FX Crown noise...and moderator

[aldea6]

Hi , 

It seems , regarding a lot of opinions , that the FX Crown would be THE airgun to buy , in terms of accuracy , consistency,...and so on .I could believe so , because I 've a Wildcat .25 and an FX Boss, and they are just awesome. Just one point worries me : is the Crown , in .25 or .30 cal really backyard friendly ?? I mean , even with a DonnyFL moderator , how does it compare with the Wildcat or the Boss ( calibers being identical , of course ) ? When looking at some videos , it seems louder , even with the shroud extended.

Thanks for your opinions

Aldea6

 

[Bob_O]

I would say mine in 22 and 25 are backyard friendly with a suppressor at normal power levels. 

 

[STO]

So the answer is, as factory, ABSOLUTELY NOT. I've been doing a lot of testing with two FX Crowns, one in .22 and the other in .30, testing various commercial moderator designs as well as my own designs. The short answer is that with only the shroud extended the .30 Crown is extremely loud. There is also another issue (and I know I'm going to get in trouble for putting a pin in the accepted dogma of bigger is better) which is that as moderators get larger, specifically increase in diameter, their ability to effectively dampen sound is reduced dramatically so your "minimum loudness" actually becomes quite loud. This has been true of the commercial designs I've tested (namely Donny and Clague) as well as my own personal attempts (Mus and larger form factors, and I just had another round of failures with large moderator designs) 

Unfortunately I've got a massive pile of data to sift through on three different projects now, so it is going to be a little while before I have a writeup on my experiments with the .30 Crown. Here are the test results of commercial designs on the .22 Crown (and I'll update that thread with info on the .30 Crown as I get around to it):
https://www.airgunnation.com/topic/fx-crown-bespoke-moderator-tesla-gas-diode/page/5/#post-453278

The factory shroud extended on the .30 Crown is about 637, using the same units as in the above linked test. That is the loudest airgun shot I've ever measured. 

If you have any other questions I'd be happy to try and answer them for you. I don't have all the answers, far from it actually, but I'll do my best. Everything I do/know is data-driven though. 

I hope that helps. 

 

[bucketboy]

There is also another issue (and I know I'm going to get in trouble for putting a pin in the accepted dogma of bigger is better) which is that as moderators get larger, specifically increase in diameter, their ability to effectively dampen sound is reduced dramatically so your "minimum loudness" actually becomes quite loud. This has been true of the commercial designs I've tested (namely Donny and Clague) as well as my own personal attempts.

^^^^exactly this^^^^. Nicely put!





Bb

 

[Nicklandon]

My .25 crown is definitely backyard friendly for me

 

[Bob_O]

My Crown 22 pushes 46fpe and the Sumo does a great job keeping it quiet. In 25 caliber with 500mm barrel, same power level, same suppressor, same results.

Doesn't look too shabby either.

 

[Macros]

There is also another issue (and I know I'm going to get in trouble for putting a pin in the accepted dogma of bigger is better) which is that as moderators get larger, specifically increase in diameter, their ability to effectively dampen sound is reduced dramatically so your "minimum loudness" actually becomes quite loud. This has been true of the commercial designs I've tested (namely Donny and Clague) as well as my own personal attempts.

^^^^exactly this^^^^. Nicely put!





Bb

I'm with these guys on this 

 

[aldea6]

Thanks a lot for your opinions a for your incredible work on moderators. it will help a lot.

 

[jking]

I've never shot a Boss but I am shooting a 30cal Crown pushing 44.75gr at 895. I wouldn't call it loud but maybe not backyard friendly depending on your area. It's fine in my backyard but my nearest neighbor is about 80yds away and they would have to get off the video games, TV and couch to every hear my shooting. If you have a noisy neighbor just across a joining fence there's going to be several guns considered not backyard friendly. If the Boss is similar to the Royal as far as dead space between the end of the air stripper and the end of the shroud that's about the same dead space as my Crown extended. I would therefore think the Crown and the Boss might be fairly similar. 

Jking