gatnerd

Military Guns and Ammunition

Hosted by gatnerd

This is intended for people interested in the subject of military guns and their ammunition, with emphasis on automatic weapons.

  • 3320
    MEMBERS
  • 188382
    MESSAGES
  • 1
    POSTS TODAY

Discussions

20x102 mm cannons   Army Guns 20+mm

Started 22/10/21 by Guardsman26; 6045 views.
roguetechie

From: roguetechie

23/10/21

The mk108 or something like the 108 is indeed interesting...

Or just something really cheap that can fire 30x113, that would work too.

gatnerd

From: gatnerd

23/10/21

Guardsman26 said:

Quite a few people have suggested that the fitting a 12.7x99 mm HMG on the UK's Boxer fleet is inadequate. Long-term, it seems likely that a turreted 30x173 mm cannon will be acquired. The question is, what will happen in the short-term?

Short term, I think probably the fastest, cheapest, and most bang for the buck option would be to retain the .50 RWS, and simply mount a coaxial missile system.

Either a Javelin, or the UK's new Martlet Missile, should be pretty straightforward to integrate (not sure what RWS the UK uses for Boxer.)

This 'CROWS-J' Javelin co-ax is what the US Army did to boost the firepower of many of its Strykers, as a response to basically the same set of circumstances presented here with the Boxer. Namely, we need to boost striking power over .50, but don't want to spend the money yet on giving them proper 30x173mm cannons. 

Given that the Boxer is essentially the UK's Stryker, its compelling precedent. 

And from a danger to the enemy standpoint, I think a .50+Javelin is likely more of a threat to enemy vehicles then a 20x102 or 30x113 cannon. (Of course a 30mm + Javelin + 7.62 gpmg would be the ideal.) 

https://www.dote.osd.mil/Portals/97/pub/reports/FY2018/army/2018strykercrowsj.pdf?ver=2019-08-21-155808-197

https://www.military.com/daily-news/2019/09/24/army-details-plan-equip-stryker-infantry-carriers-tank-killing-missiles.html

Beginning in 2022, the Army will start turning large numbers of Stryker infantry carriers into tank-killers by equipping them with remote weapons stations armed with Javelin anti-armor missiles.

The fielding of the Common Remotely Operated Weapons Station-Javelin (CROWS-J) is part of a larger effort to give the basic Stryker infantry carrier more firepower.

That effort began in March 2015, when commanders began requesting a 30mm cannon to give Strykers more punch than the standard .50 caliber machine guns if they have to face potential adversaries such as Russia.

The UK has apparently already tested this on a different vehicle (the Spartan) and found it very effective:

https://www.defensenews.com/digital-show-dailies/eurosatory/2016/06/15/javelin-missile-scores-100-percent-in-uk-vehicle-tests/

The British Army sponsored the tests fired from a Kongsberg M151 Remote Weapon Station mounted on a Spartan armored fighting vehicle in Salisbury Plain Training Area in Wiltshire, England.

Each Javelin flew distances between 1.2 and 4.3 kilometers and hit the ground target each time.

.........

"This is important within an expeditionary context where you take everything you need with you and don't get regular resupplies.."

...[Message truncated]
View Full Message
  • Edited 24 October 2021 2:25  by  gatnerd
gatnerd

From: gatnerd

24/10/21

roguetechie said:

The mk108 or something like the 108 is indeed interesting...

Yeah its very compact for an AC.

MK19 40x53 AGM: 78lbs, 43" long, 16" barrel 

MK108 30x90 AC: 128lbs, 41.6" long, 23" barrel 

M230LF 30x113 AC: 160lbs, 84" long, (?) barrel

...

In terms of warhead size, it also launches a 330g shell, which is nearly the payload of the 30x173mm. So for a HEDP Airburst or HE-Frag load it would outperform 30x113, albeit with less overall range / longer time of flight. 

I'm curious what the 30x90's powder charge is, and how it would compare in terms of recoil and blast to the 20x102 and 30x113.

stancrist

From: stancrist

24/10/21

gatnerd said:

This 'CROWS-J' Javelin co-ax is what the US Army did to boost the firepower of many of its Strykers...

A logical way to boost combat power.  Glad to see it happening. 

I proposed Javelin as IFV armament a quarter of a century ago.

See p. 24   Armor, September-October 1995 Edition (army.mil)

autogun

From: autogun

24/10/21

roguetechie said:

The mk108 or something like the 108 is indeed interesting... Or just something really cheap that can fire 30x113, that would work too.

An extract from my forthcoming Autocannon book might be of interest:

30MM MF: 30 × 113B AMMUNITION. The US company Suppor t Weapons Corp (SWC) announced in 1991 that it had developed the MF 30mm cannon, which fires standard ADEN/DEFA rounds and therefore uses electrical priming. It is recoil-operated, fires from a locked bolt and can operate in semi-automatic (closed bolt) and fully automatic (open bolt) modes, at firing rates up to 450rpm. Ammunition can be fed from a belt, a 10-round box or a gravity-feed system mounted on top of the gun. Peak recoil was stated to be similar to the .50 M2, achieved by an unspecified recoil-spreading system, and the gun was designed for use on standard .50 M2 and 40mm MK19 mountings. It was said to weigh less than 50kg and to be 170cm long. Successful firing trials were said to have taken place attached to an ultra- light aircraft.

The MF 30 will fire any ADEN/DEFA ammunition including the LW30 range developed for the M230. One interesting variation is that it was also designed to fire a specially-developed ‘mortar’ round in conjunction with an SWC ground mount which permitted firing at 45o. This round (in development at that time) was intended to contain just enough propellant to cycle the action, allowing a much longer and more destructive HE/Frag or HEDP shell to be fired.

gatnerd

From: gatnerd

24/10/21

That’s awesome Stan. You were very ahead of the times - proposing both Javelin plus 30x113mm. Both of which are now coming to fruition.
 

I wasn’t aware of the ASP; looks like a cool system / possibly the better gun then the M230lf:

https://guns.fandom.com/wiki/Boeing_ASP-30

  • Edited 24 October 2021 6:49  by  gatnerd
gatnerd

From: gatnerd

24/10/21

autogun said:

Peak recoil was stated to be similar to the .50 M2, achieved by an unspecified recoil-spreading system, and the gun was designed for use on standard .50 M2 and 40mm MK19 mountings. It was said to weigh less than 50kg and to be 170cm long. Successful firing trials were said to have taken place attached to an ultra- light aircraft. The MF 30 will fire any ADEN/DEFA ammunition including the LW30 range developed for the M230. One interesting variation is that it was also designed to fire a specially-developed ‘mortar’ round in conjunction with an SWC ground mount which permitted firing at 45o. This round (in development at that time) was intended to contain just enough propellant to cycle the action, allowing a much longer and more destructive HE/Frag or HEDP shell to be fired.

Very cool Tony.

Both that cannon and the ASP mention having recoil comparable to the M2 .50. Whereas when we see videos of the M230LF firing, its rocking vehicles on their shocks... shame these reduced recoil 30mm AC's didnt catch on.

That 30mm 'Mortar' round sounds super cool. Any idea of what the shell weight was? Was it larger then the 30x90's 330g shell? 

In terms of the MK108 cannon / 30x90 - do you happen to know how the recoil was for the MK108? Or what the powder charge was for the 30x90? 

In reply toRe: msg 18
gatnerd

From: gatnerd

24/10/21

In terms of the Javelin, the newest model, recently released, is the Javelin-F. 

https://www.defensenews.com/2020/05/06/deadlier-f-model-javelin-antitank-missile-rolls-into-production/

The F model has equal or better Anti-Tank ability then the previous Jav, while also adding a Blast Fragmentation sleeve to warhead, which reportedly doubles its effectiveness against infantry and soft targets. 

The US has ordered some 2k F models this year, and that is likely the one that would be loaded onto the new Strykers. 

As a firepower booster for Boxer/Stryker/other AFV's, its pretty awesome. It turns the poodle shooter .50 RWS into a viable tank buster, while also having serious effects against infantry or buildings. 

autogun

From: autogun

24/10/21

gatnerd said:

That 30mm 'Mortar' round sounds super cool. Any idea of what the shell weight was? Was it larger then the 30x90's 330g shell?  In terms of the MK108 cannon / 30x90 - do you happen to know how the recoil was for the MK108? Or what the powder charge was for the 30x90? 

I have no further info on the MF 30 ammo.

Recoil of the MK 108 is not easy to compare because of the recoil-smoothing effect of the API blowback mechanism.

In reply toRe: msg 20
Guardsman26

From: Guardsman26

24/10/21

Thanks for the responses. Going back to my original post, the US Army is adopting Northrop Grumman's new SkyViper 20x102 mm cannon. What's interesting about this is that it'll be dual-feed with new AP and HE ammunition natures. I also hear that they are looking at lightweight steel and polymer cases. In which case, Stan's observations about ammunition weight relative to 30x113 mm become otiose. The existing 20x102 mm APDS round already has superior penetration to 12.7x99 mm BMG. The existing point detonation HE round is also good. In other words, could ammunition development transform this calibre and make it relevant to today, not only for mounting in aircraft, but also for armoured vehicles to engage infantry, other light vehicles and aerial targets? 

The question is what would 20x102 mm give you that 30x113 mm cannot? I think there are three potential advantages:

1. Kinetic armour penetration versus chemical effect of new APDS with tungsten and depleted uranium options 

2. Better performance against aerial targets due to higher velocity and higher rate of fire (crucial for engaging drones / UAVs)

3. More ammunition carried for the same weight than 30x113 mm

The one advantage of 30x113 mm is its Proximity air burst ammunition. This has a lethal burst radius of around 3 metres. If it were possible to develop a 20x102 mm Prox round, I suspect the lethal burst radius would be 2 metres. This would not be as good, but might be enough to kill a drone, especially when fired in bursts of 5-10 rounds. 

If the collective view here is that 30x113 mm is superior, why is 20x102 mm being considered by the US Army?  in the FARA attack and reconnaissance helicopter and is choosing this calibre over 30x113 mm.  

TOP