atec's are good rimfire mods, but not sure how efficient they are on air rifles/ pistols. swift stumpy is a very good mod for air pistols. i use one on my falcon and eb20. you might want to try taking readings with a decimeter next to pistol. and then another set of readings about 10/15m away (or the distance closest to the range you tend to shoot at) to get a 'realistic' reading, as this is the distance others or quarry will be experiencing (if that makes sense). the firing point reading is only the sound level you'll be experiencing and not others, if thats your concern...
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