The first job of the next leg is to fit the leg limiter. This has two lugs on the centre column and on the left leg. Between this and the attachment at the head of the tripod it helps the user to keep the elevation adjustment vertical, even on sloped or bumpy ground.
When deployed, the limiter sits pretty much horizontal. The collar it is attached to on the leg slides up and down, with a stop at the top of its travel to make it level out. In these two pictures you can also see the elevation adjustment handle. This piece of steel bar was bent and is screwed and pinned in position so that it can’t rotate without operating the elevation screw.
The feet are welded onto sockets that fit over the bottom of the legs.
And are in turn are spot welded onto the legs. These feet will allow the operator to dig the legs into the ground for stability when firing.
The windage screw has a metal sheath, which I’ll be adjusting to be a nice, close fit. It will also have to have a tooth of some kind to work against the screw.
With some rather happy timing, these 3D printed parts then arrived. Printed in ABS for strength, if they prove to not be up to the task I shall try casting them in aluminium. I suspect they’ll do beautifully though, these are very solid shapes.
Roughly put in place, the mortar is really taking shape now. To finish off these parts, I need to fit a large screw to the barrel clamp and screw together the two halves of the windage unit. The windage screw also needs a little modifying to remain locked into the unit, rather than walking out either side.
The two halves of the windage unit screwed together. This is a very rigid unit, as it needs to be to function. The screw thread is very stiff and it will need a little modification to work smoothly.
With a little time on the lathe, I reduced the ends of the screw thread down so that they ran smoothly in their mountings. I also drilled and tapped each end for the stoppers that prevent it from leaving the windage control.
The windage adjustment dial has a folding handle, like the original.
In place, it sits well and works quite smoothly. I think the barrel vise will need a little re-enforcing for use but it’s not bad even as is.
A quick demo, it’s a bit awkward videoing and operating it at the same time but it’s easy to use.
The last bits are the baseplate and baseplate ball, plus a fair bit of finishing. This thing will take some serious painting!
You can see the previous build post here.
If you are interested in the history of the M2, you can check out the introduction article here.
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