6.5x70 Ohlhoff

I found this on a German cartridge collector’s website. What’s the story behind this weird cartridge, the 6.5x70 Ohlhoff? What firearm shot this thing?

IAA JOURNAL #260 has an article on the cartridge and the rifle.


Since Issue 260 of the (then) ICCA Journal is from 1977, many of those reading this Forum will not have that issue, In the interests of keeping this thread complete, I will quote from a summary of an article from the Oregon National Guard Newspaper for Noember 1976 that George Hoyem did for the ICCA Bulletin:

 "The 6.5x70 mm Rimless, bearing the headstamp "D.M.  K." has been found over the years in the Northwest.  Most encountered were loaded with a round-nose solid military-style bullet which takes a magnet (JLM Note:  proper abbreviation is CNCS - Cupro-Nickel Clad Steel).  Whether they were cumpronickel (CN) clad I can't tell.  A few were made with a soft-nose hunting bullet.  The mystery of their intended arm was recently solved by the discovery in Oregon of two experimental rifles made by George N. Spencer, Forest Grove, together with a set of drawings and correspondence between him and one A. Ohlhoff, Portland, Oregon.  It appears that Spencer developed the rifles...one a bolt action with a pump-type operating lever under the forend and the other a straight-pull action... to submit for military trials.  the documents with the rifles reflect a period of 1896-1903.  The project didn't get too far, but a quantity of the ammunition was obviously produced by Deutsche Waffen u. Munitionsfabriken in their Karlsruhe plant.  Ohlhoff apparently was the backer of this project and 6.5 Ohlhoff is found in "Index by Calibre for DWM Cartridges 1896-1956" by Fadco Publishing Company, Beverly Hills, California (Fred Datig's labors), listed as the 6.5mm Ohlhoff, Portland, Oregon, with D.W.M. designated number 483.  Intriguing as this is, the same list contains a "6mm Ohlhoff, Portland, Oregon," as number 414.  As of this writing (JLM:  August 1977) I know of no 6mm Ohlhoff, similar to the long, skinny, 6.5, that has ever come to light.  (If some member has one, it would probably be similar in case shape as the 6.5 pictured here, but with a 6mm bullet.  Please let us know if such does exist.)"

Dimensions given in the ICCA Article:

Case Length 1-3/4" (70mm)
Case Diameter rim .428"
Case Diameter head .428"
Case Diameter neck .292"
Bullet Diameter .257"

“Thus, this is a true 65mm bullet. Most so designated 6.5mm cartridges are actually closer to 6.7mm (.264”), and take their metric designation, as do the 7mm family, from the land-to-land bore diameter of the rifle. The groove-to-groove diameter is .264" or there-abouts, in the 6.5 mm family."

At the time the ICCA article was written, the rifles along with their accompanying documents were in the Oregon National Guard Museum, Camp Withycombe, Clackamas, Oregon, just east of Portland.

Hope this is of some assistance and interest. Good idea to get those back issue CD’s. The back issues are full of tidbits like this. You can also get copies of the original DWM Case Number and Bullet number factory logs from Lewis Curtis’ “Gig Publications.” There is a website for them.

Here is what I have on the 6.5x70:

DWM case #483 was listed as “Kal. 6,5mm A.Ohlhoff, Portland, Ore” and no dimensions or case drawing were shown in the DWM case book. However, it has been identified as being the title for this 6.5x70 case (ref Buttweiler).

This rare experimental cartridge was manufactured by DWM for Ohlhoff of Portland Oregon (USA). This case was designed as a rimless .25 calibre version of the 22 Krag M95 Experimental for an experimental George.N. Spencer magazine rifle. A. Ohlhoff was in the hardware/firearms business in Portland and served as an agent for the manufacture of the cartridges with DMK. As he could not find any U.S. manufacturer for this round, he therefore turned to DMK-DWM for manufacture.

Evidently, Spencer and Ohlhoff had a small firearms workshop in Portland, Oregon. They specialised in the development of HV cartidges from around 1895 to at least 1902 including rimless 6.5mm and 5.6mm versions of .22 Krag M95 Experimental, which were made in very small quantities by DWM. This calibre may have been intended for US Military trials (as c1896 was DWM #425 6mm USN rimmed, #425A 6mm USN rimless, #425E 6mm USN and possibly the 6x56 American Luger - see M10).

The date of production is confusing. DWM case #483 is c1902 but all known specimens have the DM-K hs "DM * K * " which is generally <1897. This hs has been used by DWM after its formation in 1896 particularly if earlier DM-K cases were used. If this was the case here, then which cases were used is not known.

Note also that the DWM case book does not list DWM case #414 as a “6mm Ohlhoff, Portland, Oregon,” but rather a 6mm Mauser Revolver. There is no 6mm Ohlhoff as far as I can tell.

WBD, The earliest 9x19mm cartridges are headstamped DM * K * and we know that they were produced no earlier than 1902, so the it is not surprising that DWM #483 also had a DM * K * headstamp.

Like Tony Edward’s thread on 7x57 suggests, the headstamps seem to outlive the changes in company names.

Cheers and thanks for your interesting posts.

The initials “D.M.” were used on military 7.9 x 57mm ammunition made by DWM all through WWI, as late as 1918.

Lew is is right on about some headstamps living beyond name changes.

I note Brad’s comments about the DWM entry 414 not being related to an Ohlhoff cartridge. I have the DWM book in question, from Datig, published by FADCO, and Brad is absolutely right. Further, a quick look through (no time for a careful search right now) did not find any entry for a 6mm Ohlhoff. While I was simply quoting the ICCA Bullet 260 article, I probably should have checked my book and verified if the information was correct. A comment that it was not would have been in order on my part. Sorry about that.

I wonder how George Hoyem, or the Newsletter quoted, got that information into their material. I can’t speak for the Oregon National Guard editors of their newsletter of the time, but Geroge is usually a very careful researcher.

John, there is no need to apologise as it was quite clear you were quoting from a previous article. Fred Datigs book (like all of our books) has errors which with time we slowly eliminate. I have looked through all my DWM references and have no idea where George got that case #414 reference.

I mentioned the “D.M * K *” hs as further evidence of the DWM use of this hs after DM-K became DWM and as Lew stated the 9mm Para is the best known eg. Similarly “Lorenz” hs were apparently used after Lorenz became “DM-K”. The same is true for other German companies eg the “M&W SOEMMERDA” hs. Sure makes it hard for us to research introduction dates …


I hate to make the topic even more confusing but the two rifles that are associated are not chambered for the 6.5x70 cartridge. In fact they are not chambered for any cartridge at all. Both rifles have wooden mock barrels. There is only the assumption that they are supposed to be chambered for this cartridge because several rounds along with a few other items accompanied the rifles when they were given to the museum.

There is little published information on this obscure cartridge and much of it is extrapolated speculation. I can state with near metaphysical certitude that Ohlhoff was not in the firearms/hardware business. He was a civil engineer for the City of Portland.

The cartridge is of interest to me because if its association with the State of Oregon. Since it has come up, I suppose I should hurry up and update the historical recordin the IAA.

Dave McKay

Dave - hope you can do something to set the record straight. I was just responding to the request about Issue 260 of the ICCA Journal. It seems that virtually all of the information in that article is wrong! Am kind of sorry that I put it on the Forum now, as I realize now that the whole article just muddies the waters completely about this cartridge. The picture in the original article was so poor that the guns in it were not much more than outlines - impossible to see any detail of the actions, much less that they had wooden barrels! I don’t know anything at all about sporting rifle cartridges, so I couldn’t originally judge the article at all.

Sorry my effort just led to confusion. I should have tried to do my own research, but I am working very hard on a book right now.