Benjamin 397 something inherent makes it louder than other pumpers?

The 397/2 are pretty powerful for a multi pump. And have a good amount of snap to the report. Especially at full power. And there is no easy way to quiet them down. They are much quieter at 3-5 pumps but still loud by today’s standards and expectations for “backyard friendliness”. 
the new Crosman 362 is a multi pump based on the 13xx multi pump pistols. Lots of potential for modding including the Crosman steel breech for better scope mount ability and muzzle devices can be easily added for stealthy backyard shooting. It’s expected to do about 12 fpe. 


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While no able to anwser question directly, let me make a factual statement which should enlighten you and likely give a round-a-bout anwser.



Pneumatic air guns be them SSP, Multi pump, Co2 or PCP universally are based off PRESSURE with the Volume of air while important as caliber increases takes a back seat to pressure.

Any pneumatic air gun will become louder if there are increases in air volume exiting after pellets gone.

An SSP is a prime example of fairly high pressure and very low volume sounding like a stick breaking when shot.

Multi pump guns don't and most can't create high pressure relying on Volume of air. This is why MPP guns make such a loud BLAPP.



Think your case is, while each MPP may pump up to @ equal pressures, it is the Volume of air being released that is likely causing the sound difference.



Scott S
 
The 397/2 are pretty powerful for a multi pump. And have a good amount of snap to the report. Especially at full power. And there is no easy way to quiet them down. They are much quieter at 3-5 pumps but still loud by today’s standards and expectations for “backyard friendliness”. 
the new Crosman 362 is a multi pump based on the 13xx multi pump pistols. Lots of potential for modding including the Crosman steel breech for better scope mount ability and muzzle devices can be easily added for stealthy backyard shooting. It’s expected to do about 12 fpe. 


7BF502E8-6E1F-4EE9-B5D9-832507B3646C.1612102344.jpeg


The long pump handle should make this one a interesting shooter.