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Gehmann-Konstanz 5.6 x 61 vom Hofe

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  • Kiwi_bloke,

    Your rifle must have quite a bit of free-bore if an inch long bullet will not touch before it falls out of the case. This may well contribute to the velocities you report. Weatherby was a great fan of long free-bores to keep pressures in check and gain velocity. I myself prefer it if possible as it certainly does both and I don’t believe that practical accuracy suffers at all.

    The 77 grain bullet I make was copied after a factory bullet and measures .958” long. This is with a pure lead core that just shows at the tip and a rebated base. Unfortunately, RWS are all but impossible to find here in the US and it appears that Degol of Belgium uses equipment made by Dave Corbin here in the US. I wrote a long winded dissertation earlier in this post about how I got started using 22 long rifle cases at first and then 22 magnum rim fire for making bullets so I’m not going back over it. Now I use Richard Corbins’ swaging equipment and dies and find them excellent.

    You mentioned the Lee Factory Crimp die several times and I use one for 45ACP. Do your bullets have a cannelure? It seems to me that this style of crimp is most effective in a groove. I can groove my bullets but usually don’t for the vH but I have been experimenting with a wide band rather than a cannelure to cut down on the contact area but these are much bigger bullets of 475 and 500 caliber.

    I hunted in Africa with Dave Wolf and knew him fairly well before he passed. He had a fine magazine (and it still is) for handloaders. However, I have used Shooters Choice and it does work but I prefer Hoppe’s Bench Rest for normal cleaning and copper removal. I also use JB Bore cleaner that is excellent for heavy fouling and my own concoction of Hoppe’s mixed with Bon-Ami as a paste. I know is sounds strange but it cleans and polishes but doesn’t scratch or take out any metal that I can measure and I have been using it for years.

    I can only say that if you are seeing 3,500+ using 4831 without any pressure signs then you have a remarkable rifle indeed. I just don’t like to run the faster powders in a cartridge with such a low expansion ratio but that’s just me. I think that 4350 is an excellent powder but don’t use it in the vH.

    I have two sets of vH dies and both are a little tight in the base so I will look into the Hornady universal seater. I like their regular dies and have several sets and all make very nice cartridges. 9.3 x 62 brass is rather hard to come by but we are knee deep in 30-06 and it makes a usable case for the vH but the head is slightly undersize. I only have a handful of HH cases and only use them for special occasions. It has started raining here so no shooting plus I need to repair a problem with the rear base on that rifle.

    One wouldn’t think loading for a 22 could be all that complex.

    Thanks, Diz

    Comment


    • It's still blowing hard here, but I got to the range anyway, needed 6+ staples per target to hold them on. 50.0 grains of IMR 4350 with a 70 grain Hornady spire point gave 3,397 fps and a quite stiff bolt lift, but no primer cratering. The same load with a 77-grain Degol bullet produced 3,300 fps and a normal bolt lift. Of course, these loads could be unsafe in any other rifle.

      On the plus side, in an old Urbas Drilling in 8x57R .360, IMR 4350 produced 1,704 fps, which is less than the 1,820-1,870 fps predicted in Handloader 139, (May 1989), but better than other powders trialled in this particular rifle. Re19, for instance, using a published load, gave 1,552 fps. You could probably walk down to the target and wait for it to arrive. However, this Drilling is very accurate. This calibre shares it's name with the 8x57R Mauser, but is actually quite different.

      Back to the vom Hofe round; H4831 produces 3,517 fps with a Federal standard match rifle primer, slightly less with a F210, CCI or BR2 using the same load. Bolt lift and extraction is easy, primer cratering is minor. The idea of using H4831sc comes from Jeff Munnell's published data. Looking at Handloader's Digest, 18th edition, there are 3 pages of powder burning rates, fastest to slowest. H4831sc is 14 places off H870. I suspect some of the newer powders with slower burning rates around the H870 mark, such as Retumbo for instance, might have application for this over-bored round. I find it amusing that Herr. vom Hofe and Walther Gehmann came up with the idea of using a .404 case, (i.e. 7x66 SE vH), years before the modern "Ultra-Mag" era. What could they have done then with these newer powders?

      Actually, I noticed since that old DWM packets of 5,6x61 SE vH are marked "bullet....25mm lang(long)".

      In terms of freebore, the Degol 77gr has 0.121" freebore, the Hornady 70gr 0.185" and the Speer 70gr 0.096" in this rifle. Most of Weatherby's earlier Sauer made rifles have plenty of freebore. One well-researched history claims that Roy Weatherby was inspired by vom Hofe rifles, but since so few of them were arrived when sporting Mausers flooded the States after the war, that led him to develop his own similar cartridges.

      I did fire off some Lee Factory Crimped 5,6x61 SE cases today for comparison. A nice group but I haven't yet found the un-crimped data to compare. I must put all this on spread sheets. However I fired off some .22 K-Hornet today, crimped and uncrimped. The difference was exactly 3 fps.

      If you get that Hornady bullet seater die, can I suggest putting a Forster lock-ring on it.

      Lastly, I fired off some 60-grain Nosler partitions today from an old Savage-Anschuetz 5,6x57 RWS at 3,710 fps and got a 1,1/8" group even in all that wind. The powder is ADI 2209 and the published data from Nick Harvey's reloading manual. That group looked a lot smarter than today's accuracy from the 5,6x61 and made me wonder if the RWS claim, that their cartridge is better balanced than the older vom Hofe round, is not unreasonable. No pressure issues in the 5,6x57.

      I have looked at using Corbin's swage dies for .360 and .300 rook rifle bullets, but I'm not too sure I can get lead wire to use in New Zealand. I had a custom mold made instead and use lead range scrap from a .22 "smallbore" (i.e. rimfire), range.

      Thanks for all your ideas to follow up. If you (and/or Mike?), drop me your email address as a personal message, I can send Jeff's scanned data.

      Comment


      • Kiwi_bloke,
        If Diz sends you his email address, I would appreciate it if he sent mine as well(he has it). It would be interesting if you started another thread for the 8x57R/360. I too have been playing with a drilling in that caliber, and discussions more detailed than can be taken up here would be informative. The same would apply for the 5.6x57. That might inspire me to get off my tail and finish a 20 year old project, started because I have a goodly amount of factory ammo.
        Mike

        Comment


        • Kiwi_bloke & Mike,

          PM sent earlier with mine and Mike's private e-mail addresses. I am a bit surprised some of the other vH guys haven't chimed in as well. I agree that vom Hofe was way ahead of his time where high intensity cartridges are concerned.

          I'm sure you know about this but ADI has an "equivalent" chart on their web site that lists ADI 2209 as = IMR 4350 and several others. I know they are making several powders for Hodgdon.

          Mike I am going to be turning my attention back to the 12.7x44R fairly soon and may have something interesting to report.

          Thanks, Diz

          Comment


          • Diz,
            Thanks for sending my email to Kiwi_bloke. Between 5.6x61 Vh, 8x57R/360, and 12.7x44(42 for mine)R, this is a pretty eclectic group. I don't remember now which thread we discussed the 12.7 in.
            Kiwi_bloke,
            I don't know where you live, but if there is demolition of buildings in the area, old shower pans( used to waterproof shower floors) are a good source of pure lead. You may find new shower pan material in building supply stores; plastic is used now, but they may have old lead in stock. Where X-Ray machines are replaced, you may find lead counterweights, one of which may be a lifetime supply of lead. If walls had to be removed to replace the machine, you may find lead shielding. Large General Contractors of Demolition Contractors may be good sources, as well as scrap dealers.
            Mike

            Comment


            • Kiwi_bloke,

              Attached is a very quick drawing of a lead wire maker I made a long time ago when I started making jacketed bullets. The body and plunger are just scrap steel and could be whatever you have. The plunger on mine is about ¾” in diameter and the extruder part about 1-1/4” diameter. Only two dimensions are really important and that is clearance between the body and plunger should only be a couple thousandths to keep the lead from pushing in and the hole in the bottom needs to be the size of the wire core you want. I have since improved the design by tapping ½-20 thread for a set screw where the orifice is. Then I just drill the set screw with the right hole and can change it to whatever size I want.

              I make up the alloy I want for the core and pour it into the extruder body and let it harden. Then put some heavy grease on the plunger and put it in my shop press. It doesn’t really take much pressure to force the lead out as long as you keep the plunger diameter reasonable. Surprisingly the plunger will usually come out without much trouble when you’re ready to reload it. I usually don’t press it all the way down but leave some space between the top of the plunger and the body so you can pry on it if necessary.

              Finally got the issue with the rear scope mount sorted out so I will try to shoot it again soon. By the way, I had a senior moment and deleted your private e-mail address without saving it so please resend when you have a moment.

              Thanks, Diz




              Lead Wire Extruder.jpg

              Comment


              • Ok, Just got back from shooting the vH again and I am a pretty happy guy. It seems that I have found a powder to replace H-870 at least for me. I only shot five as that is what I had left from the batch of ten so this is fairly weak data but it got my attention. Here are the numbers out of my 35P:

                3406 - Hi
                3391 - Lo
                15 - Dif
                3401 - Mean
                5.97 - SD

                This was using a Remington 25-06 case reformed and 56.1 grains of Vihtavuori N-570 behind a Hornady 80 grain A-Max resized to .228". I adjusted my program to compensate for the smaller case volume and it filled the case to just the bottom of the neck and predicted 3396 @ 54,700 psi. That is very close to actual. The standard benchrest target is attached. I measured .562" center to center but it was a perfect day for shooting without a breath of wind. And it seems the repair to the rear mount helped as well.


                vom Hofe Target.jpg

                This load worked in MY rifle but please be reminded that your results may vary (a LOT too) and load for this cartridge VERY carefully. Prudence is important here.

                Thanks to all those that had the patience to follow this thread. Diz

                Comment


                • Man, those are good numbers!

                  Comment


                  • Sharps,

                    Thanks, they are nice but one run of five doesn't prove too much. However, with an SD that low I doubt if I am going to see much variation down the road. I was a little surprised at the bullet penetration as well because I had the target backed up with an 8 x 8 of yellow pine aged to rock hard and they went through. The first punched out about a quarter size exit and that is very interesting for what I thought was such a frangible bullet. Now to drag out my Cape gun and drilling and get something working for them!

                    Thanks, Diz

                    Comment


                    • I'll just say quickly here by way of response to earlier comments, (because it really does belong in a separate thread), but the reason I use recovered range scrap from a .22 rimfire backstop, is (1) because there's lots of it, (2) it needed cleaning out anyway and also, (3) it is designed for the same velocity as rook rifle bullets. They are also the same technology as a .22LR, (heeled, outside lubricated, no jacket) and target lead is held to very high standards. For instance, Eley make their bullets in the absence of oxygen, because lead-oxide is one of the causes of fliers. I'm not sure how un-oxidised it is by the time I get it, but it seemed to make more sense than car wheel weights. Besides, they're quite hard to pry off in car parks

                      Re N570, that's one of several slow burning powders which have appeared in recent years, that seem to be naturals for the vom Hofe line. I get the impression that, go back a few decades and IMR powders were just about all there was.

                      Comment


                      • Kiwi-bloke,
                        My comments about lead sources were not offered as criticism, but only as possible additional sources. We all use what is most available to us, and that is part of what makes it fun. I use a good amount of wheel weights and can report that not only would they be hard to pry off, the resulting material would be hard to "draw" into wire as well. You are correct that some of we "old farts" tend to use IMR powders from our distant youth. When the powder cabinet is full of old numbers that are useful, and new numbers cost $24-$32 lb., we just use what we have. It doesn't mean the new numbers are not good. Don't worry, todays new numbers will be old too, when todays "young lads" are the "old farts". Some of the numbers overlap anyway, 4350 is a good example.
                        Mike

                        Comment


                        • Mike & Kiwi,

                          I just wanted to comment on clean-up after shooting this last group. The bore again was clean to the eye with no un-burned powder. I did see a good bit of green on the patches at first but it cleaned up without any extraordinary measures needed. I am going to load 10 in HH cases to try next.

                          For hard lead bullets, I melt down magnum lead shot either West Coast or Eagle brands and find it very consistent, casts nicely and is quite hard. Hard on the wallet too.

                          I would like to see a thread on the 8x57R 360 as it should be very interesting. I am ready to retry my 12.7x44R again as soon as my honey-do list gets finished.

                          Thanks, Diz

                          Comment


                          • I thought Kiwi was going to start a 8x57R/360 thread. I loaded 30 yesterday for the up coming hunting season.
                            Mike

                            Comment


                            • I just saw that Sierra is making a new "tipped" MatchKing in .224" / 77 grains but with an extra heavy jacket. According to them they don't expand much if at all at normal velocity for these bullets. I am thinking this may be the perfect combination for a vH SE to make it a true deer cartridge once again. I am going to order a couple of boxes to bump up and try.

                              Also, I have several boxes of Hornady .227" / 70 grain bullets that I have no longer have use for. Anyone interested can have them for shipping.

                              Comment


                              • Diz,
                                If the offer still stands, I would like to have them. If you email me the amount, I will send a money order. You can send them by USPS in one of their "if it fits, it ships" boxes, since there is nothing dangerous included.
                                Mike

                                Comment

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