MG? Ranging/Target Board

[TEW]

Dear Forum,

I've had this wooden board for some time and worked out some of what it is, what it's for and how it's used but there are still a few missing bits of info. (A few maps I've worked on at bottom of post).

 

I've presumed it's for a Vickers MG as it refers to 'belts of ammo' but NB the reference to 'K Ammunition' which I can't find anything on for Allied Ordnance. Plus it says 'use battle sights up to 700 yds' whereas I have an artist's impression of a Vickers Crew using the sights for a target at 2500yds. (British Tommy 1914-18 Osprey). At night or in poor visibility all sights are surely useless? The emplacement is about 37 metres above the SOS target and at a range of 3000yds must be out of view, so the rounds must have to drop down into the ravine having lost velocity??

 

 

Some of the abbreviations are eluding me, although I think 'Q' relates to it's location in Map Sq Q as it's Gun No Q.15.7 Located at Q.15.a.45.15, but ;

SOS Target. I assume this means on an SOS being given open fire on the target.

QE 6° 25'. Is this Elevation of the gun?

Clearance over FT 83x. I came up with 'Clearance over Forward Trench', but 83x ? Where x seems to be used for Yards on the base scale.

RO 149° Mesnil Church. Right Observation sighting on Church Tower?

Other things I've noticed is that the board has been re-used, the angles on the protractor like arc bear no relation to the angles given for targets or sighting lines. Plus there is some overwriting.

Having scanned it at 1:1 and played with Coreldraw for hours the precise scale varies depending on which bit I measure, but e.g. the SOS Target line overshoots the ravine in Q.17.d by 2-300 yds.

I've also included a map of the SOS trajectory based on a 21/6/1918 map which coincidentally? has a pencil 'X' right on the target.

 

 

Although I know where it relates to I don't know the when or who. The 3 blue battle lines (3/5/18 map) seem to lie roughly on the German front at the height of the Spring Offensive 1918, possibly until June 1918. The board was brought back by my Grandfather of 62nd Div origins but I can't place them in this exact location at any time. His whereabouts for April – July 1918 are very vague and it may be that it has no link to him other than he 'obtained' it somehow.

Any other thoughts or observations gratefully received.

Thanks

TEW

Edited 13 November , 2019 by TEW
Image replacing

[TonyE]

There are a lot of unknows in this obviously, but you are correct that this is a range card for SOS fire when required. Literally "when the rocket goes up".

It is certainly for a Vickers gun as you surmise. The reference to "K" ammunition I believe applies to rounds made by Kynoch and headstamped with a "K". This is a common abreviation I have seen in various reports to identify a particular make of ammunition, e.g. KN, B, etc. Whilst the familiar use of the term "K" ammunition normally refers to German armour piercing rounds, I don't think that has anything to do with this use.

It may be that the Kynoch ammunition was known to be accurate or reliable and so they wanted to reserve it for specific targets rather than just barrage fire.

The reference to using battle sights to 700 yards is probably because this is the longest range that was visible from the position. Although the normal sights went up to 2,900 yards, normally for long range fire a clinometer would be used to set the gun. This is a device that was fitted to the gun with a specific angle set for a particular range and then the gun adjusted to that angle by means of a spirit level. Whilst I do not actually think the 6 degrees 25 minutes is a range setting, it just happens that this angle equates to a range of about 2,350 yards with Mark VII ammunition.

Beyond that I am afraid I am not much help.

Regards

TonyE

[HVD5677]

Very interesting piece. What are the dimensions ? Does the board to be a purpose built item, or something made on a field-expedient basis ?

[Gunner Bailey]

Little changes over time. I have one of these from the New Addington Home Guard showing ranges to known targets on the Addington Palace Golf course (which of course would have been defended to the last!). My one is drawn on a waterproof cloth, similar to oilcloth.

John

[pjjobson]

Well, from an Artillery point of view QE is Quadrant Elevation and RO would be Reference Object. I can supply fuller explanations of what they are if it would be of any assistance.

Phil

[pjjobson]

On second thoughts these are the explanations:

Quadrant Elevation The angle between the angle of the bore, when the gun is laid, and the horizontal.

Reference Object A Reference Object is used for Artillery Survey. It may be one of the following:

(i) A point to which a bearing has been determined.

(ii) A point to which the angle from the centre of arc or bearing of fire has been measured and recorded.

(iii) A point selected from which to measure angles to other points in a round of

angles.

(iv) Any point to which the bearing is known.

Hope this makes it a bit clearer.

Phil

[TonyE]

OK, thanks for that. It looks like I was wrong and that the QE figure is for a clinometer setting on the gun to set range. However, as the gun position was above the target this would have been taken into account so the range would be longer that the 2,350 yards I mentioned.

I could work it out exactly from the Vickers tables, but I have not had my dinner, so some-one else can do it!

Regards

TonyE

[HVD5677]

In practice how would a "Zero Line" be established ? Any ideas on from which reference point the angles to the Zero Line (170 degrees) and the Menil Church (149 degrees) would have been calculated ?

[Jack Sheldon]

Of course both sides used range cards and panoramic sketches. The following two posts show an elaborate German example captured near Ziel House (East of Bellewarde Lake and south of Frezenberg) on 1 August 1917 and showing the view from a pair of machine guns back towards Ypres. The range detail is hard to make out, but of interest is the fact that the most distant target area is at 2,800 metres.

Jack

[Mick D]

Modern day range cards are still made in either of these two ways, i.e. a sketch as in Jack's post or an aerial diagram, and plotted onto a piece of paper (the box of a 24hr ration pack has one printed on it).

Mick

[TEW]

Thanks, TonyE, Op-Ack, Vince , & Jack for the replies. Certainly answered some of my queries. I'll get back to you on the dimensions. I've assumed it to be made in the field as the scale/measurements seem to vary a bit depending on what you measure (unless board has distorted since made). The board does have an oil skin cover flap but nothing visible either side of it.

I assumed the Zero line and the arc of degrees to be a separate thing to the directions to Mesnil Church 149Deg and to 3^rd Battle line. 171Deg. The RO 149 to Mesnil Church cuts the outer arc at about 22Deg, so I thought board has been re-used. The heavy dark lines bear no relation to the arc lines. Well that's what I thought. Assuming that to be correct, the Correct Zero line for the darker lines would be at about 8 o Clock from the Gun position and based on either grid north or magnetic north

Regards

TEW

[TEW]

The board measures 257mm W x 195mm H. Or 10 Inches by 7¾ Inches. I assume it's based on a 1:10000 map but as I said, the scale seems to vary depending on what bit you take as a measuring point.

The version that should be visible in this post shows the orientation of the board based on the heavy dark lines to SOS target & Mesnil Church etc NOT the Degrees shown on the outer arc and marked 'Zero Line and Battle line' which I guess is for a previous location for the board. At the top where it says 'Gun No Q.15.7' there is something illegible written underneath. Ditto under Direction 99° 30'.

Still no clues as to 'Clearance over FT 83^x'?? Or as to when or by who this was being used?? I know my Grandfather went to 'Lewis Gun School' Le Touquet in May 1917 I wondered if they covered Vickers Guns as well in which case this maybe a training piece.

TEW

[pjjobson]

TEW

Regarding the Zero Line, this is from the Book Royal Artillery Glossary of Terms and Abbreviations:

Zero Line An imaginary line from a gun position, usually the 'centre of arc' to the expected target area. The guns were oriented relative to the zero line, which could be different for every battery. When the dial sights were set to zero and azimuth corrections to the guns were given as "more" or "less" degrees and minutes or mils. The layer would use the right hand to turn the right sight knob away for a "more" correction, and the left hand to turn the left sight knob towards him for a "less" correction. The Zero Line remained in use until 1956 when bearings were adopted.

[HVD5677]

The board measures 257mm W x 195mm H. Or 10 Inches by 7¾ Inches. I assume it's based on a 1:10000 map but as I said, the scale seems to vary depending on what bit you take as a measuring point.

The version that should be visible in this post shows the orientation of the board based on the heavy dark lines to SOS target & Mesnil Church etc NOT the Degrees shown on the outer arc and marked 'Zero Line and Battle line' which I guess is for a previous location for the board. At the top where it says 'Gun No Q.15.7' there is something illegible written underneath. Ditto under Direction 99° 30'.

Still no clues as to 'Clearance over FT 83^x'?? Or as to when or by who this was being used?? I know my Grandfather went to 'Lewis Gun School' Le Touquet in May 1917 I wondered if they covered Vickers Guns as well in which case this maybe a training piece.

TEW

Thanks Tony. This is really great. Is the oil cloth fastened to one of the edges, then folded under when board is in use and folded over otherwise

[Mk VII]

Still no clues as to 'Clearance over FT 83^x'

I'd guess this is for firing overhead of friendly troops, when certain safety angles have to be kept.

[TEW]

Thanks Op-ack & Mk VII,

The oil skin cover is simply tacked on the top edge and folds down over the board. It also has a picture hanger type thing but that may be for hanging as a decoration post war.

When I originally scanned it and played with Coreldraw the angles given to eg Mesnil Church do work out to be based on compass readings assuming my grid north arrow (previous post) to be correct the angle then measured by coreldraw (with magnetic difference does work out to 149Deg).

Regards

TEW

[HVD5677]

Thanks TEW.

[HVD5677]

TEW: One further question occurs to me....you originally said "oil skin" cover. I assumed this to be "oil cloth". Is the oil skin/oil cloth an opaque protective cover, or is more or less clear and designed to be written on ?

Thanks Op-ack & Mk VII,

The oil skin cover is simply tacked on the top edge and folds down over the board. It also has a picture hanger type thing but that may be for hanging as a decoration post war.

When I originally scanned it and played with Coreldraw the angles given to eg Mesnil Church do work out to be based on compass readings assuming my grid north arrow (previous post) to be correct the angle then measured by coreldraw (with magnetic difference does work out to 149Deg).

Regards

TEW