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25 X 155/RG GAU-7A CTA round

SG500

Well-Known Member
Premium Member
The GAU 7A was an American project worked on for about 5 years in the late 1960's in an attempt to produce caseless ammunition. During this time hundreds of different variations to projectile were tried.

The main contractors were General Electric and Philco Ford but many ammunition subcontractors were involved including Avco, Olin, General Motors, Hercules, Honywell, Aerojet and Brunswick.

The photographs show the Brunswick version.

This particular model is completely INERT and designed to be taken apart. The propellent is made out of wood and finished to look like the real thing.

If anyone has GAU 7A rounds in their collections in particular variations of the projectiles I'd be interested in seeing photographs of them.

Dave.
 

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Dave,

Excellent round! I've wanted one of these for years. Wasn't there also a 20mm version of the same design? They were being developed for use in the F-15 fighter when it was being designed in the 70s.
 
Dave,

Excellent round! I've wanted one of these for years. Wasn't there also a 20mm version of the same design? They were being developed for use in the F-15 fighter when it was being designed in the 70s.


Thanks John. Philco Ford did a similar design in 20mm but the case was metal. I'll do some reading up on it, I've got an excellent book about all this sort of stuff and let you know.
Dave.
 
I'm guessing the pictured 25MM projectile is/was a part of the above mentioned program. A little different nose cap, but wide plastic band and a very "aggressive" cannelure for attaching the caseless propellant. Got this some time back and don't recall the specifics, but this thread may be the answer to what this is. Sadly, the condition is not pristine and some of the lettering is destroyed, but maybe one of you can confirm this is part of the family.

OAL 117.4mm

Hi Rick yes yours if one of the many types of projectile they experimented with for the GAU 7 - they also fitted them to the GAU 8 when they tried necking it down to 25mm (why re invent the wheel after all!!) - I've shown one of those on a separate thread.
If you look closely at the third photograph that I posted you will see that the "aggressive" cannelure has a cardboard disc fitted into it which separates the lower charge from the upper one. The fourth photo shows the base of the projectile and the cardboard disc too.
Nice projectile.
Dave.
 
I have one of those projectiles in nice condition, in this pic of (mostly) experimental 23-25mm ammo:
23-25mm%20exp.jpg


The GAU-7/A was indeed intended for the F-15, but it ran into a couple of technical problems which caused its cancellation. The first was the fear that if the plane's magazine was hit, there was nothing to stop all of the ammo from going up in flames. So they introduced fireproof sheaths around each round, which had to be stripped off before loading - a real pain. The other problem proved insurmountable; the propellant was too exposed to climatic variations, caused erratic performance.
 
The GAU 7A was an American project worked on for about 5 years in the late 1960's in an attempt to produce caseless ammunition. During this time hundreds of different variations to projectile were tried.

The main contractors were General Electric and Philco Ford but many ammunition subcontractors were involved including Avco, Olin, General Motors, Hercules, Honywell, Aerojet and Brunswick.

The photographs show the Brunswick version.

This particular model is completely INERT and designed to be taken apart. The propellent is made out of wood and finished to look like the real thing.

If anyone has GAU 7A rounds in their collections in particular variations of the projectiles I'd be interested in seeing photographs of them.

Dave.

This is the only one I've got, but its a sad photo - I think its the only photo of this item I've got with me.

I think I photographed some of these in an EOD collection some years back, I'll dig tonight and see what I can find.
 

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Sorry about this, I dug out the photos and on closer inspection I'm pretty sure that they are from a different program. Which program(s) I have no idea. Here they are regardless.
 

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This is the only one I've got, but its a sad photo - I think its the only photo of this item I've got with me.

I think I photographed some of these in an EOD collection some years back, I'll dig tonight and see what I can find.

Yes that's the brunswick 25mm, nice sectioned specimen you have.
Thanks for showing it.
Dave.
 
Sorry about this, I dug out the photos and on closer inspection I'm pretty sure that they are from a different program. Which program(s) I have no idea. Here they are regardless.

OH YES there's some very very nice rounds there, if only they were over here in Wales safely in my collection. They really did do a hell of a lot of work trying to get them to work.

Attached are a few of the links I can find on the forum to similar things, some are similar or the same as some in your photos. Have to say I have a bit of a liking for these unusual rounds.

Thanks for showing them.

45x305 Ford aerospace APFSDS round

http://www.bocn.co.uk/vbforum/45-x-305-t50153.html?t=50153


Nutcracker rounds

http://www.bocn.co.uk/vbforum/very-rare-nutcrackers-t40828.html?t=40828

Hughes lockless

http://www.bocn.co.uk/vbforum/hughes-lockless-cta-t31187.html?t=31187

25 x 145

http://www.bocn.co.uk/vbforum/25x145-rounds-plus-t22880.html?t=22880

30mm AMCAWS

http://www.bocn.co.uk/vbforum/30-x-165-t30897.html?t=30897

25X152 Philco Ford

http://www.bocn.co.uk/vbforum/30-x-165-t30897.html?t=30897

Various CTA rounds

http://www.bocn.co.uk/vbforum/cta-rounds-t55569.html?t=55569
 
This is a photo I took from the storage area at the Air Force Armament Museum, located just outside of Eglin AFB in Florida. It is an experimental cartridge for an aircraft gun, is it related to this program?
 

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Jeff,

I have something that looks similar, but a little larger in diameter. It has a rocket inside, that is pre-rifled on a copper rotating band, and has 2 nozzels canted to cause spin. The primer screws in to the closed end of the tube, to hold the rocket in the container, and the boom evidently breaks upon firing. The launch tube looks to be stainless and is a little larger in diameter on both ends, just like the photo you posted.
 
This one has a fin-stabilised flechette package, I'll try to post it tomorrow if I can. I'm in a hotel in Italy right now, I've had better internet in Ethiopia.
 
This is a photo I took from the storage area at the Air Force Armament Museum, located just outside of Eglin AFB in Florida. It is an experimental cartridge for an aircraft gun, is it related to this program?

Interesting round!
The only thing I have listed that is in that sort of size range is a 45x270/RG COMVAT CTA round (head diameter 67mm) but that's a tank round and by the look of the round in your photo that would be too short - the one in the photo looks more like 290mm.
Dave.
 
No idea. The museum tag in storage only identified it as an experimental aircraft flechette cartridge.

I'll use the photos to ressurect my flechette thread, just for Peteblight
 
Markings on Brunswick rounds

Just had a few queries about the attached.
I thought they were exactly the same until I compared them.
What does SV stand for on the one band?
Also how were these fed into the gun. It may sound like a really dull question but I hadn't thought about it before. Were they belt fed or fed on some other linkless feed?
BOTH are INERT models made to represent the real thing.
Dave.
 

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Sorry for the necrobump. I registered after finding this thread while doing some searching. My family owns the land that contains what's left of the abandoned Brunswick ordinance facility that developed & produced this round. It was constructed on farmland and has been since turned back into one, so many of the buildings have been gutted for hay & equipment storage. Still, some have not and even some of the original equipment & documentation remains, including the forward & aft charge press lines & the test fire range. I even found the original phase IV technical proposal.

The 25mm GAU-7/A round was but one of many projects they were into at that time, including grenade fuses, illumination flares & lots of various CS gas ordinance & delivery systems. They continued using the facility up until the mid 90's for mostly storage and some various aircraft & mobile shelter parts plating, but the bulk of the activity pretty much came & went with Vietnam. It was sold off once the other three local Brunswick plants were swallowed up into General Dynamics in the late 90's. The place was a big deal back in the day, and many folks were killed over there.

I'll check back in and post a bunch of pictures if you guys so desire.
 
Hi crunchysuperman and welcome to BOCN. Thanks for registering and yes please if you could post some photos it would be great. Finding specimens like this is the easy bit, finding out the information/documentation about them and the development programmes is even harder. Photos of the site and what's left of any of the facilities there now would be a bonus.
Dave.
 
Test fire fixture where the gun was mounted. The "funnel" housing you see a few feet outside the building is made of concrete 2 feet thick. The plate at the end with the hole is a solid steel plate 3 inches thick. All of this was presumably to contain errant shots. I have more shots of this building somewhere - I'll post when I upload them. Anyway, about 300 yards downrange is a hillside with the remains of target bases made from I-beams. One of the earlier complex schematics I have shows a "projectile recovery building" next to the target area, but that must have been torn down ages ago, as we can find no evidence of it.

There is a large sliding door covering this opening to the room, rolled open in this shot Also, this building houses a mirror image test room & fixture next to this one, right down to the concrete "funnel". Again, this is shown better from an outside shot, which I'll have to dig up.
IMG_1219-50.JPG
 
Thanks for the photos, brilliant! WOW! Imagine having your own private test facility to explore! Dave.
 
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