In both audio clips the larger 8.5mm sized hole was shot first, which was the loudest.. what are you trying to say?
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Using Or Have Used A DonnyFL Sumo?
- Thread starter MikeAllen
- Start date
You are right. Look at the dB data for each bore size, as measured from the side. The smallest bore is not the quietest. These results follow the same pattern are three other data sets posted earlier in the thread, where the dB reduction rank order does not follow the bore diameter in the expected rank order. This suggests there is an optimal bore clearance, rather than just "tighter is better".
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With all due respect, the test was done with a 13 year old camera then the sound was separated from the video.. a correct test would've been done with a proper decibel meter.. who is to say that the camera could pick up on the differences in all frequencies?? I'm not trying to dig deeper and deeper into this or sound like I'm trying to dispell your research.. I've watched plenty of airgun videos where they do the "before and after" test with moderators and they both sound identical.. whereas I'm sure it didn't sound like that to the person performing the comparison..
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You are welcome to received the three muffler set used for the above test, and run your own evaluation; with any meter you deem fit.
The guy using the 13 year old camera routinely does a spectral analysis on mufflers he sells. That is why I invited him to run the test; using his standard test methods. He might put up some spectral graphs today. If you have doubts about the value of the evaluation, I welcome you to post them in reply to that three muffler bore clearance post, linked above.
I intend no disrespect for your opinion either. I would welcome such an analysis done by an independent expert with access to the best equipment. The other reason I asked this particular gent to run his test protocol is because he has a lot to say about what others are doing wrong. I essentially asked him to show us, rather than tell us. So this is where we are. The same invite is extended to you, or your proxy. Show us how it is done. Let's see some confidence inspiring data.
The three mufflers are identical, except for the baffle bores being 6.5, 7.5 and 8.5 mm in diameter. One would think there would be a massive difference in performance. The contention is that the performance difference is not that large; hence the advice to go up in baffle bore diameter, to be sure there is no clipping.
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I'm running a Sumo on my Mav VP .25, back yard friendly. I've yet to find a moderator that works better than a DonnyFL and several that are far worse than nothing.. Remember length counts more than diameter, no pun intended.
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@MikeAllen I use a .25/.30 Donny FL Sumo on my Evol .30
I use a .22/.25 Donny FL Tanto on a Brocock Bantam Sniper HR .25 and my Prod .22. No issues with either moderator on any of the guns mentioned. I’ve read of the manufacturer suggesting getting a moderator one size larger, not two. I use them as mentioned above. Your mileage may vary.
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That difference you are citing is most probably within the margin of error. I wouldn't interpret it as confirmation that a smaller aperture is likely to ever result in less suppression.
I like the idea that there may be an optimal clearance though. If that proves to be the case it will likely be dependent upon caliber.
I did, however, increase the clearance in my designs because of the results of that study.
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I have a Sumo (.25) on a TalonP in .177
Works great.
Tried it on a AEA challenger pro in .25 and was ok but the Buck Rail (.30) was better.
Works great.
Tried it on a AEA challenger pro in .25 and was ok but the Buck Rail (.30) was better.
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