My serviceable cans have no ledge. Tube serves to align radially, and cone baffle clip alignment is done with a polymer rod that has a piece of keystock inset. The baffles are stacked on it then inserted, rod removed from the rear of the can. This is necessary to keep all 14 clips aligned with the modular design; the module itself has an integral baffle at the rear plus 4 more within.

My K baffles have a single 1/2" wide, .035" tall section at the rear face that mates with a cut at the front edge of the cone behind it (pic on pg. 1). Those are stacked face down and then the tube slid over.
T-Rex wrote: The biggest difference is the internal profile. The skirt flows into the cone w/ a simple tool nose radius. No need for that exaggerated step in the OP's design.
That's true. He might do well to make that a convex radius or bevel instead.
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Colo32
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Re: 45 Cal Suppressor Design Review

Post by Colo32 » Wed Jan 09, 2019 2:18 pm

Hopefully I am getting closer on this:
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Re: 45 Cal Suppressor Design Review

Post by Colo32 » Wed Jan 09, 2019 2:25 pm

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Re: 45 Cal Suppressor Design Review

Post by ECCO Machine » Wed Jan 09, 2019 5:59 pm

Colo32 wrote:Hopefully I am getting closer on this:
I think about all that's left is incorporating whatever feature you want for baffle alignment.

As I mentioned, I use a keyed rod on my Phoenix, but you don't have a clipped blast baffle. It could still be made to work, but the tool would have to allow the rod to be driven out separate from the key, and you'd need to sort out freeing the key from the clips. With CNC, it wouldn't be difficult to do a system like Thunderbeast uses on the Takedown .22:

https://goo.gl/images/v2Jqdp

It'll need something, they'll twist out of alignment when tightening the front cap.
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Re: 45 Cal Suppressor Design Review

Post by Colo32 » Wed Jan 09, 2019 6:03 pm

I need to choose between the staggered helix or the alternating helix design. The alternating design seems to me like it will have the most turbulence and resistance to flow. Considering the low pressure cartridge we are dealing with, which one SEEMS like it will be better? In my mind, the staggered helix has less resistance and could pack more gas in, in a shorter amount of time, before having to reverse direction and get out of Dodge. When you look an the end of the stack, you can clearly see a channel going straight to the front cap.
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This channel isn't present on the alternating design.

Is it going to be more benificial to pack more gas in quickly, or let it bounce around on the alternating helix design?

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Re: 45 Cal Suppressor Design Review

Post by Colo32 » Wed Jan 09, 2019 6:30 pm

ECCO Machine wrote:I think about all that's left is incorporating whatever feature you want for baffle alignment.
I have that on my to-do list while i'm waiting on my Form 1

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Re: 45 Cal Suppressor Design Review

Post by ECCO Machine » Wed Jan 09, 2019 7:04 pm

Colo32 wrote:
Is it going to be more benificial to pack more gas in quickly, or let it bounce around on the alternating helix design?
I really don't know. I think both are going to inhibit gasses entering the chamber a fair amount. Even the one with channels is gonna generate cross flow at each helix fin. I'll leave that one between you and T-Rex. I still favor only putting vanes on the first 3 baffles.
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Re: 45 Cal Suppressor Design Review

Post by T-Rex » Wed Jan 09, 2019 8:34 pm

Colo32 wrote:When you look an the end of the stack, you can clearly see a channel going straight to the front cap.
A couple things on this:

-An expanding gas isn't like a jet of liquid. The gas, while moving into the coaxial volume, will be doing so in all directions. It won't simply move straight down the channel, turn around, and head back out. It's expansion will cause collision with the vanes and the other gas streams. This expansion, along with its heat transferred to the vane material, will greatly reduce it's pressure/velocity. This is exactly what you want in a suppressor.


-You could index the blast baffle so its vanes obscure these "channels". You could, also, make the number of vanes, between the two, different. Say, 12 vanes on the blast baffle and 8 on the subsequent.

-You could, and this would be a change I'd consider, increase the helix angle of the vanes. Couple this with a slight increase in the number of vanes and you'll have even more disruption of the flow in this area. CAD can easily compute any difference in weight. However, as ECCO has been stressing, SS and Ti baffles can be quite thin for this design. Also, since your using cnc, your effort is minimal.
ECCO Machine wrote:I think about all that's left is incorporating whatever feature you want for baffle alignment.
I'll recommend the CTA design, again. It will be an easy feature to create with cnc. The baffles simply click together and hold tightly. Alignment is obtained and held.
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Re: 45 Cal Suppressor Design Review

Post by Colo32 » Fri Jan 11, 2019 2:19 pm

While I'm fiddling with various vane configurations, I would consider making the skirts separate from the face so I can try different combinations. Before I consider this option, I need some feedback on the porting options and their respective requirements. The asymmetrical that I have been showing needs to be aligned like I have it, Correct? What are the consequences if they're not?
What about symmetrical ports. I'm guessing orientation is irrelevant? Pros & cons for going this way?
I'm thinking about making a threaded ring to retain the baffles on the exit end so I can make a tool to lightly clamp the baffles in position once in the tube. This will allow easy removal of the tool if it has to incorporate a rib for port alignment. I would then have a endcap that screws on after that.

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Re: 45 Cal Suppressor Design Review

Post by daviscustom » Fri Jan 11, 2019 2:47 pm

A threaded ring would also protect the front cap from having the baffle stack hammering against it. Depending on how deep you thread back into the tube it would give you flexibility on the baffle/ spacer arrangement without needing to thread the whole tube.
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Re: 45 Cal Suppressor Design Review

Post by T-Rex » Fri Jan 11, 2019 3:03 pm

It's in my opinion that you're over-thinking/complicating this. Pistol designs rarely vary their baffle spacing. You could make a series of varying length vane segments, but it's only going to make it that much more difficult to keep aligned. As I've mentioned several times, look into the CTA feature and implement it. The baffles easily snap together/apart, and require no further fiddling w/ or tools to maintain alignment.

While I'm not 100% on the design of the CTA, it's, roughly, a tolerance fit between the skirt of one baffle and the face/ring of the next. The skirt will have a slight inside chamfer, to facilitate alignment and begin the engagement onto the subsequent baffle.
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Re: 45 Cal Suppressor Design Review

Post by Colo32 » Fri Jan 11, 2019 6:40 pm

I was only thinking about being able to rotate the baffles in different ways to try different fin alignments with what I already have designed, not mess with any spacing. That's the reason for the questions about the clipping style and orientation requirements.

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Re: 45 Cal Suppressor Design Review

Post by ECCO Machine » Fri Jan 11, 2019 7:56 pm

Colo32 wrote:I was only thinking about being able to rotate the baffles in different ways to try different fin alignments with what I already have designed, not mess with any spacing. That's the reason for the questions about the clipping style and orientation requirements.
So, radiused asymmetric clips do seem to be the quietest variety, but yes, they do need to be aligned to give optimal performance and minimal POI shift. Symmetric clipping is less likely to affect POI and less affected by orientation, but may not produce quite as much SPL reduction. That said, one of my compact rifle cans produced very impressive results with symmetrically clipped baffles (aligned). But I also never produced that model with asymmetric clips, so take that for what it's worth.

All of my rimfire cans have a symmetrically clipped 50° blast baffle and asymetric half-moon clips on the remainder of the 60° cones. Suppression and accuracy are unaffected by alignment.

I also recently tried a triple clipped design for 9mm cans that would be indifferent to orientation, but it didn't give as much suppression as K baffles. It's also a complex shape that's a pain to make, so I was honestly kind of relieved the Ks worked better!
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Re: 45 Cal Suppressor Design Review

Post by T-Rex » Fri Jan 11, 2019 8:00 pm

My apologies, the different configurations threw me. Separate baffles and spacers is always doable, if you'd like to experiment. This would be a reason I mentioned the addition of an end wipe. In my last 22lr design, I incorporated a variety of options, for the sake of experimenting.

There are a couple successful designs using symmetrical clips. I don't think your radial design would benefit from this, not w/o some revisions. Even then, there's no guarantee it will be better, w/o experimenting (which is off limits to a single F1 can). Aligned, asymmetric clips have proven successful in radial baffle designs.

I have to say that I don't think you'll be disappointed in the least at what has been hashed out. Your design goes a bit beyond what is commercially common in today's market. Your baffle profile is a proven success and there are plenty of them inside the can. In terms of volume and gas management, I feel you've gone above and beyond what most are likely to see.

Are you close to knowing a final weight?


ETA: ECCO covered a couple items....
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Re: 45 Cal Suppressor Design Review

Post by daviscustom » Fri Jan 11, 2019 8:40 pm

Your front cap could still benefit from a diet. You could open up a space between the threads and most of the front end of the last baffle. Only a shallow counter-bore is required to hold the front of the baffle captive, and the front face could be thinned out significantly.

Of course it would be all different if you are still thinking of a ring to lock the stack into the tube, and that would have the added benefit of taking all the stress off the front cap allowing it to be even lighter.
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Re: 45 Cal Suppressor Design Review

Post by Colo32 » Fri Jan 11, 2019 11:30 pm

I've settled on this for the vane arrangement. The baffles have a tight tolerance on the interlocking features, but I will likely add some method to key them as well.
Total weight as shown is 26 oz.
Total interior volume as shown is 11.54 cu in.
1.75" diameter x 8.35" long, not including adapter for the brake.
I have a shorter brake with a 12 degree lockup ahead of the threads.
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Re: 45 Cal Suppressor Design Review

Post by daviscustom » Sat Jan 12, 2019 2:06 am

How does that compare to the weight of the hybrid you have been using? It all seems to be pretty heavy built for 45 acp. The tube seems plenty thick, and the blast chamber spacer could be heavily perforated to save weight. I like the design, but if it were mine I would spend some time cutting weight, 45 acp is a low pressure round.
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Re: 45 Cal Suppressor Design Review

Post by ECCO Machine » Sat Jan 12, 2019 2:47 am

That's pretty heavy, but what you have there should be plenty stout enough for rounds like .44 mag, .458 SOCOM, even .45-70.

I can't tell if you slimmed down the baffles at all, but it looks like a pretty heavy tube, could trim some weight dog boning that. I've run 300 Ultra mag through my .035 wall Furtivus.
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Re: 45 Cal Suppressor Design Review

Post by T-Rex » Sat Jan 12, 2019 10:18 am

Yes, that's too heavy. I have an older YHM Phantom and don't use it on anything w/o a rest or bipod.

I'd still shorten the muzzle brake, the blast chamber, and possibly the distance between brake and blast baffle. You want/need the pressure in this area to help force more gas into the coaxial area. This would aid in some weight savings as well.

For the blast chamber spacer, you have some options.
-As stated, you could perforate it.
-You could bore the tube, from the exit side, and put a step in it, thereby relieving the need for the spacer.
-You could use Al and couple this with thinning from the exterior of the main tube.

As for the baffles.
-I'd keep the blast baffle on the plus side of .060
-The second baffle closer to .050
-Shave all the remaining baffles to no thicker than .035
-How thick are the vanes? Using Ti, I don't see an advantage w/ anything over, say, .025.

ETA: Reread your post and see that you're at 1.75 OD? The OP stated the use of 1.625. I would consider all of the above, in addition to the following. Reduce your baffle OD (skirt OD) to something in the realm of 1.25. The baffle stack would mimic that of a modern pistol suppressor with the advantage of the coaxial volume and features. Except designs for subgun use, narrower baffle stacks, for pistol use, tend to perform greater than those having a larger OD. The lower pressures need to be managed differently from those of a centerfire cartridge. The slimmer design uses what pressure is available to work the gas against the baffle face. The more pressure is reduced, the easier it is for the gas to slip through the bore. With a coaxial design, your allowing the gas to use most of its energy before it even gets to the baffle stack. Once it enters this area, theoretically, it has marginal remaining energy to create a loud report. Your coaxial volume is removing a substantial amount of energy that would otherwise be required to disrupt the main gas stream in a conventional sense. Ergo, tighten the stack so the baffles can do their job. :wink:
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Re: 45 Cal Suppressor Design Review

Post by Colo32 » Sat Jan 12, 2019 2:23 pm

Reduced OD of baffles to 1.25 dia.
Shortened brake
Shortened brake to blast baffle
The radial fins are .04 thick on the baffles. I increased these purely for manufacturing.
The blast baffle fins are .05 thick. I wanted to increase the contact area with the spacer to minimize embossing & to reduce likelihood of crushing or distorting fins while compressing the assembly between the caps. Also for manufacturing
lightened spacer in blast chamber
Lightened outer tube

New total weight: 21.6 oz.
Weight w/o adapter & brake: 15.7 oz.
Weight of Hybrid 46: 17 oz.

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Re: 45 Cal Suppressor Design Review

Post by daviscustom » Sat Jan 12, 2019 3:41 pm

That looks great, and I think you will be way happier with the weight. I wonder about shrinking your blast baffle spacer so that it fits against the base of the cone..... utilizing it as a diffusion screen to churn up the gasses in the blast chamber and hopefully further aid with FRP.
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Re: 45 Cal Suppressor Design Review

Post by Colo32 » Wed Feb 20, 2019 4:26 pm

Much to my surprise, I got both of my form 1's back approved today!!! 20 days from filing to approval.
:D :D :D :D

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Re: 45 Cal Suppressor Design Review

Post by #40Fan » Wed Feb 20, 2019 5:55 pm

Colo32 wrote:Much to my surprise, I got both of my form 1's back approved today!!! 20 days from filing to approval.
:D :D :D :D

Nice, now get this put together. I am sure everyone wants to know how it will sound!

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Re: 45 Cal Suppressor Design Review

Post by Plizzlewhizzle » Sun Feb 24, 2019 5:10 pm

Colo32 wrote:Reduced OD of baffles to 1.25 dia.
Shortened brake
Shortened brake to blast baffle
The radial fins are .04 thick on the baffles. I increased these purely for manufacturing.
The blast baffle fins are .05 thick. I wanted to increase the contact area with the spacer to minimize embossing & to reduce likelihood of crushing or distorting fins while compressing the assembly between the caps. Also for manufacturing
lightened spacer in blast chamber
Lightened outer tube

New total weight: 21.6 oz.
Weight w/o adapter & brake: 15.7 oz.
Weight of Hybrid 46: 17 oz.

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I made an account here just to post how freaking awesome this is.. If you can make some of these without the holes already drilled shoot me a pm.. I'll throw some money at you for sure....

Awesome design and best innovation I've seen yet for form 1 guys!! Great job

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Re: 45 Cal Suppressor Design Review

Post by Colo32 » Thu Feb 28, 2019 10:53 pm

Thanks for the complement! I cant wait to start the builds, but unfortunately it may be a while. I just took on a huge job and the mill i need with the 4th axis on it may not be free until the end of this year. I should have all of lathe work done ahead of that though.

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