Gehmann-Konstanz 5.6 x 61 vom Hofe

[wernerhelm]

Proof marksimage.jpgimage.jpg

[Axel E]

Barrel made by the well known Zella – Mehlis barrelmaker MM = Max Möller (then company name). Barrel really made and chambered by son Gustav Möller, G.M. Proofed by the Zella –Mehlis proofhouse, spruce in heart mark, in 1240 = December 1940. Eagle/N = nitro proof, eagle/I = Instandsetzung = overhaul, repair, maybe for a replaced barrel. Hermann Weihrauch got the original order for the rebarrel job and signed as the responsible gunmaker. BTW, Hermann Weihrauch mounted scopes in WW1, only later, 1942 on, in WW2.

[Kiwi_bloke]

Hi guys

As the owner of several vom Hofe rifles I trawl the internet for info. There is certainly a wealth of it here.

About the makers:Gebrueder Gehmann, Kreuzlinger Str. 45a, Konstanz: In fact Konstanz is a town next to a lake that we in the west call Lake Konstanz, but Germans actually refer to as Lake Bodensee. Regardless, the town name remains the same. So Konstanz is a place, not a model name. Walther Gehmann marketed rifles typically marked Gehmann Karlsruhe after his shop in that city. So there is no reason to assume the two entities are linked.

Walther Gehmann is the "inhaber", (proprietor), of the vom Hofe line as he later purchased the rights after Ernst August vom Hofe was killed in Pommern in 1945 shortly after the Russians arrived where he was stationed. So I don't think there's any reason to assume this rifle was made by or for Walter Gehmann as he was not yet the "inhaber", of the vom Hofe line if this rifle was made in the 1940's while Herr. vom Hofe was still alive.

Gebrueder means Gehmann Brothers. I have a 5,6x61R SEvH Drilling being delivered to me, so I haven't seen it yet. It's also described as "Gehmann Konstanz". It's serial number (actually, it is the maker number), is 40.xxxx so I'm reasonably sure it was actually made by Ludwig Borovnik of Ferlach, Austria, and then retailed by Gebrueder Gehmann in Konstanz. There's nothing very unusual about someone else making firearms for a retailer. I have a Bock-Drilling, with the name Zeitler on it, but actually made by Fanzoj of Ferlach, according to the proof-house I contacted about it. Many English guns were made by Webley and sold under other famous names.

I have another 5,6x61 rifle that is made on a Mauser 98 action and it has the name Roell stamped on the barrel inside the stock mortise. It was made by Walther Roell after WW2 and I even have the proof-certificate for it. It's an accurate shooter and normally shoots around 3,500 fps with handloads using H870, (which I no longer use, too much fouling even when I use a custom Lee factory-crimp die), or H4831SC. I was quite content with that, I think the data all came from an article by Mr Munnel in the Accurate Rifle magazine. However since Hodgdon's have since released IMR4350, I used the Cartridges of the World data and found 3,700+ fps - albeit this is a very hot load. I fired one round and pulled the rest. I have since backed off it quite a bit and I'm waiting for some fine weather to try the somewhat reduced load with 77-grain Degol and also 70-grain Hornady bullets. The latter seem to work just fine at 3,500 fps or less, and should be just fine for the rimmed version that Walther Gehmann factory ammo is listed as Vo 1,000 m/s (3,280 fps). RWS bullets in .228" are also very accurate. Regarding my hot-load experience, yes, I should have worked up to it. Naughty me.

I lost a skyscreen year back using some very old Speer .228" bullets at these high speeds, 3,500 fps. I simply don't use these Speers any more. They may have deteriorated as the plastic box they were in fell apart. It was Hobson's Choice at the time, (meaning that was all there was).

The brass I use came from Germany, Horneber and Gehmann. The latter may also be old stock because the necks split at an alarming rate just putting the virgin brass through the FL (RCBS) die. I cured this by annealing the neck/shoulder only in moulten lead for 5 seconds, then quenching. No more problems after that. But the primer hole must be blocked with a SPENT primer. For bullet seating I was lucky enough that Hornady has some in-line seating dies custom designed just for this cartridge, which has a thicker neck than the old .22 Savage Hi-Power. I also use a Hornady tool to straighten out any "wobble" in the bullets so they only have about 1 thou run-out. I just forget it's marketing name, but nothing leaves my reloading bench without it being used - not even factory ammo!

The Roell will print a 5 shot group of Degol bullets just under 1". Interestingly, if I shoot the RWS bullets, they also print nice tight groups, but several inches to the right of the Degol. The Belgian made Degols are made for this calibre and have strong jackets to cope with the ultra velocity. They also have the original "paraboloid" nose shape, which incidentally is the same as a Zeppelin nose shape.

I've also got another 5,6x61 S.E. v. Hofe on a Frankonia retailed Mauser 98 action. "I've cornered the market", as one of my friends said. If there is a "vom Hofe Owners Club", then the South Pacific chapter has just opened.

[Diz]

Kiwi-bloke,

Welcome to the forum and it's always good to find another vom Hofe owner/shooter. So far I think that makes exactly four that I know of and they are all in this club. Some rarefied membership indeed. Your experiences pretty much match mine but unfortunately I have never had any Degol bullets to play with. I make my own that are very close copies of bullets pulled from old Gehmann ammo. All that stuff was mentioned previously. Maybe there should be a vom Hofe owners club!

Thanks, Diz

[Kiwi_bloke]

Many thanks for that welcome.

Egun (a German on-line website for auctioning firearms), does have vom Hofe rifles for sale fairly regularly. But getting permits for firearms out of Germany is getting to be more and more difficult. There are some to be had at good prices, mainly because of the German hunting laws that require a rifle of at least 6,5x57 or 6,5x55 (calibre diameter and energy), to shoot game larger than roe deer and chamois. Because wild boar numbers have exploded, seasons for them are liberal. But if you're on a deer hunt and a boar walks past, you cannot legally shoot it with the likes of a 5,6x61 SE or 5,6x57 RWS or even the 6x62 Freres. So I would think quite a few rifles are being traded by frustrated hunters. From what I can gather, the wild boars have exploded because many are living quite safe from hunters inside the many jungles of biofuel crops.

My son shot his first fallow buck, a whitetail sized deer, with a 5,6x57 using a 74-grain RWS bullet. It fell over backwards. I dressed that deer out and it was never going anywhere. This rifle uses inserts which have been much maligned. But frankly, they shoot perfectly well. He missed a hare at 100 yards using the .22 Hornet insert. It parted the hair between the hare's ears. A smidgeon lower and it would have been casserole. Interesting perhaps, this is a Savage 110 action reworked by Anschuetz with double-set triggers, hogsback comb, Schnabel tip and claw-mounts among other features. John T. Amber (Gun Digest editor), had one of the early ones and I grabbed my chance to get one just like it. I think the 5,6x61 S.E performance eclipses it, however. But the .22 WMR and .22 Hornet inserts makes the 5,6x57 RWS rifle ideal for working up a young chap, as there's no recoil to begin with and they're quite accurate, despite the twist-rate compromises going on. The 5,6x57 RWS is a true .224" bore which means Nosler's 60-grain partition is quite at home on game up to whitetail size. Brass, however, is just as hard to get as the 5,6mm vom Hofe rimmed and rimless. At least the later can be formed from other cases, (such as .30R Blaser for the 5,6x61 rimmed version), but the thick 5,6x57 neck cannot be replicated to my knowledge.

[Diz]

Kiwi-bloke,

There are a lot of fellows here that use inserts in full length and swear by them as far as accuracy goes. I have limited experience with inserts preferring to shoot them as they are. To me the Savage 110 is the sleeper of the rifle world. I have never seen one that didn't shoot exceptionally accurate and all dolled up with set triggers and such should only make it better.

I would think a heavily jacketed 77 grain or heavier or a partition would settle a boar without much trouble but the law is the law. Unfortunate but I don't see a flood of vH's arriving here in the US.

I am not that familiar with the 30R Blaser but i understand it has a bit more power than the 30-06. Mike Ford has a rimmed vH and I am sure he would be interested in this case as an alternative. Making cases for either has always been a chore.

Thanks, Diz

[mike ford]

As Diz said, I would be interested in 30R Blazer cases, if the actual measured head diameter is really larger than 7x65R. Measured dimensions often don't match design dimensions.I have some virgin RWS boxer primed cases for the 7x66 vH SE, I would trade(I could also use other 5.6x61R cases, including berdan primed). BTW, the "inserts" Kiwi-bloke mentioned are insert cartridges(see my "side bar" evaluation of a 22LR insert for 5.6x61R that Axel very kindly provided).Diz's use of "full length", indicates he is thinking of einstecklaufs(EL)(insert barrels), which are entirely different, but are also very useful.
Mike

[Kiwi_bloke]

The idea to use .30 Blaser as a parent case for 5,6x61R comes from the 7th edition of Wiederladen, (the RWS reloading manual).

And yes, the 5,6x57 RWS uses insert cartridges, rather than insert barrels, the latter of which are typically for used within combination guns in calibres like 5,6x50R, .22 Hornet, etc. The 5,6x57 RWS has a set of 2 insert cartridges, one for .22WMR and one in .22 Hornet. The .22WMR one needs a small spacer to transfer the striker force. Both need a small brass rod to knock the spent cases out. I think they're made by Walther and come in a small plastic case.

There's also reduced cartridges for sale in Germany which use full size case outer dimensions, but a much reduced inner volume for much reduced loads.

I also have here a couple of inserts that are a bit of a hybrid having just a very short barrel inside a shotgun-sized outer case. So for instance, I can carry around a 16 gauge one of these in my pocket loaded with a .38 Special which makes a useful finisher for a wounded animal shot with a Drilling. There's another which is a .22LR inside a 12 gauge and this probably has a role in dispatching vermin in traps. They're both made by Lothar Walther. Accuracy is quite good for their intended purpose. When you think of a .22LR being a rimfire, and the need to offset the .22 barrel to meet the striker correctly, it's surprizing they work as well as they do.

While we're talking about Einstecklaufen, (insert barrels), does anyone know if used full-length ones that are originally custom fit to one combo-rifle barrel can be shortened to fit another? Does that muzzle adjustment sleeve typically just unscrew (or un-solder), allowing a gunsmith to adjust the length downwards? Quite a few of them in used condition come up for sale on Egun. I wonder too, if one that was fitted in a full choke would be suitable to fit to a modified choke barrel? I understand the need to index them on the extractor by creating a small milled recess but no one can tell me if they can be adapted for reuse.

[mike ford]

Kiwi_bloke,
While I have experience with different makes of the older type, short(20 cm,etc.) EL, I never owned one of the full length ones. There are several different makes, now, and each likely uses a different method at the muzzle. I would be shocked if it is not possible to alter them to fit a shorter barrel. If you are not able to make the alterations yourself, the cost, together with the cost of the used EL, should be considered. For whatever it is worth, they are avaliable from some makers( such as Zimmermann) in many calibers, up to 9.3x74R(the most powerful are not used in drillings though).
Mike

[Diz]

It has been a long summer and now that the weather has gotten a lot nicer I thought I would pick up on trying to find an alternative powder to replace my old standby H-870 for the 5.6x61vH. After looking at about a half dozen powders listed in my QuickLoad I decided to try Vihtavuori N-570 with an 80 grain Hornady A-Max bumped to .228” diameter. Unfortunately, I had some problems with an old Pact Pro chronograph and couldn’t get a single velocity for the five shot string I fired before packing it in. The group measured about 1” at 100 meters which isn’t bad but I want to see the numbers from the chronograph. The cases were reformed Remington 25-06 and worked well using Mike’s base tape trick. There were no pressure signs and the bolt opened with one finger. The primers still showed some radius left in the corners. That corresponds well with predicted pressures from the program of about 50,000 psi. The best news is I fired this string with no cleaning at all and the bore was completely clear of unburned powder. This never happened with H-870. I’ll bring my Oehler 35P next time and have more to report.

Thanks, Diz

[Kiwi_bloke]

H-870 is always dirty and even after a week, you have to clean the barrel again as it seems to work out of the barrel 'pores'. I got Lee to make a custom Factory Neck Crimp die to increase the burn efficiency, (I got the idea from Germany, probably intended for this purpose). Good tool but not sure it helped a whole lot. When I found a load for 2 different Hodgdon powders, I never used it again. I asked Hodgdon about this and they didn't think H-870 was suitable for the 5,6x61 SEvH.

I took out an Oehler 35P skyscreen using some old Speer bullets in this calibre. I think the bullet flew apart and took out the screen on its' way. The box they were in had nearly turned to plastic dust and the serial number on it was so old that the Speer factory couldn't date it. But they were at the time the only ones available in .228".

[Diz]

Kiwi_bloke,

H-870 was to me the best powder for the cartridge at the time, Hodgdons opinion to the contrary and both Mike and Axel believe the original cartridges were loaded with it. I only had one original at the time that was dismantled to copy the bullet profile to make forming dies and never tried to match the powder. Now that H-870 is no longer available and stocks have pretty much dried up I have been looking for alternatives. I don’t believe there are many powders out there that show the flexibility of H-870 in building pressure in a very linier fashion especially in such an overbore cartridge. That powder was very accurate in my rifle and made many sub-inch 10 shot groups on a good day. But it required cleaning every three shots or the groups opened to plus-foot and off the paper with home made bullets.

Hornady still makes a .227” diameter 70 grain bullet but my experience is that they come unglued at anything above 3,200 fps or so. The one inch five shot string I mentioned in the previous post would have been smaller except for one that opened it up. That was showing a wisp of lead spray at the entrance hole of the target and indicated that something was going on with that bullet.

I may be assembling some loads using the same bullet as I tried this time but with Norma MRP-2 powder to test along side the N-570 loads. My QuickLoad program shows it as a good possibility. Other Hodgdon powders are either too slow and bulky or show rapid pressure rises for small increases in powder. That trait make me nervous.

Just for fun, I ran the load that you mention earlier as being hot with H-4350 but using my 77 grain bullet as a model since I don't have any data for your bullet. The program showed a load of 56.1 grains of H-4350 giving exactly 3700 fps but at a predicted 85,000+ psi. That is very high pressure indeed! I had to go all the way down to 50.6 grains to get the pressure to 63,000+ and right at the CIP limit for the cartridge. That load showed a predicted velocity of just under 3,400 fps. This is an 80% loading density and one reason why I like my powders extra slow for this cartridge.

Thanks, Diz

[Kiwi_bloke]

What does Quickload show for H4831sc?

If you send me a personal message to respond to, I'll scan and send some published data I have here from Jeff Munnell.

I presume you have seen the data published in The Rifle Magazine, Jan/Feb 1971 by Al Miller. This uses IMR4350 and H4831 chronographed over an Oehler 10. He tried but didn't persist with H870. Jeff, ironically, purchased the very same rifle.

I also have a copy here of Wild und Hund, 25 Mai 1986. This refers to "new data since 1983 for the 5,6x61 using Hodgdon 870 making a loading density of 100% possible". For that reason I purchased several containers of it, but got faster velocities and cleaner burning with H4831 using Mr Munnell's data.

My Oehler 35p showed my loads were not as fast as Jeff's, perhaps due to free-boring. However they were going faster than 5,6x61 rounds then being sold commercially in Germany and with groups just under 1" so I was happy with that. My brief IMR 4350 experiment definitely showed higher velocities than I have been used to, but the pressure figures you give are sobering. We are having high winds every day here and, of course, I have to earn a crust as well. But if it calms down this weekend, I might have some velocity information about more prudent loads of IMR 4350 using both 70-grain Hornady and 77-grain Degol bullets.

That custom made Factory Crimp die did help improve H870 combustion. I simply first sent them an old case with loaded bullet, but it had to be drilled through both sides and not have a primer, so anyone could see it was not loaded. I have here a 2004/5 catalogue from Treibel in Berlin, "Alles fuer den Wiederlader", (everything for the reloader). They list these Lee FC dies in 5,6x61 and I think they are intended primarily for H870 users.

[Diz]

Kiwi_bloke,

Until I found this site I never had any contact with anybody that even heard of vom Hofe much less owned one so almost all the data I have I developed independently years ago. I used a "Powley computer" before I bought the QuickLoad program and had to do a lot of experimenting. Then I started making my own bullets and each step took time and effort. Now I have a RSI Pressure Trace system available to me to verify pressures and will be buying one for myself soon.

I ran some numbers using the following:

Max pressure 63,817 psi (4400 bar) CIP

77 grain Sierra Match King with the bullet specification altered to .228" diameter

Seat depth .232"

Cartridge OAL 3.050"

24" barrel

Loading H-4831SC with the above spec. yields the following CALCULATED results:

54.9 grains

94.0% loading density

3488 fps

63,391 psi

98.78% burn

20.5% efficiency

For comparison here is the same bullet etc. but with Norma MRP2 powder. Again COMPUTED!

57.77 grains

100% loading density

3470 fps

58,603 psi

98.99% burn

19.5% efficiency

I have not shot any of these yet and as always your results may vary! Keep in mind that it is a computer simulation and not hard, tested data. I will PM you and thanks for the input.

Diz

[Kiwi_bloke]

Here's a quick summary of my loading notes:

Loading to lands on this rifle is not possible because suitable bullets are almost clear of the case neck just before they touch the lands. So I take this to mean it is free-bored. As such, some of my loads produce quite different velocities to other users. I have another rifle in this calibre on the way, still being held up in Germany for permits. So it will be interesting to see how it compares.

In terms of bullet length, Nick Harvey in Sporting Shooter magazine, (Feb. 2002), advised a 5,6x61 SE owner that the original bullet measured 25mm long, (=0.984"). The 77-grain Degol bullets I have used, which were meant to be a close copy, measure 24.36mm, (0.959"). Hornady and RWS bullets in this diameter are both accurate.

I used the H870 load shown in Cartridges of the World, 5th edition. I've also seen it repeated elsewhere, though probably this is their source. I have 4 bullet types available, ranging from 70-77 grains - all .227". The velocity range using these and the same H870 load was 3,088 - 3,122 fps. The custom Lee Factory Crimp may have improved combustion and perhaps added a few more fps, but not a whole lot. By comparison, Widerladen by Friedhelm Kersting, published by DEVA, lists the same load of H870 using 77-grain Gehmann bullets at 1,025m/s (=3,362 fps).

In April 2007 I purchased Shooter's Choice bore cleaner as recommended by Wolfe's Handloader magazine to clean up H870 residue. Patches came out noticeably dirtier. However, in any over-bored cartridge, I regard getting the bore clean as very important to keep pressures down. I also wait up to 3 minutes between shots, as long as it takes for the barrel to cool and I leave the bolt open to assist this. I have used Sweets 7.62 (a strong ammonia based bore solvent), to make sure I have no signs of copper build up. Mostly now I use Boretech Eliminator to clean and Ballistol for storage.

I then came across the H4831 load data published in a now discontinued precision shooting magazine. A maximum load in my Roell-Mauser rifle produces 3,427 - 3,548 fps depending on the load combination. Gehmann did sell ammo for this rifle in Germany that was advertised as 1,060 m/s (=3,466 fps) so my 3,548 fps using a 77-grain Degol was quite acceptable to me, especially as 5 shots went under 1" @ 100yds. However the source of my loading data, Jeff Munnell, said he was getting 3,809 fps with the same load in a pre-war Christoph Funk Mauser.

I have tried different cases and primers, but this was the velocity benchmark until Hodgdon started marketing IMR powders and some fresh IMR 4350 appeared on gun-shop shelves here in New Zealand. If it every stops blowing/raining, I might see what progress can be made. I have several rifles in different calibres which have failed to meet their expected velocities by as much as 300 fps using published maximum loads. In each instance, one or two particular powders have changed everything and the fire-sale is off! I'm hoping that IMR 4350, which I purchased to use in a 8x57R 360, will do that for the Drilling and if it helps with the 5,6 too, great!

Hornady make universal seating dies that have a sliding sleeve and so I ordered one of these. However, the one meant for .22 Savage, (which uses .227" bullets), will not do the job for the vom Hofe round as the Savage has relatively thin necks. If you ask nicely, Hornady did do a small run of these for the 5,6x61 SE.

I have used factory brass only, but Jeff Munnell describes how to make suitable brass from 9,3x62 for the rimless 5,6x61 SE. The neck may need reaming however as it is 0.002" oversize.

That's about where this rifle is at so far.