Site Notices
11/20/2014 4:05:39 PM
  Previous Page
Page:  / 5
Author
Message
tatjana
Team Member
Offline
Posts: 1355
Feedback: 0% (0)
Posted: 12/10/2002 3:08:16 PM EST
[Last Edit: 12/10/2002 4:53:32 PM EST by tatjana]
[Brouhaha]: "From the land of sky blue waters..."
[Tatjana]: "...Waaah-ters..."
[Brouhaha]: "...From the land of pines, lofty balsam, Comes the beer refreshing, Hamm's the Beer Refreshing."
[Together]: "Haaaaaamm's...."



Well, ok, we can't exactly promise you free beer (even Hamm's), but we can bring you:

B&T Ammo Labs Fragmentation Experiment #4:

"Multiple Round, High Velocity 5.56mm 100 grain performance in bare gel."

Tatjana von E. and Derek W. F.

This experiment was designed to assess the terminal performance and wounding properties of magazine length 100 grain "Open Tip" rounds in 10% calibrated ballistic gelatin. Readers may recall that other ballistic testers have reported the magazine length 100 grain round as among the most impressive terminal performer ever tested. Because of their compatibility with stock AR15s (given a fast twist rate) and the defensive potential these rounds presented we felt testing them to be exceptionally important for our purposes. After some significant efforts we obtained a series of 100 grain rounds for testing. Because of the sensitive nature of the 100 grain rounds and their development, some details of the rounds themselves are withheld.

As usual, the outstanding support of the AR15.com community makes this experiment possible. Particular thanks go to AR15.com member "Hi-Vel" for selflessly fabricating our molds in a hurry (and flat out refusing to be paid) after a disaster with old ones. Thanks to "Captain K." about whom we can say no more. Thanks also to the anonymous AR15.com member who's loading expertise was instrumental in assessing the rounds.

Specifics and Conditions:

Ammo: .223 100 grain Copper Alloy Jacketed Open Tip rounds.

Rifle: Preban Colt 20" A1 with Government Profile 1:7 Barrel and A2 Flashhider.

Temp: 55 degrees. 60% Humidity. Pressure: 30.19 in/Hg. Alt: 213 feet.

The target was a FBI spec block (20x20x50cm) of 10% ballistic gel (9 parts water, 1 part gelatin by weight). Vyse ballistic gel was prepared according to FBI ballistic gel testing protocols. Additionally, gel temperature was not permitted to exceed 37 degrees C at any time during preparation.

Following preparation, gel was stored at ~4 degrees C and permitted to cure for 72 hours before testing. Gel was tested within 15 minutes after removal of blocks from refrigeration. Gel blocks were calibrated with a .177 caliber BB immediately before testing. (Optimum = 8.5cm @ 590 fps). Our results were within accepted calibration standards for ballistic testing without penetration measurement adjustment.

Procedure:

10 velocity tests on the rounds were conducted using a Oehler Research 35P chronograph 15 feet from the muzzle. Results are included below:

2476 fps
2456 fps
2503 fps
2447 fps
2454 fps
2457 fps
2430 fps
2460 fps
2476 fps
2411 fps

Calculations on velocity data:

Mean: 2457.0
Median: 2456.5
Standard Deviation: 25.4
Q1: 2442.8
Q3: 2476.0

After some alignment shots, targets (bare gel blocks) were placed 16 feet from the muzzle and each subjected to a single round. Velocity of the projectile was again measured at 15 feet, 1 foot before the gelatin block.

Multiple blocks were shot.

The blocks were examined, photographed and then dissected into slices. Slices were photographed to measure and record wound profile size. Fragments were then extracted and their penetration depth measured and recorded. Fragments were organized according to penetration depth and photographed to record fragment distribution throughout the wound cavity.

Shots exhibited similar ballistic performance- only a 3.5" variation in penetration between all shots was observed with one remarkable outlier- which penetrated substantially lower than the group.

The extremes of performance (measured in penetration) are photographically reproduced here, i.e. the Highest ("High") and Lowest ("Low") penetrations in terms of inches of penetration from the gel face are shown.

Results notes/Observations:

1. Velocity of our highest penetrating round ("High") immediately prior to impact with the gel face was 2450 fps.

2. Velocity of our lowest penetrating round ("Low") immediately prior to impact with the gel face was 2440 fps.

3. Velocities mirrored velocities observed in the gel testing of 100 grain rounds in other ballistic experiments of which the authors are aware.

4. Fragmentation of the 100 grain rounds was as dramatic, even more dramatic, than expected. "Spectacular" was a frequently used descriptor. Neck length was very small (generally under .50"), and fragmentation began immediately. The combination of exceptional fragmentation and extremely deep penetration (up to 14.50") makes the round a good defensive option. It should be noted, however, that the "Low" round did not exceed 12" of penetration (10.75" only). Despite this, fragmentation of the "Low" round was explosive. (See Figure C).

5. Initial weight of the projectiles averaged 97.2 grains. Recovered weight of the projectiles averaged 82.2 grains.

6. The largest recovered fragments appeared to be part of the bullet's base and jacket structures. Average largest recovered fragment was 22.5 grains. (76.9% fragmentation). This was usually found at the extreme of the wound cavity. (Inch 12.5-14.5).

7. All rounds appeared to produce two specific cavity "blooms" where larger cavities and more dramatic fragmentation in the gel seem to indicate the bullet was traveling with a 90 angle perpendicular to the direction of travel (See Figures H and I). The "blooms" are joined by a short section of narrower tissue damage. This suggests that the round rotates 180 degrees during the course of travel and as it passes through a 90 degree orientation to the direction of travel twice leaves the dramatic tissue damage and fragmentation seen in the "blooms." Fragmentation and tissue damage in the second "bloom" is the most dramatic. Probably because by the second half of its 180 degree rotation and after having portions of the jacket stripped away the round's [star trek moment]structural integrity[/star trek moment] is minimal and fragmentation more dramatic. Wound cavity at its extreme, measured by gel fractures, was usually in about the 8th inch of penetration and spanned a rather significant 5.75-6". Fragments were often deposited at the extreme edges of these fractures.

8. Some rounds started to veer off their original path after about 10" of penetration. The veer was not generally significant (1" - 1.5" from straight line path).

9. Dramatic fragmentation makes exact determination impossible but all rounds seems to have ended their path "tail first."

10. Fragmentation was so significant and left so many small fragments, primarily of lead core, that there was little hope of recovering them all. Many fragments were far smaller than fine beach sand or table salt crystals.

Conclusions:

At close range these rounds are devastating. They are clearly the most dramatic fragmenting and cause the most tissue damage of any .223/5.56 round tested so far. Some concern accompanies the shallow penetration of the "Low" round, but it may very well be compensated for by the exceedingly violent tissue damage exhibited in the gel shots. We also suspect this particular round to be a fluke. Still, additional testing should concentrate on penetration depth.

After sectioning it was clear that wound cavity volume throughout the wound path is FAR greater than with M193 or any other tested fragmenting rounds.

Because of limited penetration of the "Low round" and the uncertainty of fragmentation at lower velocities (e.g. from a 16" weapon), we cannot yet make a defensive recommendation for this round. Pending a resolution of the penetration issue and lower velocity testing we may revise this view.
"...no secret so close as that between rider and horse."

http://www.ammo-oracle.com
- tatjana@ar15.com
tatjana
Team Member
Offline
Posts: 1356
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 3:08:47 PM EST
[Last Edit: 5/6/2004 6:30:34 PM EST by brouhaha]
Other notes and observations:

A. Unlike non-fragmenting experiments with Wolf and GP90, Dr. Brouhaha (Hee!) was heard to exclaim "For crying out loud!" when it became apparent how many fragments he was going to be forced to recover with forceps.

B. Dr. Tatjana (Hee!) exhibited clear signs of glee with the degree of fragmentation. Dr. Tatjana (Tee Hee!) partook of multiple frozen drinks while Dr. Brouhaha (Hee!) performed the extractions.

Note: Neither Dr. Tatjana nor Dr. Brouhaha are Doctors of anything, they have, however, stayed at Holiday Inn Expresses.



Figure A: Left to right: M193, M196, M855, M856, 100 grain


Figure B: "High" penetrating 100 grain in gel


Figure C: "Low" penetrating 100 grain in gel


Figure D: Profile closeup of "High" penetrating entry


Figure E: Profile closeup of "Low" penetrating entry


Figure F: Head on closeup of "High" penetrating entry


Figure G: Head on closeup of "Low" penetrating entry


Figure H: "Blooming" highlight view of "High" penetrating round


Figure I: "Blooming" highlight view of "Low" penetrating round


Figure J: Recovered fragments by depth for "Low" penetrating round


Figure K: Recovered fragments by depth for "Low" penetrating round (highlight)







Sectional view of wound cavity from 0 - 11" for "Low" penetrating round. Dime shown for scale. Note: Block width is 20cm.
"...no secret so close as that between rider and horse." http://www.ammo-oracle.com - tatjana@ar15.com
tatjana
Team Member
Offline
Posts: 1357
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 3:09:17 PM EST
More to follow...
"...no secret so close as that between rider and horse." http://www.ammo-oracle.com - tatjana@ar15.com
brouhaha
Team Member
Offline
Posts: 4714
Feedback: 100% (7)
Link To This Post
Posted: 12/10/2002 3:10:05 PM EST
[Last Edit: 5/7/2004 9:49:29 AM EST by brouhaha]
"And now the night is through and the storm is passed, and everything that could be shaken was shaken and all that remains was all I ever really had"
Zak-Smith
Offline
Posts: 16
Feedback: 100% (7)
Link To This Post
Posted: 12/10/2002 3:30:32 PM EST
Excellent! So, are these loaded to the "commercial" .223 pressure levels, or the higher 5.56 "military" levels? Can you tell us who manufacturs the bullet, and/or what the Ballistic Coefficient is? thanks -z
tatjana
Team Member
Offline
Posts: 1358
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 3:35:55 PM EST
[Last Edit: 5/7/2004 9:49:35 AM EST by brouhaha]

Originally Posted By Zak-Smith:
Excellent!

So, are these loaded to the "commercial" .223 pressure levels, or the higher 5.56 "military" levels?

Can you tell us who manufacturs the bullet, and/or what the Ballistic Coefficient is?

thanks
-z



I can't be too specific no. I can say that the BC is very high. In excess of .400
"...no secret so close as that between rider and horse." http://www.ammo-oracle.com - tatjana@ar15.com
Hoplite
Team Member
Offline
Posts: 1453
Feedback: 100% (160)
Link To This Post
Posted: 12/10/2002 3:40:48 PM EST
what is the OAL of the cartridge?
Blessed are the peacemakers, for they will be called sons of God. I'd rather be sorry for something I've done then for something that I didn't do.
tatjana
Team Member
Offline
Posts: 1359
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 3:51:31 PM EST
[Last Edit: 5/7/2004 9:49:54 AM EST by brouhaha]

Originally Posted By Hoplite:
what is the OAL of the cartridge?





Left: M193, Right: Early Prototype 100 grain Open Tip round.
"...no secret so close as that between rider and horse." http://www.ammo-oracle.com - tatjana@ar15.com
brouhaha
Team Member
Offline
Posts: 4716
Feedback: 100% (7)
Link To This Post
Posted: 12/10/2002 3:52:57 PM EST
[Last Edit: 5/6/2004 6:32:49 PM EST by brouhaha]

Originally Posted By Hoplite:
what is the OAL of the cartridge?




2.255"
"And now the night is through and the storm is passed, and everything that could be shaken was shaken and all that remains was all I ever really had"
sesat_ram
Offline
Posts: 588
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 3:53:54 PM EST
[Last Edit: 12/10/2002 3:56:42 PM EST by sesat_ram]
thanks b&t for all that work. time to order that 22-243 ar10 upper. What is the optimum twist for this round? What is the slowest twist that can stabilize it?
tatjana
Team Member
Offline
Posts: 1360
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 3:59:10 PM EST
[Last Edit: 5/7/2004 9:50:03 AM EST by brouhaha]

Originally Posted By sesat_ram:
thanks b&t for all that work.

time to order that 22-243 ar10 upper.

What is the optimum twist for this round? What is the slowest twist that can stabilize it?



I doubt it will stabilize below 1:7 very well. We will be doing long range tests and accuracy tests later.
"...no secret so close as that between rider and horse." http://www.ammo-oracle.com - tatjana@ar15.com
Sgt_Gold
Offline
Posts: 44
Feedback: 100% (14)
Link To This Post
Posted: 12/10/2002 4:21:05 PM EST
A 100 grain bullet in a cartridge that is the same oal as the M193 round has got to have serious velocity issues. Has anyone done any long range chrono work yet? If the M193\M855 round won't fragment well beyond 200 meters, what will this one do?
tatjana
Team Member
Offline
Posts: 1361
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 4:32:41 PM EST
[Last Edit: 5/7/2004 9:50:13 AM EST by brouhaha]

Originally Posted By Sgt_Gold:
A 100 grain bullet in a cartridge that is the same oal as the M193 round has got to have serious velocity issues. Has anyone done any long range chrono work yet? If the M193\M855 round won't fragment well beyond 200 meters, what will this one do?



The 100 muzzles at around 2450 but can go higher with some adjustments. It has a very high BC and is still fragmenting down to about 2100 fps. That's a LOT of reach. We'll post more details on reach in our next installment. Stay tuned!
"...no secret so close as that between rider and horse." http://www.ammo-oracle.com - tatjana@ar15.com
ProfGAB101
Team Member
Offline
Posts: 730
Feedback: 100% (2)
Link To This Post
Posted: 12/10/2002 4:33:58 PM EST
I take it from the pics and the listed items for testing that this round did not require any additional throating, unlike some of the other commercial offerings which have been noted to be set back in some barrels?
anything less than 800rnds wasn't worth getting the gun dirty. April 6, 2006 - I can wait.
brouhaha
Team Member
Offline
Posts: 4717
Feedback: 100% (7)
Link To This Post
Posted: 12/10/2002 4:40:09 PM EST
[Last Edit: 5/6/2004 6:33:09 PM EST by brouhaha]

Originally Posted By ProfGAB101:
I take it from the pics and the listed items for testing that this round did not require any additional throating, unlike some of the other commercial offerings which have been noted to be set back in some barrels?



No, nothing special required for these.

That's what makes them so nice!
"And now the night is through and the storm is passed, and everything that could be shaken was shaken and all that remains was all I ever really had"
tatjana
Team Member
Offline
Posts: 1363
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 4:49:47 PM EST
[Last Edit: 5/7/2004 9:50:23 AM EST by brouhaha]

Originally Posted By ProfGAB101:
I take it from the pics and the listed items for testing that this round did not require any additional throating, unlike some of the other commercial offerings which have been noted to be set back in some barrels?



I'm going to edit the experiment text to reflect that the rounds are magazine length more clearly.

But yes, no modifications required. Magazine length. No throating/etc. The only restriction is a tight (1:7) twist. Our test rounds (velocity and gel) were all shot from a single magazine without any reloading.
"...no secret so close as that between rider and horse." http://www.ammo-oracle.com - tatjana@ar15.com
ProfGAB101
Team Member
Offline
Posts: 731
Feedback: 100% (2)
Link To This Post
Posted: 12/10/2002 4:54:25 PM EST
Thanks for the prompt clarification. Someone will be set to make a small bundle should this cartridge combo be for sale to the public.
anything less than 800rnds wasn't worth getting the gun dirty. April 6, 2006 - I can wait.
KevinB
Team Member
Offline
Posts: 1600
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 5:01:48 PM EST
Tatjana and Brou, Glad to hear that everything worked well! Maybe Tat will get rid of her BM 1:9 and get a really barrel now :) -Kevin
Your Village called - they want their Idiot Back...
tatjana
Team Member
Offline
Posts: 1364
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 5:03:24 PM EST
[Last Edit: 5/7/2004 9:50:31 AM EST by brouhaha]

Originally Posted By CANADIAN_TACTICAL:
Tatjana and Brou,

Glad to hear that everything worked well!

Maybe Tat will get rid of her BM 1:9 and get a really barrel now :)


-Kevin



Depends on the results of the upcoming TAP 75, 77 SMK and 80 grain tests. :)
"...no secret so close as that between rider and horse." http://www.ammo-oracle.com - tatjana@ar15.com
KevinB
Team Member
Offline
Posts: 1601
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 5:28:56 PM EST
Tat, Just bugging you - looking forward to those tests. (a second note I have to learn how to spell/type - really barrel - come on Kevin - real barrel)
Your Village called - they want their Idiot Back...
Katana16j
Offline
Posts: 159
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 5:32:08 PM EST
Silly Question? Why are you guys rooting around manually extracting the fragments from the slices? I'm fairly sure that alcohol dissolves gelatin (or is that acetone, anyhow I know SOMETHING dissolves gelatin). why not put the sections in a shallow tray and then cover with a solvent, wait a little while and recover the fragments from the liquid.
tatjana
Team Member
Offline
Posts: 1365
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 5:39:40 PM EST
[Last Edit: 5/7/2004 9:50:40 AM EST by brouhaha]

Originally Posted By Katana16j:
Silly Question?

Why are you guys rooting around manually extracting the fragments from the slices?

I'm fairly sure that alcohol dissolves gelatin (or is that acetone, anyhow I know SOMETHING dissolves gelatin).

why not put the sections in a shallow tray and then cover with a solvent, wait a little while and recover the fragments from the liquid.



When you say "liquid" above, you mean the hypersticky and viscous liquid that gets all over everything before starting to mold and smell bad such that your friends and family ask "have you been playing in the graveyard late at night again...?" That liquid? :)

(Can you tell we tried this once?)
"...no secret so close as that between rider and horse." http://www.ammo-oracle.com - tatjana@ar15.com
voilsb
Team Member
Offline
Posts: 200
Feedback: 100% (4)
Link To This Post
Posted: 12/10/2002 6:45:53 PM EST
wow, that's some impressive fragmentation. I can't wait to see how it performs at longer ranges. I'm even more excited at the possibility that it'll become commercially available, so little ol' me can buy some. I'm gonna go over to TFL and post about this, and give 'em a link. Maybe we'll get some new membership, too.
Brian Voils "But whatever was to my profit I now consider loss for the sake of Christ" (Phil 3:7).
new-arguy
Team Member
Offline
Posts: 2934
Feedback: 100% (2)
Link To This Post
Posted: 12/10/2002 6:52:43 PM EST
[Last Edit: 12/10/2002 6:55:05 PM EST by new-arguy]
Hahahahaha, Brou and Tatj are stinky! Hahahaha! Awesome testing you two. Is there a snowballs chance in hell we'll see any of this ammo, or something similar available on the commercial market? Oh, and BTW, where are your credentials and lab notes and the bibliography? Are you qualified to be giving this info? I hope you're smirking, that was a joke! [:P]
[b]FDCC - 1*[/b] FL Defensive Carbine Club; www.fdcc.us/ [b]Go chrome or go home![/b]
tatjana
Team Member
Offline
Posts: 1366
Feedback: 0% (0)
Link To This Post
Posted: 12/10/2002 6:54:20 PM EST
[Last Edit: 5/7/2004 9:50:54 AM EST by brouhaha]

Originally Posted By new-arguy:
Hahahahaha, Brou and Tatj are stinky! Hahahaha! Awesome testing you two. Is there a snowballs chance in hell we'll see any of this ammo, or something similar available on the commercial market?



"I see plans within plans...."

;)
"...no secret so close as that between rider and horse." http://www.ammo-oracle.com - tatjana@ar15.com
brouhaha
Team Member
Offline
Posts: 4718
Feedback: 100% (7)
Link To This Post
Posted: 12/10/2002 6:55:34 PM EST
[Last Edit: 5/6/2004 6:33:33 PM EST by brouhaha]

Originally Posted By new-arguy:
Is there a snowballs chance in hell we'll see any of this ammo, or something similar available on the commercial market?



I guess that depends on how cold Hell is.

It's all up to the military and the manufacturer. So we have no clue.
"And now the night is through and the storm is passed, and everything that could be shaken was shaken and all that remains was all I ever really had"
  Previous Page
Page:  / 5