Gentlemen:
My Rasch combination gun (Büchsflinte) from the 1920s is chambered for .25-35 Winchester (besides 16g), which in Europe is usually named 6,5x52R.
Dear Jani, 16 years and 7 months have passed since you started this thread, and I am glad to have retrieved it via the site's search function. It proved to be rather fruitful to me, since I recently acquired a nice and elegant Schonzeitdrilling / Niederwilddrilling chamered in 24 gauge / 24 gauge / 6,5x52R, which was probably made in the beginning of the 20th Century (Bügelverschluss or Rouxverschluss, two bites / underlugs and a Doll's head). Might have been sourced from Greifelt one of the various Merkels, don't know.
And I marvel at the thread's development, and am amused by the sometimes rather robust and spirited style of discussion and opinion (or opionatedness, as one may wish to see it). Nonetheless, the discutants, even when remaining opponents, did not become enemies, as it appears. It is different today in the times of Europe being under combined attack by the Neo-Czarist Empire and by the Viertes Reich, yonder from the opposite direction... bad times we live in.
What astounded me at times while perusing the discussion, was the tunnel vision, indeed a very studiously and emotionally upheld tunnel vision of some the discutants, instead of purposely taking two or three steps back, and re-adjust the eyes from myopia to normal sight. And pausing to take off the blinkers; those are for carriage horses.
1. For some time, "the" cartridge (I shall deal with the tricky definite article later) was called [.]25-35 also by the firearms producers, dealers and gunsmiths in German-speaking Central Europe. Not so by proof houses and ammo firms, maybe. You have very wisely cited Mahrholdt as an authority, because he was maybe the widest-read and best-informed of all Germanic writers in his time. When he changed his employed primary denomination, he must either have been yielding to an already impending trend, or have been setting the new trend himself.
2. My suspicion - and only a suspicion it is, as of yet - would be that the European ammunition manufacturers were the first ones to designate "the" cartridge with its metric nomenclature, and that gunmakers and gunsmiths only followed suit quite a bit later. I am sure the ammunition collectors community with their collective wealth of old catalogues could help us here, but the IAA forum so far does seem not offer much. Maybe I have not sleuthed it properly.
3. It is a commonly expected and encountered recommendation that the "two cartridges" be not exchanged, or more specifically, only into one direction, not into the other. However, the minuscule differences between CIP and SAAMI, with their cartridge case and chamber dimension data will usually (!) not impede the use of one cartridge in a gun nominally chambered for the "other". Especially not in a rimmed cartridge like this / these.
4. Today, the CIP data tables list "the" 6,5x52R and "the" .25-35 Winchester separately and with separate nominal (= normative) maximum pressure limits. Also, the differently conceived and differently measured SAAMI pressure data "appear" higher than the CIP. However, there is no strict and reliable conversion factor, only a rough rule of thumb. The conversion factor itself also definitely depends upon the propellants used in the case (semi-pun intended).
5. The myopic fixation upon the nominal maximal use pressure does lead us away; very *far* away even. Into the swamp.
6. What counts, is the ACTUAL and measured, real-life pressure of the cartridges at hand. And that one may be far, far away (far more than the commonly expected "20 % safety factor") from the max use pressure.
For a long time, there was only stubborn ignorance of the Real World ('"But Aristoteles hath decreed thus in his sacred writings, and hence it must so be - and no, I shall NOT look at he animal in question; if he wrote horns, it must have horns !" *child stomps foot on ground*). Then, many years later after this thread, a German hunter actually submitted real modern cartridges to one of the German proof offices, and found out that the real pressure of the modern .25-35 was still clearly
lower than the maximally allowed pressure of the 6,5x52R (as now made by Sellier & Bellot). And hence quite safe. The pertinent thread is to be found in the German "Jagd und Wald" hunting forum. Imagine !
7. This does NOT mean, does not allow the conclusion that in the past, other American .25-35 loadings may not have been hotter than the present US version now appears to be. This is not impossible, of course, since US manufacturers in the not-so-litigious past did offer Hi-Vel loads of various cartridges. Notorious were the examples of the rifle loads for the .32-20 and the .38-40, much discounselled for revolvers.
8. I just got possession of a small stash of different old 6,5x52R factory cartridges by "RWS", "RWS." (yes, the dot has some meaning, but I do not recall it at this moment), "N" and DWM. Were this lot larger, I would be tempted to have some of them tested by a proof office here but they usually want at least three cartridges.
I have not yet found the 'RWS "Schonzeitladung" with a very light bullet and light powder load, which must have been notoriously weaker.
Regards and Weidmannsheil,
Carcano
