Ballistic differences in projectiles

[lalakai]

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With all of the different ammo types, people are usually wondering the best ammo for the different situations. No pun intended, but there is no "magic bullet" that will meet all of your needs. Nothing will beat hands on experience that you conduct yourself with your own firearms, but there are some references that can give you a head start and maybe reduce the amount of trial and error. The link will show you ballistic differences for the 5.56 and the 308, evaluating different projectiles against different materials. This isn't a comparison or eval of the 5.56 vs the 308; it's a series of results for both firearms. The download is a bit large so if you have dial up...........just shoot yourself and have someone else give you the "reader's digest" version.

http://le.atk.com/pdf/223RifleDataBook.pdf

One evaluation that the test didn't cover was angle of deflection, specifically of a projectile attempting to penetrate a windshield, and travel in the targeted path. A friend was part of a team that covered that one, and his results showed the cor-bon dpx holding an angle of penetration of 29 degrees, before the trajectory of the round was affected....fyi. He wouldn't tell me the other ammo types, but he did say that the dpx performed the best, versus the windshield.

enjoy

[Hummer]

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The site is good but it lacks several things.

1. It shows gelatin however it does not indicate the mix ratio and gelatin temp. The Army Wound Ballistic Lab has a specifc formula to duplicate human body performance parameters which requires a specific mix ratio and the gelatin refrigerated to a specific temp range.

2. Only ranges shown are 10 yards and 50 yards and as noted it appears to be that everything is good. It would have been really revealing to add 100, 200 , 300 and 600 yard performance of the bullets but then again folks would see how poorly it performs once the 223 reaches 100 yards and when passing 200 things really go down quickly. Barrel lengths could change the terminal effects with shorter barrels doing worse and long barrels doing better.

3. I have looked over it several times and cannot determine how thick the steel, drywall etc was the round went through.

4. Since they are now running Lake City it seems they would have shown M198, M855 and M855A1. M856 (Tracer) would also be interesting.

[slowz1k]

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At the opposite end of the Ballistic testing spectrum is the "Box O Truth". Though the tests lack that "controlled environment" feel, they involve penetration testing on many of the barriers someone may face in the realworld. i.e. drywall, windshields, car doors, layers of clothing, etc...
BOT also does many many firearm reviews.



http://www.theboxotruth.com/

[Hummer]

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I conducted similar testing but did it on a constructed walls with studs 12 feet apart and shot the first wall at 12 feet I think it was.

Primarly it was mostly handguns and 12 Ga.

Also shot car doors at 50 yards with handguns, rifles etc.

I got interested in 5.56 on cars after I was on an inspection tour of the SW region and was briefed on a shooting when a vehicle crashed a check point and was opened up on with ARs starting about 25 yards till it was out of sight.

They found vehicle abandoned several miles away and got their 55 gr FMJS back. They had penetrated rear window and they found bullets laying on dash as they hit front window cracking it and then falling on the dash.

I also found on car doors at 50 yards handguns did not reliably penetrate unless you managed to miss the Nader bar and the elevation mechanism which rarely happened.

Another good test is take the milk jugs, do a 3" aiming point on the side with magic marker etc and shoot them at 100 yards, 200 and 300 yards. Place a large sheet of paper about 15 feet behind and photograph the imprints the 55 FMJ makes. I will warn you quick it will be very demoralizing.

After the AR try a 308 with 150 FMJ and a 35 Remington.