The Gamo Whisperer

Gamo Whisperer

The Beemans are still telling airgunners that the BATF will come smashing down your door if you have a silencer on your airgun, but the BATF long ago sent out a letter affirming that a permanently attached silencer on a non-firearm- i.e., an airgun or paintball gun- is not a Class 3 weapon, and that it is the affixing of a device to a firearm that makes it a silencer. (Good thing, too, or they could cite everyone in possession of a small gasoline engine, since the mufflers attached to many could indeed meet the definition of a firearms silencer.) I did a post on this last year, I think, along with a facsimile image of the BATF letter and a cite of the regulations and commentary from the agency.

The people at Gamo have not been listening to the Beemans as they introduced not too long ago a rifle with a permanently attached silencer, the Gamo Whisperer. This gun has a fairly sophisticated multi-baffle silencer that is probably about as good as you’ll find on any air rifle, save for some of the really huge units seen on some pneumatic guns in England. And that brings up a good point: Exactly how effective is a silencer on an airgun?

Airguns have three sources of sound. One, the mechanical noise of the gun itself- sear breaking, piston moving, spring noise, etc. This doesn’t amount to all that much in most cases, although in a very quiet setting, a mechanically noisy gun can spook game. Second, the sound of the pellet. Again, not a terribly significant source of sound. Last, the sound of the compressed air exiting the barrel. IN a pneumatic gun, this can amount to a very loud pop- particularly in some of the big bore guns out there. In these guns, a silencer makes good sense. Most pellets travel at subsonic speeds and the sound of that air exiting the gun will reach game long before the pellet does.

Spring air guns expel a lot less air than do pneumatics, and most under 12 ft-lb guns are pretty quiet already. But when you get up to the 16-20 ft-lb range you start getting a pretty significant “pop” when you fire the gun. I’m not sure how much it spooks game, but it can be disturbing to your shooting partners- or so my friends tell me when I fired a Theoben Sirroco, which has a very sharp report, even with a simple muzzle brake/silencer permanently affixed to the barrel.

The Gamo Whisperer is billed as a “1200 fps” gun- a figure meaningless without knowing the pellet weight used to derive this figure, but if we assume a light 6 grain pellet, we’re just about up to 20 ft-lbs, and even an ultralight 5 grain pellet puts us at 16 ft-lbs. The Gamo people claim a “52% sound reduction” from their silencer- again, a rather meaningless number unless they tell us how it was derived. Sound pressure is measure logarithmically, and a 50% reduction is 3dB, which is not a halving in perceived sound intensity. Complicating things even more is the fact that you can’t simply measure the report of a gun using a standard sound pressure level meter; you need to do an impulse noise measurement.

All that aside, it’s nice to see Gamo make a solid effort at building a quieter airgun. Whether or not the “52%” figure is meaningful, I have no doubt that the device as described is sufficient to remove a lot of the sharpness of the report of the Whisperer.

airgun muzzle brakes (and silencers)

In my last post, I noted that one way of building a muzzle brake is to create a chamber in which gasses escaping the muzzle would expand and then be released more slowly. Attentive readers may have noticed that this is also a workable definition of a silencer. The typical airgun muzzle brake would not make a very good silencer- but that’s not always good enough for the BATF. It was, however, enough for Beeman to modify the silencer mounted on the Theoben Eliminators that they sell as Beeman Crow Magnums.

(It may surprise readers to learn that airgun and firearms silencers are less regulated in Europe than in the US; even in countries with very strict firearms laws, silencers are looked upon as a “good neighbor” device one uses to be considerate of those living nearby. On a visit to England some years ago I was surprised to see the wide variety of silencers available in a gun shop I visited.)

There’s a fairly hysterical article on airgun silencers posted at the Beeman site which does contain some good- but out of date- information. What it says is that a silencer is whatever the BATF decides it is, which is true. The BATF determines whether a device is a silencer by taking a device, attaching it to the end of a .22 rifle, and seeing if it attenuates the sound in any way. As many have noted, there are a lot of relatively innocuous things out there that would fit this definition, including lawn mower mufflers, plastic pop bottles, and a good many vegetables, and indeed, the BATF once prosecuted a felon who was arrested during the commission of a crime with a potato stuck on the end of his pistol.

It has been accepted wisdom for some time in the airgunning community that a silencer built into an airgun is not a prohibited device under the National Firearms Act or the Gun Control Act of 1968, since airguns are not firearms according to the BATF- but the Beeman article argues otherwise. The BATF, the Beeman site tells us, has been known to saw a silencer off a paintball gun, tape it to a .22, and do their test. And as the article notes, you may be right in the end, but defending yourself from prosecution may cost you several tens of thousands of dollars as well as your job and a good chunk of your life. But the Beeman article is well over a year out of date- and manages to misquote and misintepret a BATF ruling as well.

In ATF 2005-4, the BATF clarified matters for the airgun and paintball community. In the prologue to the ruling, it states that Certain devices intended to diminish the report of paintball guns are not “firearm silencers” or “firearm mufflers under the Gun Control Act of 1968. The ruling goes on to describe how the BATF sawed a dedicated silencer, mounted it on a .22 and acheived a sound reduction of 7.98 dB, which is is to say not very much.

But it also goes on to say that it is the removal of the silencer from the paintball gun that constitutes the “making” of a silencer- which is prohibited under the GCA. It further concludes:

Held, a device for an unregulated paintball gun, having a permanantly affixed, integral ported ballel and other componants, that functions to reduce the report of the paintball gun is not a “firearm silencer” or “firearm muffler” as defined, as the device is not one for diminishing the report of a portable firearm.

Held, removal of the permanantly affixed ported barrel and other componants from a paintball gun is a “making” of a silencer under the GCA and NFA that requires advance approval from ATF.

This should cover airguns with built in muzzle brakes and silencers/moderators as well, as airguns are also unregulated devices insofar as the BATF is concerned- but I’m not a lawyer, so use your own judgment. Making a silencer, or a muzle brake that could be construed as a silencer, and then attaching it to an airgun, or obtaining an airgun silencer from England would still still be a violation of the GCA and NFA, so do keep that in mind. If you want to go that route, fill out the necessary BATF forms, and pay the $200.

And there is always the chance that the BATF may decide one day to regulate high-powered airguns, in which case we’ll have to revisit this issue.