Ballistic gelatin test results : .223 Remington vs. Car Door (FBI test # 3)

[Brass Fetcher]

Cartridge : Federal Premium 55gr Trophy Bonded Bear Claw

Firearm : 16.0" barrel, gas-operated action with 1/9" twist rate

Block calibration : 10.4cm at 590 ft/sec (estimated)

Single shot fired through two pieces of 20 gauge galvanized sheet steel, offset 4" from each other (weakest part of a car door) and two sheets of 12 ounce denim fabric (light clothing). Distance from muzzle to the first piece of sheet steel was 7 yards.

Shot impacted ~ 1.5" right of center, causing the sides of the gelatin block to be destroyed. Please note that this is not due to the bullet, so much as it was due to poor shot placement. Even though this particular round has tested to be very impressive in bare ballistic gelatin.

Bullet impacted at an average velocity of 2685 ft/sec, penetrated to 13.0" and expanded to 0.455" average diameter. Retained weight was 52 grains.

Velocity for the calibration was estimated due to a drained battery on the chronograph - discovered of course on the firing line. The BB gun used for calibration averages 587 ft/sec for 16 pumps ... so I shot the block at 18 pumps and am calling it 590 ft/sec. Velocity for the tested bullet was obtained for a 10 shot group (at an earlier date) at 5 yards from the muzzle.

Thank you,

JE223

 

[quatin]

has anyone done .223 tests with the heavier rounds such as the 69 sierra bthp? Also, nice photos, what is 2nd photo of? Is that the BB shot?

 

[taliv]

visit the B&T ammo labs

 

[Metapotent]

Bullet impacted at an average velocity of 2685 ft/sec, penetrated to 13.0" and expanded to 0.455" average diameter. Retained weight was 52 grains.

Is that the velocity when it impacted the first metal sheet, or the ballistics gel?

 

[Brass Fetcher]

My chrono's skyscreens have taken everything from .32ACP to .257 Weatherby - so now I am careful to keep them from getting hit. That would be more characteristic of the velocity impacting the first piece of steel. Putting it behind the steel would subject it to lots of potential damage. FWIW, there >was< spalling of the metal at the point of bullet exit, IE the steel sheet sprayed out in small steel dust with the bullet.

Yeah, that photo was mainly to illustrate the penetration depth of the calibration BB. Some heavier bullets would be nice in .223, although I am very happy with the performace of the 53- to 60-grain bullets that I have tested. Someone sell me on the heavier bullet idea.

JE223

 

[taliv]

Someone sell me on the heavier bullet idea.

seriously,
http://www.btammolabs.com/tests.htm

if this doesn't sell you, i don't know what would.

Readers may recall that other ballistic testers have reported the magazine length 100 grain round as among the most impressive terminal performer ever tested.

 

[Brass Fetcher]

The Mk262 Mod 1, as well as the 77gr look to be very ill-tempered bullets. Having read over their procedure, btammolabs looks good to me... I'm not sure what I could do to improve on their findings?

What sort of twist rate is needed to fire these heavier bullets? One of the criteria that I have when deciding what round to test is ' is it generally available to everyone?' and 'is it current production?'

JE223

 

[taliv]

i think the way you'd improve on their stuff would be submitting your own results to them after duplicating their procedures as well as possible. note they have two sections, one they did, and one for submissions.

as for spinning them, most of them require 7-8 twist i think. you can get sierra 69/77/80/90g bullets all day long. berger and hornady make those 75 grainers

 

[Brass Fetcher]

I try to stay away from doing tests that others have done, because I'm thinking about statisical validity. IE, the results that I have gotten, or that BTammolabs has gotten should be repeated at least 10 000 times, before 'statistical validity' is reached. And that's a lot of gelatin!

 

[taliv]

actually, i meant submitting samples of bullets they haven't already done. you know, odd cartridges, or a series of common cartridge handloaded to 5 velocities. e.g. wouldn't it be interesting to see a 55g FMJ at 3200, 3100, 3000, 2900, 2800 fps? or even a good old fashioned .451 230g hardball at 700, 800, 900 fps

 

[Brass Fetcher]

I see. I usually do post my tests to my website : www.brassfetcher.com . So if I do anything like that it will probably end up there.

The .45ACP FMJ isn't really necessary to test - a common profile like a 'FMJ' profile can be predicted by using formulae/graphs from MacPhersons 'Bullet Penetration' book, at any practical velocity IIRC.