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3.7 AA projectile


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Premium Member
Hi has anybody got any pic's and measurements of a 3.7 Mk1-111 projectile as i have a Mk1 case and would like to make a dummy head up until i can afford one that is:xd:
3.7AA Projectile

Hi Andy
Here is a photo of a 3.7 AP projectile if you are after some other type please let me know & i'll dig out my other rounds.


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Thanks Harry, i wanted the AA HE round if you have it as i just need the length without fuse and the measurements of the driving band.
3.7" projectile

Hi Andy
Here is a photo of the HE & practice flash.
The dimensions are visible projectile with fuse 407.3mm without fuse 301.8
The ogive starts at 160.3 from the bottom of drive band.
Drive band is 35mm deep & 96.6 in diameter.
Do you need the details on the grooves in the band?
All the best for now


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Harry, what type of fuzes are they in the photo? I always thought the 3.7" used the No. 199 Fuze, but they are clearly different from the No. 199.

I would like to find a complete inert 3.7" AA Round or even a case, but I can't find one anywhere. How much would a case cost? I imagine that a complete round ( case, primer, proj, fuze) would be into triple figures.

The British cases above 18 or 25 Pounder from both wars seem to be very hard to find. I would also like examples of the 4", 4.5" and 4.7" Naval cases, but also, can't find them anywhere, not even the modern 4.5" cases.
3.7" projectile

Hi Andy & Weasel

Thanks for your comments on the rounds..

Not a problem Andy if you need any more information just let me know.

Hi Falcon
The fuse in the 3.7" are No208, the 3.7" could be fitted with No117, 199, 207, 208, 209, 223 & some later ones like the L1 & L7.
You sometime see 3.7" cases up for sale I may have a spare in my garage, but I've not seen a complete round for sale for sometime, couldn't tell you how much a case would cost I traded for most of my rounds the 2 I did buy the original marked up HE & the APCBC where both in triple figures.
There are a couple of 3.7" cases on the auction at the moment one at 40.00 & one at 25.00
The 4" is much the same as the 3.7" you do see cases now & again for sale, but projectile & complete rounds I've not seen for sale for sometime ether, I always find navy bits are hard to find, I don't know if it because they throw the case over board after firing or not. The modern 4.5" case which one is it you are after?
If you have a spare 3.7" Case I would definitely be interested.

I know what you say about Navy bits. On the HMS Belfast, there is a primer for the BL 6" separately loading gun used as a handle on one of the latches on the door to one of the forward turrets. I have never seen one of these anywhere else, let alone seen one for sale. It is also another bit I would like.

There are also racks full of complete inert 4" Rounds out in the open air to rust!!

I'm didn't even know that there were different modern 4.5" cases. I'd like any one, but the trouble is storage space for those huge cases.

Do you know what the biggest brass cartridge case ever manufactured in the UK was? I heard there was a 6" Gun that used a case, now that would be a nice find.

The biggest calibe British case I have reference to is a 133 x 778R for the 5.25" AA Guns Mark 1, 2 and 3. I know Germany made some really big stuff that took cases (a fair few over 300mm, up to 863 x 1300R for the WW2 Dora 80cm Railway Gun).

Hi Falcon, i have a 4in Navel case spare but no primer for it, i am open to offers.


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Hi Falcon, i would have thought about 35.00 i will get a price for p&p if you are interested
Hi Falcon
I've attached a photo of the 3.7" case & the 4.5" case I have spare if they are of any
interest to you.
There is also a photo of 3 case type I have left to right Mk3-5, Mk2 & Mk8 for the 4.5"
As far as know the 6" is the biggest British cased round but some one may know better, the 6" is 163 x 1181R.


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Nice items

Hi Harry G very nice items !

Is the first round (practice) screwed into the case mouth !

Chris :tinysmile_shy_t:
Thanks for the photos. I would have to collect them in person next time we meet as posting obviously is not practical or cost effective. Does the 4.5" Case have holes in it?

That 6" Round is a superb item. Is it in your collection? I take it that it is something you would never find again. Would a picture of the headstamp be possible? What period is it? I presume that it's a naval round. would the gun that fired it been classed as a "QF" gun, as the case is a fixed round? Which ships carried it? Perhaps we should start another thread on this.
Original paint 3.7in AA practice flash. Projetile is dated 1950. Anybody got a post war case to swap?

3.7in AA HE projectile, open to offers on this one.



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Quatermass: If I bought a 3.7" case off someone, I would be interested in your Proj, the dates don't have to match or anything, i just think it would make a nice display item with a case.
3.7" projectile

Hi Chirs
Sorry for the delay in getting back to you & thanks for your comment, the projectile is originally a Proof of Fuse but for some reason the band & some of the stencilling has been over painted.
The projectile doesn't screw in to the case there is ether a Bakelite or white metal closure plug, I've attached a photo of the two of them for you.


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3.7" projectile

Hi Falcon
Sorry for the delay in getting back to you, not a problem over the cases if you are wanting them I can whole on to them & bring them down to Martins or if I'm down that way I could drop them off for you.
Yes there are two hole in the 4.5" case both have been sellotaped over.
The 6" is in my collection I have one case & 2 projectile I've been looking for another case for some time now, thought my luck was in when I seen Waffs photos of the war & peace show at Beltring as there looked like on in the middle of a photo but Waff said it had been sold.
The 6" is 1958 dated yes it is a navy round for the QF mk 5 gun, it isn't a fixed round the case is sealed with a white metal alloy cap much the same as the 4.5 Mk3-5 ( there is a photo of the 4.5 cap in the note to Chris ), I've attached a photo of the headstamp.
I don't know which ships they where used on HMS Belfast had 6" guns but don't know if they are QF or BL


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3.7" projectile

Hi Quatermass
Sorry for the delay here is the photo of the 3.7" APCBC roundIf you need any
dimension please let me know


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