Barrel testing set up.

[jonsidneyb]

I was wanting to know if there is a way to fire a cartridge out of the barrel of an autoloading pistol while not in a gun for testing purposed.

I think years ago I saw a picture of such a set up.

Thanks
Jon

[Chipperman]

It can certainly be done. The trick is doing it safely.
I've seen rigs that people like Doug Koenig have made to test barrels.

You need a device that will hold the barrel in place and also provide a "bolt face" so the cartridge case cannot exit the chamber as the bullet leaves the muzzle.

[jonsidneyb]

Here is what I am wanting to test. I want to learn if a barrel that cannot recoil or move in anyway, If it has a measurable velocity advantage over the same exact barrel that has a human that is affected by the recoil and has started the inertia of the slide movement. I know the bullet has already left the barrel before these events all take place but the energy that does this was still exerted in the other direction.

Are there any published tests where this has been done. The same barrel used in a fixed position compared to a functioning autoloading pistol.

Thanks
Jon

[jonsidneyb]

Has Doug Koenig or anyone with a fixed barrel set up recorded velocity findings???

[owen]

David Sams sells a barrel testing fixture.

http://www.samscustomgunworksusa.com/pages/724931/index.htm

It's 3 rows down. It works pretty well, but you need a good way to fix it to a bench, and a good study fixed bench. It's a pain to get it aimed for accuracy testing. I used a boresight laser.

Keep in mind that it is expensive, because they are handmade by a well known gunsmith, one at a time.

[jonsidneyb]

Owen,

Do you have one of these and a chronograph?

[owen]

I bought the barrel tester on behalf of acompany I was working for. I no longer have easy acess to it.

Another problem you may have is that chronographs are not particularly precise. The velocity difference between a fixed barrel and a firearm mounted barrel may be overshadowed by the velocity difference to to the weather woarming up as testing goes on.

Why id you bring up Doug Koenig? Is he using some freaky gas gun now?

[Jim Watson]

Probably be cheaper to modify a cheap pistol to lock the slide shut in the manner of the old Hushpuppy.

[jonsidneyb]

I brought up Doug since Chipperman indicated that Doug has used barrel testing setups.

This I guess is trying to see some science in this and how it affects my thinking on various guns. I am wondering if even the recoil affect on the human body and the slide has any affect on velocity.

[owen]

I think you are making mountains out of molehills.

Is there a velocity difference in a fixed barrel gun versus a moving barrel gun? Absolutely. As much as 1%. (according to a knapkin calculation I just did.) In a typical 1200fps 9x19mm loading, that is a whopping 12 fps.

However, the other factors that make an effective defensive tool have a much greater bearing, like, can you hit what you are shooting at?

In fact most of those factors are software problems, not hardware problems.

[jonsidneyb]

I am satisfied with Autoloaders and Revolvers as defensive tools and am not looking for something that will gain velocity of my carry equipment. I guess this is more of an achedemic look at things for me. I just want to understand all that is going on to broaden my mind.

[owen]

How is your algebra?

[jonsidneyb]

can you show me your equations? I someday would like to see someones real world test or find away to do it myself someday.

[owen]

Give me a few days to type it up, and check it over. If you don't see it by Thursday, send me a PM.

I will proably attach it as a Word file, because equations are easy to do in Word.

[jonsidneyb]

Thanks
I appreciate it

[Chipperman]

Doug Koenig uses it to test the barrels for accuracy. He buys a bunch of barrels at once and uses the best for competition.

I don't know if he does any chrono work with the setup.