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Mark;

Thanks we all will be waiting to see your photographs, especially from an workshop of one of the innovators of modern technology to traditional made guns.

In the meantime, I will speak to the issue that is next in the building of the subject DR, and that is the making and installation of top and bottom ribs, as well as quarter rib for use with a scope and the front sight ramp. These items can easily be the source of too much weight added to the barrel, if one is not diligent.

In order to have minimum weight added to the barrels, I searched for a source of thin high quality steel shaped to the radius I needed for building ribs. I needed something in the range of a 1.5 inch diameter thin wall tube to cut a radius section. I was search for some such tubing with maybe .025" thickness. Where I found the source of strong thin wall tubing was with builders and suppliers of materials to the automobile racing business. They need very strong and lightweight tubing in the building of their automobiles, motorcycles and so forth. I found just what I needed on eBay from one of these firms.

I silver brazed a fore-end loop to the position I needed between the barrels as well as a cross piece between the barrels at about 11 inches from the muzzles, being careful to try to keep the barrels in the convergence angle as well as horizontal alignment.

The DR was test fired 2 times per barrel in an appropriate fixture with very high pressure loads.

I then built a temporary to mount a scope (as illustrated in this photo below) and tested the rifle impact point at 50 and 100 yards.

Although this photo is not of very good detail, you will be able to see that I milled a temporary ramp with dovetail slots to where a scope could be mounted and attached this ramp to temporary thread tapped holes to the top of the fore-end loop and another hole that I drilled and taped in the barrel support at the breech(this support was silver brazed in place at the time I brazed the barrels to the shoe lump platform).

The testing of the DR with such a temporary scope mount, or for that matter a open sight, is not necessary. However, I did it as I was going to stop in my rifle building process and develop a wildcat load for the DR and I knew that this effort would take several weeks or a month or so. Which it did. The load that I wanted to develop in the .38-55 McPherson cartridge case was a load that would equal the old .375 2 1/2 inch Holland & Holland flanged nitro express cartridge, but without the cost and expense of being able to purchase a couple of hundred .375 2 1/2" flanged empty brass cases, chamber reamer, loading dies and so forth--all of which would be more expensive than the route of using .38-55 McPherson.

I built the ribs, quarter ribs and so forth and attached them with tin/lead solder. I think all of you will be familiar with this task and know that it is time consuming. Purchase a copy of the video "A look Inside Holland & Holland" by www.gunmakersrow.co.uk. to view each step of how H&H builds guns and rifles, even the explanation and illustration of their DR barrel regulation and their barrel regulation wedge is there. The video may be difficult to find now, but it is out there even though it was made some 5-7 years ago. It is worth every penny it cost. I paid USA$50.00 for mine 5 years ago.

After the the rib installation it was time to regulate the barrels, which took some time to do. I use the Holland & Holland method of a vertical wedge between a machined front barrel bloc that fits the OD of the barrels at the muzzle as the photo below illustrates.

After I have the DR shooting the way I want at 100 yards, I build a solid front barrel bloc for the correct distance between the barrels at the muzzle and solder it in place. The following 2 photographs are from the Holland & Holland video that I discussed earlier and they illustrate the vertical wedge and the final bloc as I have just discussed. After these two Holland & Holland photos is a photo of my DR's muzzle and the muzzle bloc.

Edited by CptCurl (06/05/17 09:55 PM)

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