Mauser M03 - Rifle Box

Update - the completed rifle box can be seen in the background of this barrel change video.

I've built a box for my Mauser M03 rifles. My design criteria were that it needs to

- carry three rifles, with barrel and scope fitted
- hold the rifles so they're ready to use, with the bolt open and drawn back
- fit sideways across the rear of my Landcruiser and also on the back seat
- cushion the rifles during rough off-road driving
- protect the rifles and scopes from rubbing against abrasive high density foam
- fit under the rear cargo shelf when it's installed
- have a lid that's virtually airtight and that comes completely off
- be long enough to hold an M03 with a magnum or Africa barrel
- be high enough to allow a tactical scope with big turrets to 'float' in free air
- be strong enough but also light enough
- look good enough if any of my friends see it
- keep my rifles out of sight and secure during transit

My home-made Mauser M03 box is made with good quality 9mm plywood. There was hardly anything left from a 2440 x 1220mm sheet, meaning it would have been very heavy if I'd used 12mm ply.

Here's some pictures taken during construction.



I used 25mm high density foam for padding.

Photo's below show the padding on top of the dividing panels, to avoid bumps when lifting and replacing the rifles in the dark. I spent half a day on my knees reducing almost a full sheet of foam to pieces, sculpted to line every surface of the box.

The first trial fit of a Mauser M03 with a Kahles K624i scope put a smile on my face. This amount of clearance is just what I was looking for. The bolt is open and back. The scope's turrets are free floating. And there's room for an S&B PM II, one day.

Once all the pieces were cut my son and I spent a couple of hours gluing them into place with contact adhesive. The spray can ran dry just as we glued the foam on top of the dividers into place, so for the moment the bottom pieces are simply pushed in. They're a tight fit.

While we were glueing, my wife was sewing, to make up a piece of satin wide enough to drape through each compartment. This is the first trial fit. Great colour!

And now with some Mauser M03s added. :-)

The jpeg artefacts in this picture are crazy, but it does show that the rifles are snug, protected and ready for quick action. Just what I was looking for.

Next, we'll trim the edge of the satin a little and sew a casing for a shock cord and toggle. When the lid is off the satin will drape over the sides of the box by about 150mm, held in place with the shock cord. Before putting the lid back on the satin will be draped loosely over the top of the rifles. The inside of the lid will be lined with 25mm foam.

I'm happy to provide construction tips if anyone wants to build a similar box. :-)

MSR Reticle in Kahles K624i

Taking decent photos through a high power rifle scope is insanely difficult. Finnaccuracy have posted some taken through Kahles and Schmidt & Bender scopes and my hat goes off to them for how well done they are. The link goes to the S&B page - scroll down to see the reticle pics. There's more pictures on the MSR-Kahles page.

Here's a series of photos I took yesterday. The clarity is not very good, but they do show the reticle illumination. The features of the MSR reticle can also be seen.

Please keep in mind that the real view through the real scope is vastly better than photographed here. This reticle through this scope is simply a joy to use. :-) I was seeing individual strands of spider web on the rooftop air-conditioner, glistening in the sun, this morning.

The roof top is 230 meters away. The scope is set on 8x magnification for the photos below. The camera lens is picking up only part of the view through the scope.

This first picture is complete rubbish but sets the scene for the photos below.

MSR Reticle in Kahles K624i

After having so much trouble with the first shot I took the scope off the rifle (thank you Double Square Mount!) and set everything up again. This is a bit more useful.

MSR Reticle in Kahles K624i

The next shot shows the reticle illumination turned up high. It's very glary outside, but against a neutral background the illumination is very effective. The highest setting causes the illumination to look thicker than the black crosshair, which is useful at low magnification. 

MSR Reticle in Kahles K624i

And next, I've turned the illumination down. The central dot is just becoming distinct.
As mentioned in the previous post - measuring distances is a snap if an object of known size is present in the scene. The width of a house brick is 230mm; if it subtends 1 milliradian then 230mm ÷ 1 mil = 230 meters. A roof tile on the next house is 295mm wide. It subtends 1.2 milliradian. The distance is 295mm ÷ 1.2 mil = 245 meters.

MSR Reticle in Kahles K624i

Next, the illumination is turned down further. The red line is now close in thickness to the black cross hair lines. I'm going to keep trying to get better photos through the scopes. I think it's a matter of finding the right distance and focal length. My kids will probably hold their phones up and get perfect shots first time. :-)

MSR Reticle in Kahles K624i

Here is the reticle diagram for the Kahles K624i. I believe Kahles refer to this as their Gen II version. Click the photo to see more detail. Note that the subtension of the fine cross hair is 0.4 cm @ 100m, which is in-between the measurements for the MSR reticle used by S&B and Steiner (0.5 cm @ 100m) and the P4L-Fine used by S&B in their PM II scopes (0.35 cm @ 100m).

Kahles K624i on Mauser M03

Here are some pictures showing how a Kahles K624i riflescope looks mounted onto a Mauser M03. I think this scope is the least 'military' looking of those with similar features and utility. It's a good match for an M03. Further down I list some of the scope's features that make it a great choice.

Something to think about when mounting a tactical style rifle scope is the height of the rings and how far below the tube the turret housing protrudes.

 Like many tactical scopes, the Kahles K624i has a 34mm tube. Mauser can supply 34mm steel rings to go with the Double Square Mount; their height, from the base to the tube, is 12mm. The rings shown in these photos are from the Blaser R93 saddle mount system and are made from aluminium (hence the dings and scratches). Their height, from base to tube, is 7mm. The turret of the K624i protrudes 5mm below the tube, leaving 2mm clearance, shown in the photo below.

Features of the Kahles K624i that make it good choice are:

 - availability of the Multipurpose Sniper Reticle, by Finnaccuracy. Kahles have made some slight modifications to the MSR reticle compared with the standard version used by Schmidt & Bender and Steiner. The Khales version has slightly finer crosshairs and an open centre with a dot at the intersection. It is a thing of beauty. I'll post a photo once I've got a good one.

- the turret boss is big and the dials are wide, but not tall. The overall effect is that it's compact, compared with others. Have a look at the Steiner 5-25x56, or any Hensoldt! The photo below shows a K624i next to an S&B PMII. It may be that the large diameter turret boss makes more space for the click detents, which might explain how smooth and distinct the clicks are.



- the turret housing does not protrude too far below the tube - only 5mm. The housing of an S&B PMII protrudes a couple of millimetres more, which can create mounting problems.

- the controls are all co-located on the turret housing. The parallax/focussing control can be adjusted with either hand.

- the parallax/focussing control has gentle detents at the major distances - handy, especially in the dark.

- there is no tunnel effect when moving down to the lowest magnification - 6x. This video shows the tunnel effect with an S&B PMII 5-25x56 scope - not a fault, just a feature that S&B fans know about and don't really mind.



- there's a good length of tube fore and aft of the turret housing for mounting flexibility. However, a limitation will still be the separation of the rings on the rifle's mount - a 69mm opening with Mauser rings on the Double Square Mount, as well as for the Blaser R93 rings. Even with significantly longer tubes, the K624i is only slightly more flexible to mount than an S&B PMII 5-25x56, which has short tube lengths. The wide turret housing of the Kahles is the culprit. Mauser make a rail version of the Double Square Mount, an option if the fixed position of the integral rings is a problem. The rail is 103mm long (red arrows) and sits 21.5mm above the receiver (blue arrows).

- the illumination system is excellent. Only the central 1 milliradian crosshair is lit. It goes from very dim for moonless nights to very bright for daylight. There's a gentle detent for the off position. If the magnification is zoomed right down so that the reticle is very fine, the small brightly lit central cross is like a red dot. The control dial is a rheostat, for continuous and click free, pause free adjustment. I'm not too keen on the coin slot for the battery cover - similar to those found on Swarovski Z6i - it could be damaged when loosening and tightening.

- the optics are excellent. The eye box is trickier to use at 24x magnification than with a lower power general hunting scope, but that comes with the territory. It's better than other high power scopes I've used. The clear view with the MSR reticle is a thing to behold. Measuring distances is a snap if an object of known size is out there. Length of a house brick is 230mm; if it subtends 1 milliradian then 230mm / 1 mil = 230 meters. A roof tile on the next house is 295mm wide. It subtends 1.2 milliradian. The distance is 295mm / 1.2 mil = 245 meters.

The last two photos show how the red rotation indicator lifts when the elevation turret is turned into the second rotation. The turret takes a little more effort to turn when the mechanism begins to lift the indicator, but this is only noticeable if turning very slowly, click by click. The turrets on the K624i are really nice to use. The clicks are distinct, yet easy to control.

Please post a comment if you have any questions.

 

Mauser M03 Expert - it's got the lot!

Here's Mauser's new video on their entry into the 'Best Hamburger With The Lot' competition - the Mauser M03 Expert. For many Mauser fans this will be the ideal setup for stalking or running game. It comes with a solid profile barrel, which means Africa barrels can drop straight in to the stock - no need for adjusting the barrel channel. Same goes for Match barrels.

It's got me thinking. A synthetic one would be perfect for the rough forest hunting that will be adding character to my nice wood stocks. :-) Hmmm.

Reticles - First Focal Plane vs Second Focal Plane

"Why on earth would I want the reticle to get thicker when I zoom in?"

I had that thought more than thirty years ago when I read about the funny riflescopes that a little company called Schmidt & Bender was making in Germany. Apparently their scopes were really good. Apparently, having a zooming obelisk for a reticle was normal there. What I was clear about was that their scopes were eye blinkingly expensive. It all sounded like a disease, but it did make me curious. "There's got to be something in this," thought the penniless student. However, I had no option but to archive the thought.

When the archive was opened in mid 2012 I found that the rest of the world was paying more attention to European scope designers. More scopes were being offered with reticles in the first focal plane. Reticles that grow! Here's how that works.

Light from the sun or another source falls onto a scene in front of us and hits objects which absorb some of it. The rest reflects off in all directions. Objects that have absorbed hardly any of the light appear white to our eyes. Their colour is a mix of nearly all the light in the visible spectrum. Objects that are black have absorbed most of the light in the visible spectrum.

Imagine an object that is tiny; as small as the eye can see. A spec of pollen sitting on the surface of a large oil painting. It's a landscape painting. Light scatters off the pollen in all directions. Imagine standing one hundred meters away from the painting, spying at it through an aluminium tube. Draw lines in the air from the spec of pollen to the hole at the front of the tube. Draw enough of those lines and the shape of a long, narrow, solid cone will be formed. Think of this as a cone of light rays that have reflected from the pollen and have reached the tube.

Now put a group of lenses inside the front of the tube. These lenses allow the cone of light rays to pass through into the tube but bend each ray inwards so that the cone rapidly but smoothly collapses back down to a point. Let's say that the lenses we've chosen cause the cone of light rays to collapse to a point after travelling about 15cm into the tube.

Here's the tricky part. Look back out at the big painting, a hundred meters away. Visualise how the entire painting around the spec of pollen is made up of a billion other tiny light reflectors. A cone of light comes from each of these points, reaches the lenses at the front of the tube, goes through them and collapses down to its own point. All of these points end up arranged in perfect order to form an image of the oil painting. The place inside the tube where this image is formed is called the first focal plane.

Take a thin disk of clear glass and scratch some lines on it. Make a cross in the middle. Put this disk of glass in the tube where the image is formed and we have a reticle positioned in the first focal plane.

This diagram shows the first and second focal planes. For this scope, the reticle is in the second focal plane.

*****
Why is it called a focal plane?

The painting is a plane, perpendicular to our direction of view. The image of the painting formed inside the tube is a plane of focussed points of light. We've chosen our lenses well and all of the cones of light coming from the painting have been brought down to points, nicely focussed, at the first focal plane.

The painting has been standing in a three dimensional woodland scene, out in the real world. When the painting is taken away, only the parts of the scene that lie in the real world plane that it occupied will be shown in perfect focus in the image at the first focal plane. Perhaps the grass it was standing on or the tree it was leaning against. Objects in front of or behind the real world plane will be out of focus at the first focal plane, to some degree, depending on how far from the real world plane they are. They're out of focus because the cones of light coming from them collapse down to their points before or after reaching the first focal plane. When these cones of light reach the first focal plane their cross section is a disk of light, rather than a point of light. This makes them blurry at the first focal plane. The further an object is from the real world plane, the larger the disks of light coming from it will be at the first focal plane and the blurrier the object will appear to be in the image at the first focal plane.

*****

The cones of light rays coming from the scene go through the lenses as directly as they can, bending only as much as the lenses make them. The light from an object at the bottom left of the scene ends up at the top right of the image formed at the first focal plane. Light from the top centre of the scene ends up at bottom centre of the image. The image at the first focal plane is upside down and left to right. Good luck trying to hunt with that!

After a cone of light rays goes through the front lens and comes to a point inside the tube, the rays keep going. The light rays that make up the cone that has collapsed to its point cross over and continue on, creating a new cone that starts opening out. This happens with all the cones of light that have come from the scene and have gone into the tube.

We want our image of the woodland scene, now with our first focal plane reticle included, to be the right way up and the right way around. To achieve this, put a new group of lenses in the tube, a little further along from the first focal plane. These lenses stop the cones of light from expanding and send them along the tube shaped more like cylindrical beams. They also direct the beams towards and across the centreline of the tube. Put another group of lenses further along, shaped so that the cylindrical beams that pass through them are changed back into collapsing cones, which tighten down to points even further along the tube. The place where all of these cones of light become points of light, arranged into an image of the scene, is called the second focal plane.

Because the beams and cones of light have been moved across the centreline of the tube, the image at the second focal plane is now the right way up and the right way around. To look right the image has been erected, so let's call the lenses that did this the erecting optics.

Not only do we want the image the right way up, we want variable magnification. OK then, we'll need a shorter, narrower tube that fits neatly inside the main tube. Put the erecting optics at the front and rear ends of this internal tube and slide it back and forth. This makes the image at the second focal plane zoom in and out. And here comes the clincher. Because the reticle at the first focal plane has already been mixed in with the rays of light before they reach the erecting optics (which are now also the zooming optics) the reticle zooms in and out as well. When the zoom ring is turned, the first focal plane reticle grows and shrinks together with the image of the real world that is formed at the second focal plane.

Right. Nice to know. But why is that useful?

It's going to get a bit technical so I have to use italics.

If a variable power riflescope has its reticle located in the first focal plane, when the zoom ring is turned the reticle grows or shrinks together with the scene being viewed. Markings on the reticle will stay in proportion with the scene when they zoom together. The markings on the reticle can be accurately etched so that an interval between them corresponds with a particular angle of view in the real world, say, one thousandth of a radian. Because the markings and the scene stay together as they are zoomed, the angle of view defined by the markings will remain constant, regardless of the zoom setting.

The scope can be designed so that the angle of view defined by particular markings is matched to a certain number of clicks with the turrets. For example, the design could be that it takes 10 clicks to move the scene one thousandth of a radian past the reticle. This is a common design in Europe. It's also common to call one thousandth of a radian a 'milliradian', or even a 'mil'.

So now, when using the scope on a rifle, if the first bullet lands one milliradian to the left of the target, the turret can be turned 10 clicks to move the image to the right and the next shot will hit (provided an accurate rifle like a Mauser M03 is being used ;-) ). This will work with any zoom setting and at any range.

Let's read that last sentence again. 'This will work with any zoom setting and at any range.' Now that's useful.

Second Focal Plane.

If the reticle is placed at the second focal plane, its size and shape remains fixed when the image is zoomed. This is because the light beams have already passed through the erecting optics tube and are already zoomed in or out before the reticle interferes with them and becomes part of the image.

What are the advantages of having the reticle in the second focal plane? Well, for general hunting, when quick shots are often needed, it's good to know that the reticle will look exactly like it did last time, regardless of what has been done with the zoom setting since. It also ensures that the designer's choice of 'momma bear' thickness for the crosshair - thickness that is 'just right' - will apply at all zoom settings. The crosshair won't appear to be too thin at low magnification or too thick at high magnification.

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For completeness in constructing our riflescope, let's put some lenses at the rear of the tube. These will take the beams of light that have passed through the second focal plane and organise them nicely for our eyes. If we mount these in a tube that threads into the main tube we'll be able to screw them in and out so that we can adjust for our eyes and make sure the reticle is sharply focussed. If we are prepared to allow the reticle to be a little out of focus we can use this rear group to finely adjust the location of the focal plane to one side of the reticle or the other and hence adjust the location of the plane that will be in focus out in the real world. More on this in relation to the Zeiss Victory HT scopes later.

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As a example of how first focal plane reticles can be useful, imagine a father and son out shooting rabbits at 500 meters with Mauser M03s, in 243 Winchester and 6.5x55. Both rifles have first focal plane scopes with milliradian divisions on the reticles and turrets with 10 clicks to the milliradian. The son has adjusted his scope for the range and shoots with the 243 while the father watches through his scope on the 6.5. He sees the bullet impact the grass a little low and a little to the left. The rabbit crouches but doesn't run. The father measures the miss distance with his reticle and says, "2 clicks up and 2 clicks right." The son adjusts with a 'click-click' and a 'click-click' and the next shot hits. :-D

This video snippet shows Thomas Haugland quickly adjusting a scope that has the reticle in the first focal plane, to get shots on target.

Zeiss Victory HT Scopes on Mauser M03 Rifles

Scroll down for pictures.

For decades I've used the 'hold-over' method to adjust for range. Like most people who work at something for that long, I got to be reasonably good at it. I've enjoyed having to think about ballistics - what's the range and where will the projectile be relative to the line of sight? Whichever new scopes I bought to go with the Mausers, they'd be getting some use with hold-over hunting.

I was also keen to broaden my skills and use scopes with click-adjusting turrets, at least for some situations. That would be fun. Schmidt & Bender, Swarovski, Leica, Zeiss, Steiner, Kahles - I looked at all of these, comparing designs and features and working out what would matter the most for stalking, spotlighting and long range shooting. Maybe even for driven boar?

Sniping at rabbits and foxes with flat shooting and accurate varmint rifles has been a favourite discipline for me. A scope with clicking turrets would fit perfectly with this, especially if I moved beyond the 250 and 400 meter ranges I've shot to with fast .17 and .224 rifles. With adjustable turrets, even calibers that aren't scorchers become useable at longer ranges, provided the ballistics of an accurate load are well understood. The benefits will be less recoil, muzzle blast, barrel wear, cleaning and powder consumption and better case life. Probably better accuracy too. I have a match barrel in 6.5 x 55 being made for me by Mauser at the moment, as well as a 243 Winchester barrel in standard profile; these will go very well with clicking turrets. On my wish list are a mild shooting 222 Remington, then a 300 Winchester Magnum for bigger beasties at long range. Both will be in match profile.

As with camera lenses, the design of riflescopes is a complicated process of balancing optical and physical characteristics. Compromises have to be made. It's an engineering challenge which translates into a difficult decision for shooters. No riflescope will be a perfect solution, so the question becomes, which of the excellent products available has the fewest problematic design parameters given the intended application? Factors to consider in the optical space are light gathering, light transmission, centre resolution, edge resolution, distortion, objective field of view, subjective field of view, tunnel effect, field curvature, eye relief, exit pupil, diopter adjustment, parallax adjustment, zoom range, reticle style, reticle features and subtentions and reticle focal plane. In the physical space there's size, shape, weight, materials, tube diameter, tube length, mounting system and compatibility with a rifle, durability, weather resistance, hydrophobic lens coatings, position of controls, handling, availability of accessories, warranty and cost. For illumination there's which part of the reticle is lit up, how much of the target does it cover, is the adjustment stepped or continuous, by a dial or push buttons, is the range of brightness good for dark nights and sunny days, what's the activation method, automatic switch-off, battery life and battery changing. For the turrets there's diameter, profile, location on the tube, under-hang of the housing, elevation and windage range, click intervals, click tension and feel, rotation indicators, more tactile clicks, locking mechanisms, adjustable zero-stop, interchangeable range indicators, the markings and whether they're engraved or just painted. Phew! And there's still more.

When we pick up a scope we get to experience the designers' choices. Some of their decisions will make an immediate impression; others take much closer inspection to appreciate or understand.

My first look through a Leica ER scope was a real eye opener. How sharp is that! A typical Leica design; resolution and contrast were excellent but barrel distortion at low magnification was quite noticeable. Great eye relief, and the newer ERi scopes have illumination. The Magnus scopes also have illumination as well as six times zoom, thanks to an innovative optical design that Swarovski claim was stolen from them. A read of the legal proceedings in the UK is very interesting. I do wonder about the compromises that come with six power magnification though. I could be happy with a more conservative three or four times zoom.

Both the Leica Magnus and Swarovski Z6i scopes have push-button adjustments for brightness. They're slow to operate (the Magnus system is the better of the two) and are situated on rather awkward housings up on top of the ocular lenses. Like the ER and Magnus, the Z6i scopes made quite an impression; great optics, reticles, illumination and smooth adjusting zoom and diopter rings. The Swaros tended to be lighter than the others, which is good if that matters. Weight helps with recoil though and tends to come from thicker, stronger tubes.

The Schmidt & Bender hunting scopes I tried were good but didn't make the great impression I thought they would. At the time I was thinking about whether I wanted reticles in the first focal plane or second focal plane. I'll write a post on the difference between the two later. Watching the S&B front focal plane reticles disappear into the distance when the magnification was dialled down made me wonder how easy it would be to aim at a big, grumpy and fast moving animal I might meet up close. I concluded that second focal plane reticles are a good choice for general hunting, including stalking. A first focal plane scope with a fine reticle would be just the thing for longer range sniping.

Cue the entry of the Steiner Military 5-25x56 - an up-to-date technical tour de force. It's aimed at knocking the older Schmidt & Bender PM II 5-25x56 scopes off their perch and is making quite an impact, according to the knowledgeable folk at Finnaccuracy. Their site provides good information on the wonderful Multipurpose Sniper Reticle they have designed, which has been picked up by Schmidt & Bender and Steiner, as well as by Kahles for their 6-24x56.

So, I was warming to the idea of having scopes with a moderate zoom range and reticles in the second focal plane for stalking and a tactically oriented, first focal plane, higher power scope with clicking turrets for sniping. But which ones?

While doing my research I started picking up references to the new versions of Zeiss Victory HT scopes. Zeiss are bragging about achieving more than 95% light transmission with a new formulation of Schott glass. This would be very handy for the dawn, dusk and night shooting I do. I contacted some early adopters who reported they were very happy, particularly with performance in moonlight. And, the Victory HT scopes could be ordered with 'Absehenschnellverstellung'. I'll be calling that ASV. It's a system that allows the shooter to install graduated range marking scales onto the elevation turret, chosen to match the ballistic curve of the ammunition and projectile in use. Zeiss provide a computer program to help identify which scale to use. The latest Victory HT scopes have ASV+ and included in delivery are nine graduated rings, as well as a standard ring with an old fashioned linear scale. This one's for folk who prefer to do their ballistics in the field rather than before the event in their study at home. Folks like me; until I get the programming sorted out, that is.

The Zeiss Victory HT scopes also have illumination with a particularly fine dot. It's the same size as the thickness of the crosshair. It's adjusted by a continuously turning rheostat, from very dim to very bright and remembers its last setting. The Victory HT scopes provide four times zoom; that's momma bear territory in my book; not too little and not too much.

The highest power in the Victory HT scopes is a 3-12x56mm, meaning that Zeiss have designed these for a variety of general hunting purposes. It also explains why Zeiss have not included parallax adjustment. Their word on this would be that for general hunting the shooter will not want to, nor have time to, fiddle with a parallax control. As much as I appreciate parallax adjustment in a scope, I have to agree with Zeiss in this respect. A point of contrast can be seen with Leica's Magnus 2.5-16x56, which does have a parallax control, to cater for its higher magnification. The other Leica scopes, Magnus and ERi, have parallax fixed at 100 meters, just like the Victory HTs. I'll write more on parallax later.

Given the Zeiss Victory HT's excellent light transmission, the ideal illumination system, the ASV+ turret calibration and their clean lines, these are the scopes I chose. I had asked enough questions of contacts and sales staff ahead of time to be confident that the Mauser 30mm rings would provide enough clearance for the Victory HT 3-12x56mm. The photo below provides the proof. This is an ideal mounting.

Zeiss Victory HT 3-12x56mm on Mauser M03 using Mauser 30mm steel rings

The next photo shows the Zeiss Victory HT 2.5-10x50mm.

Zeiss Victory HT 2.5-10x50mm on Mauser M03 using Mauser 30mm steel rings

And this one is the Zeiss Victory HT 1.5-6x42mm.

Zeiss Victory HT 1.5-6x42mm on Mauser M03 using Mauser 30mm steel rings

Keen observers will have noticed that the blurry box in the background is not from Zeiss. Stay tuned for more on that.