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Author Topic: Minimizing damage in test fired .223 rem bullets  (Read 67238 times)

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Michael Courtney

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Minimizing damage in test fired .223 rem bullets
« on: September 08, 2006, 10:29:28 AM »
It seems to me that there may be a need for inexpensive methods to minimize the damage in test fired .223 bullets.  There are expensive ways to solve the problem, but such capital expenditures are probably not realistic for examiners who only encounter the need to test fire .223 bullets once a year or less. 

I am bouncing around some potential ideas to reduce damage in test fired .223 bullets using inexpensive and common materials that would be useful for examiners who encounter the need to do so infrequently.

What do y'all think of the value of this research idea?  Is this problem already solved?

Thanks,

Michael Courtney

Offline Charles Clow

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #1 on: September 08, 2006, 10:33:23 AM »
The cotton box seems to work fine.

CMC

Offline Geoff Bruton

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #2 on: September 08, 2006, 11:23:43 AM »

I agree with Charles - the cotton box is a very cost-effective and practical way of collecting high velocity projectiles.

Another alternative is safely downloading the propellant charge such that the velocity is reduced to the point where shooting into a water tank is now practical - below 1700 f/s rings a bell...

Good luck, and best wishes to all,
Geoff.
Geoff Bruton
Ventura County Sheriff's Office
Forensic Services Bureau

Offline Axel Manthei

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #3 on: September 08, 2006, 02:53:31 PM »
We have done the downloading for years until we found out that downloading might influence  (.... not as intense as ... ) traces on the bullet surface. From this moment on we went to the full load and the moving cotton box.

Cotton seems to work best. But it also depends on the different typs of cotton.

Greetings

Axel

Offline Bob Shem

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #4 on: September 08, 2006, 02:58:47 PM »
http://www.afte.org/forum/smf1/index.php?topic=1797.msg8164;topicseen#msg8164

The post above offers another option.

For non-members here's the gist:

Why the foam?

This design is one that I used as the basis of an AFTE seminar presentation in Houston, Texas in 1991.

The presentation was entitled "Recovering High Powered Rifle Bullets at Full Velocity Without Damage".

The reason for this experiment was to find a method to replicate most closely the interior ballistic conditions of the shooting without destroying my test shots in the process.  High powered rifle bullets, particularly the soft points and 223s, tend to come apart in the water tank - unless they are downloaded.

Downloading cartridges was found to affect the markings on the casework bullets in question so I experimented with different bullet collection methods until I came up with the system in the drawing.

My experimental setup was more humble than the system in the drawing.  It consisted of two open-ended four foot tall stackable plywood boxes packed with blocks of open cell polyurethane foam and placed on top of a 55 gallon plastic drum full of water.  I did my shooting from a construction scaffold.

My cheapo setup was total Rube Goldberg, plus I had to do my shooting on the weekend (when no one else was in the building) in our vehicle inspection area with the works down in the grease pit.  This was not the best test firing arrangement for the long term because some of my co-workers are nervous of discharging firearms.

The foam will take a considerable number of bullet passages before replacement is necessary.

The foam stays in place quite well with no (or very little) foam falling from the array into the water tank.

I have attached a photo of two 69 grain Sierra boat tailed hollow point bullets fired back in '91 for this experiment.  The bottom bullet was fired directly into water.  The top bullet passed through eight feet of foam before being stopped by the water.  Both bullets were fired in their factory load condition with no downloading or modification of the ammunition or firearm.

click on the photo for a larger view
« Last Edit: September 08, 2006, 03:09:02 PM by Bob Shem »
Robert J. Shem, 4900 Buckingham Way., Anchorage, AK  99503, ph 907 952-2254, bobshem@alaskan.com

Offline Charles Clow

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #5 on: September 08, 2006, 03:03:31 PM »
Inexpensive Bob . . . inexpensive.   :)

CMC

Offline Bob Shem

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #6 on: September 08, 2006, 03:11:54 PM »
Quote
Inexpensive Bob . . . inexpensive.

A couple sheets of plywood, some 2 by 2 lumber, a large plastic barrel, and a few cubic feet of poly foam, and you are in business. O0
Robert J. Shem, 4900 Buckingham Way., Anchorage, AK  99503, ph 907 952-2254, bobshem@alaskan.com

Offline Charles Clow

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #7 on: September 08, 2006, 03:21:19 PM »
You forgot the ladder.    ;D

CMC

Offline Scott Doyle

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #8 on: September 08, 2006, 04:04:42 PM »
OSHA would require a safety harness and hard hat too. 

It sounds like something cool to set up and demonstate at the state fair in our State Police "Safety Town".  All of the kids on trikes would really get a kick out of it!

All kidding aside though it looks like a good concept.

Scott

Offline Bob Shem

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #9 on: September 08, 2006, 05:53:08 PM »
Quote
You forgot the ladder

No ladder is required, but an umbrella helps keep you dry when the water splashes back.  :D
Robert J. Shem, 4900 Buckingham Way., Anchorage, AK  99503, ph 907 952-2254, bobshem@alaskan.com

Offline Charles Clow

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #10 on: September 08, 2006, 06:18:17 PM »
Wow, you guys up in Alaska have some really nice uniforms.   O0

Is that lil' Debbie hanging on your leg?  What's that about?

CMC


Michael Courtney

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #11 on: September 08, 2006, 11:53:20 PM »
Good discussion, and lots of good ideas.  But do the cotton box and opened cell foam really stop the more fragile (including plastic-tipped bullets) like the Hornady VMAX with minimal damage?   

I haven't tried it, but a 40 grain VMAX at 3600 FPS would seem to be the extreme validation test for any bullet stopping method. 

It seems like one might have to split the difference here: download to 2800 FPS or so so as to not overly affect the rifling marks and use an improved stopping medium to slow the bullet to 1200 FPS before it hits the water.  I guess the open question is what length of styrofoam peanuts is needed to slow a .223  bullet from 2800 FPS to 1200 FPS.

Thanks,

Michael Courtney

Offline gunguy05

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #12 on: September 09, 2006, 12:56:13 AM »
I have rigged up a method of shooting through an old BP vest.  It seems to slow down the bullet ennough that it comes out in one piece almost every time.  I have done this with .223 and 7.62 and hadd success with both....

Offline Charles Clow

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #13 on: September 09, 2006, 04:36:07 PM »
I have personally fired the 223 Remington caliber Winchester 50 grain Ballistic Silvertip which has a polymer tip and a muzzle velocity of 3410 fps into the cotton box with zero deformation.  In fact, I can't ever remember having a problem with bullet deformation in the cotton box.

Having said that, this is still a worthy research topic.  I always enjoy hearing about alternative methods.  It's always good to have a backup plan.

Keep up the brainstorming.

CMC

Offline Ray Cooper

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Re: Minimizing damage in test fired .223 rem bullets
« Reply #14 on: September 11, 2006, 08:51:20 AM »
  I guess the open question is what length of styrofoam peanuts is needed to slow a .223  bullet from 2800 FPS to 1200 FPS.

I am not sure you could make a box long enough using styrofoam peanuts.  What you need is tightly packed layer's of cotton or cotton fiber waste with a few of phone books at the back.  I have only had one time that a bullet went completely through an eight foot box and that was shooters error, forgot to replace the phone books at the end.  The only problem I have had with a cotton box is when I have used all lead bullets.  The cotton or cotton fiber waste tends to leave wipe marks on the bullets.  It also helps to partition the box with a sheet of paper about every foot to help find the bullet easier. 
Ray Cooper
834 Cooper Rd.
Dubach, LA.  71235
rballistic@gmail.com

 

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