Ever hear of a "Deceleration Bullet Trap" ...

[Mark Allen M]

Per Wiki: "Deceleration bullet traps direct bullets into a helical or circular chamber in which the bullet may circle until it loses velocity and drops to the bottom of the chamber for collection. For use with multiple firing positions, the helical chamber often resembles a horizontal pipe, into which bullets are directed by upper and lower steel plates. The upper plate slopes downward and the lower plate slopes upward to a horizontal slot in the side of the helical chamber. Alternatively, some narrow deceleration traps for single firing positions employ vertical plates to direct bullets into a helical deceleration chamber resembling a vertical pipe from which spent bullets drop out the lower end. Lightweight versions suitable for capturing airgun pellets are often used behind electronic scoring systems on ranges configured for ISSF 10 metre airgun events. The plate slopes are shallow (about 18° ) so bullets may be deflected relatively intact rather than disintegrated upon impact. Some deceleration traps use an oil and/or water coating to reduce friction and capture dust."

Below is a photo of a P-51D using such a device. I noticed this photo this morning on a few facebook sites. Credit to Granger Davis‎.



Also per Wiki: "Below a Conceptual schematic cross-section of a deceleration bullet trap with black lines representing steel plates: Bullets entering from the left are deflected into the top of the deceleration chamber. Bullets are then deflected clockwise around the deceleration chamber until they lose kinetic energy and fall out the bottom of the deceleration chamber."
https://en.wikipedia.org/wiki/Bullet_tr ... 4oEC7VuCoA

[Xrayist]

I remember in the late 60's-early 70's, I think, there was something similar for indoor shooting of .22 LR. It looked something like a French Horn, (the best I can describe/remember it).

[wendovertom]

But why?

Tom P.

[4RG.I.'S]

But why?

Tom P.

It's a matter of space and safety. .50 caliber bullets fly a long way and need to be controlled and contained. With this system it can be contained in a very small area. That being said, I'll bet it was pretty noisy!!
It is common at indoor gun ranges as well, I had plans for one in my house for a bit.

[Mark Allen M]

But why?

Tom P.

"A bullet trap is a device to stop bullets fired at a shooting range. The bullet trap may also provide means to recycle bullet materials and/or prevent release of toxic metals from the shooting range. Bullet traps typically use friction, impact, or deceleration to stop bullets. Some bullet traps include a vacuum system to filter dust from air within the impact and/or capture area."

[wendovertom]

It makes sense, for purely testing the firing mechanism. I guess what threw me off is here in Wendover there is a huge bore sight gun "butt". Essentially a 20 foot tall dirt mound with timber reinforcements on either side and a big sand "trap" the the gun(s) would fire into. You would need some range to make sure that the alignment was correct rather than just, do they fire or not.

Thanks,

Tom P.

[hardlanding]

Indeed, as a kid, we had a consumer version of this in our basement, which is where my father taught us how to shoot .22-caliber rifles. It was basically a cast iron, hollow 4-sided pyramid with the base removed, turned on its side so that the open base (approximately 3 feet across) faced horizontally, with a clip for hanging paper targets, and the whole thing on a stand so that it was maybe 3 feet off the floor. The pyramid shape channeled the bullets into a round chamber where they would spin around until they lost enough kinetic energy to drop vertically into a tin can.

I know it sounds crazy now, but in those days (late 60's), it just seemed fun. (And it was treated with the utmost respect for safety and proper gun handling procedures.)

[Chris Brame]

But why?

Tom P.

And where and when? No markings on this bird other than a faint "210" where the star-and-bar should be.

[Mark Allen M]

Chris I'd say this was at Inglewood CA, late 44 or early 45.

[Cvairwerks]

We used to have one rated for up to 30 mm at work. I think the last time it was used was about 1984 or so. It took weeks to remove it when a new building went up at the same space. They had to clean up lead from all the way back to 1941 out of it.

Tom: with optical alignment tools, the need for distance is greatly reduced. With a little measurement and some high speed cameras, the convergent point can easily be determined after alignment. If I remember correctly, the convergent point for a Mustang was somewhere around 450 feet.