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CTA question

MINENAZ16

Well-Known Member
Ordnance approved
Hello,
I'm lost with diameter of cased telescoped ammunition.

cta-40mm-ammo.jpg40_mm_CTWS_Telescoped_ammunition.jpg



These rounds are called 40mm CTA.
40mm si the diameter of the case or the diameter of the shell ?
Regards
 
I have a query regarding the painted bands on the cases.

Most have a brown ring. What does that signify?

Above that band is a black band for APFSDS, yellow for GPR-AB (General purpose round air burst) and GPR - PD (General purpose round point detonating), and blue for practice

..........or so I thought

As you can see from the photos that is not always the case. Why have a yellow band on one that is clearly marked "TP"?

Dave.

IMG_1774.jpgIMG_1775.jpg
 
I have a query regarding the painted bands on the cases.

Most have a brown ring. What does that signify?

Above that band is a black band for APFSDS, yellow for GPR-AB (General purpose round air burst) and GPR - PD (General purpose round point detonating), and blue for practice

..........or so I thought

As you can see from the photos that is not always the case. Why have a yellow band on one that is clearly marked "TP"?

Dave.

View attachment 178495View attachment 178496

Sorry Dave, I have no idea.

I lost my contacts in BAE some years ago.
 
The brown ring denotes 'Low Explosive Hazard' and this would be in reference to the cartridge propellant.

The second ring denotes the nature/hazard of the projectile.

Remember Practice means Practice and all that it entails, it doesn't infer the item is inert. The RAF have/used to have practice bombs that contained a very healthy GP spotting charge.

Whilst the markings on your round suggest it is a Target Practice - Tracer, it is quite possible that it has a flash/spotting charge, which is deemed to be of HE nature and would warrant a yellow filling band. There was a 120mm Practice HESH so filled.

The markings on your round appear fictious - "BB - MM/CC - AAAAAA" "Case Y-MM ? XXXXX"


IMG_1550.jpg
This is the forward section/warhead from a Swingfire Anti-Tank Guided Missile. As you can see there is an abundance of light blue paint and it's marked '"PRAC" all denoting Practice. However, it's also got a very large yellow filling ring denoting HE. Nothwitstanding they're guided missiles, some develop a mind of their own and turn back on themselves, or fly out of the safety area. To deal with such eventualities they are fitted with a "CBU" - Command Break-Up Unit, which is an HE charge, which can be fired by the fire team. When detonated, the charge destroys the front of the missile and motor, rendering it un-aerodynamic resulting in it crashing.

TimG

P.S. I note that the HE projectiles have a full body colour of yellow as opposed to full body colour of green with yellow filling rings.
 
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Thanks Tim that's a really useful explanation. As for the markings, who knows. Its an empty case that has clearly been left outside or in damp conditions as there's rust on it that are partly obscuring some of the markings so I assume markings are original. Can post more pictures if needed.

Dave.
 
To deal with such eventualities they are fitted with a "CBU" - Command Break-Up Unit, which is an HE charge, which can be fired by the fire team. When detonated, the charge destroys the front of the missile and motor, rendering it un-aerodynamic resulting in it crashing.

TimG

Our designation is/was FTS - Flight Termination System. Anything that had the capacity to make it off the impact area (WSMR) was fitted with one, often unique to the system, though sometimes from recycled components like an AIM-9 CROW warhead.
 
I would say your round was made for display rather than practice. It was not uncommon in the US at least to use x's in place of actual lot numbers etc, thereby showing the correct marking while not using a number that might cause confusion if the item were mixed up with live items.
 
Dave,

More photo's of your round would be most welcome.

TimG

Hi Tim some better ones of the markings on either side of the case.

Dave.
 

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