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 Fragment simulator cartridges for helmet test 
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Joined: Wed Sep 30, 2009 12:16 am
Posts: 292
Post Fragment simulator cartridges for helmet test
These cartridges have been handloaded at the Polígono de Experiencias de Carabanchel, the Spanish Army proving ground, for testing helmets from spanish manufacturers, according to Nato Stanag 2920.

Available primed cases are used (these are 7,62x51 SB 80).

The casemouth crimp applied to these specimens is too heavy, in my opinion, as the sabots are deformed. This would cause chambering problems.

The fragment simulator to be used with a sabot in 7,62 mm barrels is a simple steel cylinder with beveled tip, as seen in the photographs. The fragment simulator for 5,56 mm barrels has a driving band at the base, as it is intended for engaging the barrel rifling.

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Sat Oct 03, 2009 10:06 am
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Joined: Sat Sep 26, 2009 10:50 pm
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Location: The U.S.A.
Post Re: Fragment simulator cartridges for helmet test
Great pics. Let me display one more time my lack of ammunition knowledge by asking the following question. Why does one need to produce special ammo to simulate the schrapnel effect? Why could not one just use slightly underpowered AP ammo?


Sat Oct 03, 2009 11:30 am
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Joined: Thu Sep 17, 2009 1:13 pm
Posts: 204
Location: Prescott AZ
Post Re: Fragment simulator cartridges for helmet test
Believe these were also used in testing airplane canopy/windows and angle of impact isvery important in tests like these. I believe that is the reason for the odd shape of the projectile(s).
I have extra sets of these steel bullets (only) in 12.99mm, 7.88mm and 5.77mm (measured at the base). If anyone is interested please E-MAIL do not PM me for a price quote.

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Sat Oct 03, 2009 2:35 pm
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Joined: Wed Sep 30, 2009 12:16 am
Posts: 292
Post Re: Fragment simulator cartridges for helmet test
PetedeCoux wrote:
I have extra sets of these steel bullets (only) in 12.99mm, 7.88mm and 5.77mm


Is the 12,99 mm bullet intended for a 12,7 x 99 Browning barrel?

Can anyone provide a copy of Nato's Stanag 2920 so we can learn more on the subject?


Sat Oct 03, 2009 3:48 pm
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Joined: Wed Sep 30, 2009 12:16 am
Posts: 292
Post Re: Fragment simulator cartridges for helmet test
sksvlad wrote:
Why does one need to produce special ammo to simulate the schrapnel effect? Why could not one just use slightly underpowered AP ammo?


I think they try to duplicate the effects of an irregularly shaped piece of metal. AP bullets are designed to penetrate and this is not what they try to check (IMHO).

Furthermore, I don't think these steel projectiles fly very well. I guess they must hit the target sideways, base first or at random angles, unless fired from very close distances.


Sat Oct 03, 2009 3:51 pm
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Joined: Thu Sep 17, 2009 1:13 pm
Posts: 204
Location: Prescott AZ
Post Re: Fragment simulator cartridges for helmet test
[quote="schneider"[/quote] Is the 12,99 mm bullet intended for a 12,7 x 99 Browning barrel?[/quote]

I do not know for sure. The 5.77 mm driving band on this set only somewhat matches the 5.70mm shown on your chart. But it would seem to fit the pattern you list.

I see your 7.62 is a cylinder however the set I'm offering all have the 'driving bands' as you picture to the middle- right .

Your post is the first I've seen of a delivery system.
The proj. does not seem to fit the 'sabot' as closely as I would have thought needed, but perhaps the (over-size bored?) barrel is smoothbore? Being a steel proj. it would be quite hard on rifling to do a lot of testing while keeping costs reasonable?

Still I see you show a 5.56 fired projectile with rifling marks.

_________________
U.S.A.F. 1962 - 1966
IAA member since Jan. 1980
ECRA member since Jan. 1983
N.R.A. Life: April 1966, Endowment: March 1978
Keep your powder dry


Sat Oct 03, 2009 7:02 pm
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Joined: Wed Sep 30, 2009 12:16 am
Posts: 292
Post Re: Fragment simulator cartridges for helmet test
PetedeCoux wrote:
Being a steel proj. it would be quite hard on rifling to do a lot of testing while keeping costs reasonable?

Still I see you show a 5.56 fired projectile with rifling marks.


The "flange" or driving band is very thin and probably won't hurt the rifling too much, in my opinion. By the way, the fired projectile on my photo shows 8 grooves, so it was not fired in a Cetme L or LC 5,56 x 45 rifle (6 lands). Maybe they fire them in a special test barrel, just like they do to measure muzzle velocity and chamber pressure.


Sun Oct 04, 2009 8:27 am
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Joined: Mon Sep 28, 2009 10:11 am
Posts: 34
Post Re: Fragment simulator cartridges for helmet test
The flanged type was intended to be loaded to a case "as is," no sabot. There is an actual US DoD standard for fragmentation tests, the flanged projectile is for that. There is a .22, .30, and .50 caliber variant, probably bigger calibers as well.

The projectiles are manufactured and purchased by companies that have to meet that frag test standard. They then load the ammunition themselves, so it's not like LC or WCC or anyone is loading the ammo with those projectiles.

The appropriate material specification indicates which caliber fragment it has to withstand and at what velocity. The projectiles are then loaded accordingly.

These standards are separate from the "AP" MilSpecs that must be met, wherein the appropriate caliber AP bullet is used to do necessary certification testing.

Use of an AP projo in place of the fragment projo would violate the terms of the test. The milspec calls out the specific standards for the test and, if frag, calls out that specific projectile shape must be used.

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Sun Oct 04, 2009 9:50 pm
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Joined: Wed Sep 30, 2009 12:16 am
Posts: 292
Post Re: Fragment simulator cartridges for helmet test
Some more information about the fragment simulator projectiles used in Spain.

The flanged projectiles were the first ones in use. They were fired in a .22 Long Rifle commercial bolt action rifle (Zbrojovka Brno). The projectile was rammed into the barrel from behind, and then a .22 blank was loaded and fired. These blanks were cattle-killer loads from Santa Bárbara. They were medium power cartridges for calf killing.

It was found that this combination of steel projectile with flange plus cattle killer blank was too heavy for the rifle, causing malfunctions and parts breakages.

So they switched to the .22 caliber fragment simulator, unflanged, to be loaded into a sabot and fired in a special proof barrel caliber caliber 7,62 x 51 Nato. This permitted the variation of the powder charge in order to obtain the desired muzzle velocities.

Here are some pictures of the cattle killer blanks and their box. The year code used by the Palencia plant for commercial production started with the "A" in 1981, so this SB C was made in 1983.

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Sat Oct 17, 2009 2:37 pm
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