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.

  • 3361
    MEMBERS
  • 191292
    MESSAGES
  • 0
    POSTS TODAY

Discussions

Squad Support Weapon   Army Guns 20+mm

Started 17-Jun by stancrist; 22568 views.
nincomp

From: nincomp

11-Jul

EmericD said:

a rifle grenade with the same payload as a 40 mm LV grenade will still be heavier than a 40 mm LV grenade (because of the grenade tail)

Since a rifle grenade weighs more than a 40mm LV grenade, what is the breakeven where the number of rifle grenades equals the same number of 40mm LV grenades + underbarrel grenade launcher?  

I am easily confused.  Is the more pertinent argument that 40mm LV grenades have too little HE so the better option would be rifle grenades with their higher payloads?

Mr. T (MrT4)

From: Mr. T (MrT4)

12-Jul

Rifle grenades are much more limited in terms off effective range and dealing with armor and bunkers has been relegated to LAW like launchers instead of riflegrenades.

In reply toRe: msg 124
gatnerd

From: gatnerd

13-Jul

I think the issue with Rifle Grenades is one of accuracy. How accurate are they, and how many RG's will a rifleman ever fire to be able to get combat accurate with one?

In the initial (I'd argue, wiser) use of the 40x46, the US had a dedicated Grenadier, armed with a M79, and thats what he did. His job was accurate grenade delivery, and both his practice and combat employment was largely focused on building and improving that skill set.

Given the huge trajectory, low velocity, and shitty sights, these weapons require a serious amount of 'zen' feel for the weapon and range to be used accurately, which is possible with practice. 

I was talking to a Vietnam marine awhile back, and he describes their grenadier being in the zone, and just blowing a VC sniper out of a distant tree on his first shot. Meanwhile he tried firing the M79 later and couldnt hit the broadside of a barn because he didnt have that 'zen' feel for the trajectory. 

M79 Grenade Launcher

Loading and firing the M79 Grenade Launcher.The M79 grenade launcher was a single-shot, shoulder-fired, break-action grenade launcher. The U.S. Army M79 fir...

Without extensive practice via dedicated grenadier (or a sophisticated smart scope) I suspect most of these low velocity weapons, whether they be RG's or 40mms, will have similarly poor accuracy to this guy in Iraq, whose dropping rounds right into the street in front of him, missing an entire building sized target thats just across the street in the middle of the day. 

Combat Camera: Marines Enter Fallujah, Firing M-203 Grenade Launchers (2004)

Vootage of Marines firing M-203 grenade launchers from a building corner at a car across the street. Scenes include Marines entering the city and clearing ea...

schnuersi

From: schnuersi

13-Jul

gatnerd said:

I think the issue with Rifle Grenades is one of accuracy. How accurate are they, and how many RG's will a rifleman ever fire to be able to get combat accurate with one?

This also is an intresting question.
I think it not only depends on the ballistics (trajectory, accuracy) but also on payload. How close to you have to get to achieve effect.
During WW2 the German rifle grenade launcher was considered to be accurate and effective. From all acounts it has been a pretty popular weapon. The GL-attachment was concidered a general piece of equipment and every soldier was trained with it. Although it seems in practice usually a dedicated grenadier used it.
As a side not the sight was considered so useless that it was common practice to shoot the GL just by guessing and pointing. Which according to records was easily done with a "litte" practice.
The standard HE grenade had a diameter of 30 mm, weighted 0,288 kg, 30 g explosive payload and was launched ~65 m/s. Since the grenade is heavier compared to 40 mm LV but has a comparable explosive payload maybe the fragmentation was better giving a larger area of effect resulting in the accuracy being concidered acceptable or good?

gatnerd

From: gatnerd

13-Jul

schnuersi said:

As a side not the sight was considered so useless that it was common practice to shoot the GL just by guessing and pointing. Which according to records was easily done with a "litte" practice.

I've got a fair bit of experience with low velocity, high trajectory shooting. I used to build 'air cannons' for several years when I was a teenager, out of PVC pipe pressurized to 100psi. They could shoot a potato through a piece of 10mm plywood, and launch little PVC darts 500 yards. It helped that I lived directly next to a hardware store at the time.

Since the pressure was constant, and projectiles fairly uniform in weight, accuracy was surprisingly good - when in the 'zen' state of predicting high trajectory. I once hit a paint can on my first shot at 75yds standing - while holding over the can by several feet. I could just 'feel' that I was on target.

But when not in that zen state, accuracy could be wildly off base. Especially as distance increased.

I recall shooting at a bilboard sign down the street about 200yd that had an anti smoking PSA on it (was a fan of smoking as a teen.) A billboard is huge, but my elevation estimate was tremendously off. Ended up putting a potato through a guys open convertable roof who was driving by - I was 50 yards short and 50' low from my estimates. Needless to say that was the last attempt at that particular target.

Now a rifle grenade is going to be more accurate than a smooth bore potato launcher - but I suspect it would be a lot closer to a potato then a rifle bullet in terms of hit probability. 

I think any of these man portable HE launchers - whether they be 40x46, x51, rifle grenades, 60mm comando mortars, or RPG/Recoiless type launchers - really need some type of 'smart scope' to make maximum use of the limited number of rounds and small warheads. 

In reply toRe: msg 127
gatnerd

From: gatnerd

13-Jul

And some fun video of rifle grenades against a 'tank' target at what looks to be 40-50m:

Teaser: Dale shoots a tank with a Scary Flying Carrot of Doom (Swiss training rifle grenade)

A teaser for some upcoming content: our friend Dale demonstrates a fairly slick "Achtung Panzer" drill, switching a Swiss Sturmgewehr 57 from ball ammunition...

And a very nice history of Swiss Rifle Grenade history and doctrine. The use case seems to primarilly be emergency tank/vehicle defense within 50m, rather then 100-400m anti personell.

SWISS FLYING CARROTS: Stgw. 57 Rifle Grenades (Part 1/2: History)

Dale takes us through the historical background leading to the Swiss Sturmgewehr 57 rifle grenade series, starting from the WW2 and post-WW2 perspective. In ...

  • Edited 13 July 2022 10:19  by  gatnerd
schnuersi

From: schnuersi

13-Jul

gatnerd said:

I think any of these man portable HE launchers - whether they be 40x46, x51, rifle grenades, 60mm comando mortars, or RPG/Recoiless type launchers - really need some type of 'smart scope' to make maximum use of the limited number of rounds and small warheads.

We propably can assume that it is generally accepted that the effectiveness of any weapon increases with the sofistication of the aiming system.

How much is needed for a given weapon system to be concidered effective is another question.
The ladder sight of the HK 69, the GL used by the German Army, since the '70 is generally concidered to be usfull and adequate by the users. I can remember GraPi sniping sessions on the shooting range. Consitenly hitting a standard rifle target at 300 was absolutely doable. No zen, no voodoo just competent use of the sight.

gatnerd

From: gatnerd

13-Jul

schnuersi said:

Consitenly hitting a standard rifle target at 300 was absolutely doable. No zen, no voodoo just competent use of the sight

I'm sure that is the case at a target range.

Id question how repeatable that is against targets of an unknown, irregular distance, where the shooter has to eyeball the target distance and adjust the sight accordingly. Especially if the target involved is higher or lower then the shooter.

The Milkor sight is calibrated in 25m increments, which means that the shooter has to be able to eyeball judge distance within 25m to achieve a hit. That takes a very refined eye to judge distances that well.

schnuersi

From: schnuersi

14-Jul

gatnerd said:

Id question how repeatable that is against targets of an unknown, irregular distance, where the shooter has to eyeball the target distance and adjust the sight accordingly.

Range guessing is allways a propblem. Even for rifle and MG shooting.
The difference is the impact of a grenade is much easier to spot.

My point was that even ladder sights do work. If the squad leader has a range finder or is good at guessing he can give the information to the grenadier who sets his sight accordingly and puts the grenade on target.
The grenadier doesn'T need a sofisticated sight. He just needs range information.

gatnerd said:

Especially if the target involved is higher or lower then the shooter.

This also is a problem for all small arms. This can only be overcome with training.

This BTW is where rifle grenades shine. Training grenades are usually reusable. It only requires launching cartidges. So training is rather cheap, simple and safe.

gatnerd

From: gatnerd

14-Jul

schnuersi said:

Range guessing is allways a propblem. Even for rifle and MG shooting. The difference is the impact of a grenade is much easier to spot.

Sure, ranging is important for those weapons at longer distances. But the average rifle can hit a mansize target without any sight adjustment easily at 300m-400m. Hell, I can shoot my Glock against a mansized steel target at 100m with 7/10 accuracy. 

The trajectory of a 40x46mm grenade by comparison is so extreme that a hit against a building cannot be assured from 50m if the trajectory is off - this marine puts his first round right into the road in front of him instead of the building across the steet:

https://www.youtube.com/watch?v=hvEmOJSoJOk

At 200m, the 40x46mm needs 10m elevation over the target:

I believe Emeric had the exact specs in his GPC paper? Listing the allowable ranging error at various distances for 40mm to put the round within lethal frag range? I recall the allowable aiming error being shockingly tight. 

...

The average rifleman might carry 2-3 rifle grenades? That doesn't leave a lot of spares for correcting aim if the first shot is off.

  • Edited 14 July 2022 8:01  by  gatnerd
TOP