I have been trying to get the WA law banning silencer use changed for the last several years. Part of the problem is that I keep hearing from my Senators and Representatives that silencers are illegal in the United States. To help clear a few things up, I am putting together a video explaining silencer design, legalities and a demonstration at a rifle range.

http://www.youtube.com/watch?v=fbaOZLTex5I part 1
http://www.youtube.com/watch?v=HGBjywtiCQc part 2]

This is the rifle range footage I shot and edited using a Canon HF21 and Pinnacle Studio version 9. Comments are welcome.

Ranb

Nice job ranb! Very dispassionate commentary, just what is needed for educational material. Might be more convincing if you shot right handed however(!).
Quite convincing. However I was under the impression that some microphones automatically "cut back" when very loud sounds were received, so the actual sound of the unsuppressed rifles might be even louder. Did you really use the same suppressor for the 308 and the 338?
Peter.

Same silencer. When recording the .308, 5.56 and 338 rifles, I reduced the volume way down on the camera's external microphone. When I captured it on the computer, I increased the volume just enough to avoid distortion. This way I was able to highlight the difference in suppressed and unsuppressed noise. My older camcorder with the built in mic made them sound almost the same.

When I was waiting for the form 1 to be approved (30 cal) I was also making the 338 RUM rifle from an M700 action and Pac-Nor barrel. I did not dare use aluminum downstream of the blast baffle like I did for the 5.56 can so I had to carve them all out of 4130.

I decided that I only wanted to toil over one silencer for both rifles, so I made the bore large enough to use on the 338. So while the 338 has more than double the powder charge, the closer fit on the baffles makes up for it a bit.

It weighs almost three pounds, but I am happy with it. When I suppress my AR-10, I will make a smaller, lighter muzzle mounted can for it instead of the two point mounted can on shown in the video.

Ranb

Latest versions of the video.

http://www.youtube.com/watch?v=qBqn8zi0wK8 part 1
http://www.youtube.com/watch?v=r_M46TeOTgs part 2


And some other stuff I shot while in Vegas.

http://www.youtube.com/watch?v=lPWaHx0DXmQ Ruger 10/22
http://www.youtube.com/watch?v=TkIhNtWCz6c Walther P-22
http://www.youtube.com/watch?v=Dk-I9UF2HY4 458 Socom
http://www.youtube.com/watch?v=3lnBE9H_d8I 338 Remington Ultra Magnum
http://www.youtube.com/watch?v=69lxfhniL2g 308 Winchester
http://www.youtube.com/watch?v=cEQoXmoYVfo 510 whisper
http://www.youtube.com/watch?v=AQ5_UJTe1Z8 AR-15’s
http://www.youtube.com/watch?v=BGoPE7VQ9GY Nagant revolver

and a radio control model of a C-17

http://www.youtube.com/watch?v=v_ZWQu8QaCA

Ranb

Very nice work, as you noted it's extremely difficult to record a gunshot.
Most people just give up trying and steal a sample off something.

I'd guess that home video cameras have automatic limiters on the audio input. Probably noise gates as well. So you will have a squashed sound and loose a lot of the natural reverberation.
I don't think you could get around that unless you got a studio quality mic and a separate recorder then synced the sound of the shot on in post production.

I was talking to a guy I know in Vegas about using a quality mic that would pick up very loud noise without distortion. The list of inexpensive mics with their own power supplies (required by my Canon HF21) is very short; none at all.

I think I will try to make a thick foam rubber housing to block most of the sound. This might allow me to actually record the 1000 times difference in the noise intensity without distortion; I hope.

I wonder how well a 1/4 inch mic made for a noise meter would work?

Ranb