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20mm Projectile
- Thread starter Fragman
- Start date
Chris 42 RQ
Well-Known Member
20 MM Vulcan Projectile.?
My money is on it being a 20 MM Vulcan projectile due to its profile and the fact that the Lot number is stamped into the driving band (an American practice especially on Vulcan projectiles) and although it is rather early production (1953) I think it may even be an early developement round due to the colour and method of securing the nose cap.
Although what "LP" stands for I have no idea.
My money is on it being a 20 MM Vulcan projectile due to its profile and the fact that the Lot number is stamped into the driving band (an American practice especially on Vulcan projectiles) and although it is rather early production (1953) I think it may even be an early developement round due to the colour and method of securing the nose cap.
Although what "LP" stands for I have no idea.
Thanks Chris, It was part of a belt I brought at a gun show several years back. The belt consisted of mostly empty casings, a start round and two with heads (one green and one yellow). I brought them with the intention of turning them into cutaways, but then realised when I got home that I new nothing about them (or how safe they were). I've come to the conclusion that I should stick to grenades, and have not touched them since. Cheers
Forgot to explain some more details on the round......
LPT stands for Low Pressure Test.
If it is a 20x110 USN round (depending on the length of the projectile) , it is used in the MK 11/ MK 12 aircraft gun as used in the A-4 Skyhawk.
Skyhawks are/were also used in the airforce of New Zealand.
Regards, Cornman
LPT stands for Low Pressure Test.
If it is a 20x110 USN round (depending on the length of the projectile) , it is used in the MK 11/ MK 12 aircraft gun as used in the A-4 Skyhawk.
Skyhawks are/were also used in the airforce of New Zealand.
Regards, Cornman
Tony Williams
Well-Known Member
The MK12 was installed in the Skyhawk (wing roots) but the MK11 was only ever available in a gunpod. Do you know if NZ had the gunpods?
Hi. Thanks for the information. I will post some better photos shortly; it's Saturday morning NZ time and if I wake me family up looking for them they might use them on me:sad:. As they came from an Auckland gun show it's highly likely they are from a Skyhawk. I have no idea whether or not we used gunpods.
I collect mainly grenades, so know very little about 20mm ammo (these were brought on a whim). What is a Low Pressure Test projectile (i.e. whats inside it and how was it used?) Thanks
I collect mainly grenades, so know very little about 20mm ammo (these were brought on a whim). What is a Low Pressure Test projectile (i.e. whats inside it and how was it used?) Thanks
hicky1300
Well-Known Member
Hi. Left hand one is a drill/dummy round.
Mainly used for training armourers in loading etc. Sometimes depending on aircraft load were used as ballast.
There are many variants of the vulcan drill rounds this should be a chromed copper/brass or steel hollow case with a steel insert (sometimes the base is turned steel threaded & bonded into body) this is to replicate the weight of a live round & to balance it.
Links are for the original M61 gun & belt system. the later M61A used the linkless feed system (same as on Apache).
Case on the right I think may be another drill case with the head removed?? Does it have any 1/8th inch holes in the case about 1/2 inch from base?
What are the projectiles above? 30mm?
Mainly used for training armourers in loading etc. Sometimes depending on aircraft load were used as ballast.
There are many variants of the vulcan drill rounds this should be a chromed copper/brass or steel hollow case with a steel insert (sometimes the base is turned steel threaded & bonded into body) this is to replicate the weight of a live round & to balance it.
Links are for the original M61 gun & belt system. the later M61A used the linkless feed system (same as on Apache).
Case on the right I think may be another drill case with the head removed?? Does it have any 1/8th inch holes in the case about 1/2 inch from base?
What are the projectiles above? 30mm?
Tony Williams
Well-Known Member
Judging by the apparent length of the cartridge cases and the projectiles, these do seem to be for the 20x110 USN. Can you confirm the exact length of both? (Measuring the projectiles from the bottom of the driving band - mine are firmly crimped in so I can't measure their total length).
Hi. From the tip of the green projectile to the bottom of the driving band is 73mm. The casing that is in the photo may not have been the one that came with the projectiles. I have a small section of belt somewhere with about 12 casing (I've got 3 young boys, so it could be anywhere). I'll have another look tomorrow. The casing has no primer, so may well be a drill round. The driving bands above the projectiles in the photo is just a close-up of the driving band.
I remember being told when I got them that the aluminium one is referred to as a starter and is used to load the belt in the gun without loading a live round. No idea whether this is BS or not.
What is a "Low Pressure Test" round used for and what does it contain? Cheers
I remember being told when I got them that the aluminium one is referred to as a starter and is used to load the belt in the gun without loading a live round. No idea whether this is BS or not.
What is a "Low Pressure Test" round used for and what does it contain? Cheers
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Tony Williams
Well-Known Member
Definitely 20x110 USN - the 20x102 measures about 5mm shorter.
The case looks like the right one for that projectile.
Hi Colin,
The LPT projectile /round was a factory pressure test function round to test the MK.12 cannon.There are a lot of these in NZ as they were fitted to cases and used as (inert) drill rounds until replaced by the locally produced solid Alloy dummies.
THE LPT projectile is inert loaded,essentially a TP projectile.
The alloy rounds are used as you describe,usually 3 at start and 3 at end of belt.
The MK.11 cannon pod was not used by NZ,just the standard fitted MK.12.
cheers Bob
The LPT projectile /round was a factory pressure test function round to test the MK.12 cannon.There are a lot of these in NZ as they were fitted to cases and used as (inert) drill rounds until replaced by the locally produced solid Alloy dummies.
THE LPT projectile is inert loaded,essentially a TP projectile.
The alloy rounds are used as you describe,usually 3 at start and 3 at end of belt.
The MK.11 cannon pod was not used by NZ,just the standard fitted MK.12.
cheers Bob
Examples of HPT and LPT and Dummies 20 x 110USN mk.100 .
The TP is for comparison.
Note the HPT has the older style m75 projectile,The HPT needing a slightly heavier projectile to increase pressure.
The 2 alloy rounds are local NZ produced, left one is the earlier pattern Right one is the later and more accurate detailed model.I've been told these where made because the earlier 2 piece (proj./case) rounds the projectiles where seperating dyuring function testing.
The FCT (firing circuit test) Cart. is just a case with elecric primer for testing firing circuit in the MK.12 cannon.
cheers Bob.
The TP is for comparison.
Note the HPT has the older style m75 projectile,The HPT needing a slightly heavier projectile to increase pressure.
The 2 alloy rounds are local NZ produced, left one is the earlier pattern Right one is the later and more accurate detailed model.I've been told these where made because the earlier 2 piece (proj./case) rounds the projectiles where seperating dyuring function testing.
The FCT (firing circuit test) Cart. is just a case with elecric primer for testing firing circuit in the MK.12 cannon.
cheers Bob.
