doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com (OT) 6,2mm/52 marked old German double

Gentlemen:
My Rasch combination gun (Büchsflinte) from the 1920s is chambered for .25-35 Winchester (besides 16g), which in Europe is usualy named 6,5x52R. But this one is marked 6,2mm/52 on the barrel flat. Why is that? My guess is this is land diameter of the rifled bore, or maybe bore diameter before rifling, but would need a confirmation. The reason is I have trouble registering this gun as the caliber on invoice (6,5mm) is different from the marking on the barrel flat (6,2mm).
With kind regards,
Jani

I suspect the original European nomenclature for the .25-35 Winchester is incorrect.
Here in Canada when we reload a 25 calibre rifle cartridge (250-3000 Savage, 25-06 Remington, examples), we use .257" diameter bullets.
When we reload a 6.5MM rifle cartridge (260 Remington, 6.5x55 Swedish Mauser, examples), we use .264" diameter bullets.
These bullets match very closely the groove diameter of the barrel, not the bore diameter.
The British are the main "offenders" in this area, naming their cartridges using the bore/land to land dimension in the cartridge name. Thus their .303 British cartridge uses a .311" bullet, while their .275 Rigby (aka 7x57 Mauser) used a .284" diameter bullet.
Hope this helps.

The marking of the German proof house indicated the "Bore" dia, rifling not included & length of chamber. It was not marked as to whether the cartridge was rimmed or not. As to the caliber 6.5mm = .256" which is approximate bore dia foe the .264" bullets. It is actually very close to actual bullet dia for the .25's IE .257". I understand the .25-35Win round became quite popular in Germany for use in drillings & combo guns, they apparently took the liberty of calling it the 6.5x52R as a play on the popularity of 6.5mm rounds throught Europe, there were few actual .25 caliber rounds produced there.

I'll have to check, but I believe there to be marked difference in the 0.25-35 Winchester and the 6.5X52R. I don't even think 6.5X52R will chamber in a 0.25-35, but I for one would definitely not ignite a 6.5X52R in a 0.25-35 after having it reamed, theoretically, that is.(Rand added)

Kind Regards,

Raimey
rse

We should not mix another cartridge here, 6.5x52 Rimless (6.5 Italian Carcano) which is military and something else entirely. But 6.5x52R (as made by Norma, RWS, S&B) and .25-35 Winchester are one and the same thing, which is confirmed by all standard references starting from Cartridges of the World. My rifle will chamber both of these rimmed cartridges normaly.
With kind regards,
Jani

Jani:

First, let's deal with this one:



God, no. I don't know how you've gotten so mixed up, but you're badly misinformed. I assume that you're actually referring to physical dimensions, which are indeed close. I'm not surprised that a .25/.35 cartridge will fit in your rifle, and that's unfortunate. The 6.5X52R and .25/.35 Winchester are NOT the same cartridge and are NOT interchangeable, nor does anyone intend them to be. The assumption that they "are one and the same thing" IS dangerous.

From your description of the markings, it certainly sounds like your rifle is a 6.5X52R. Unless the maker actually marked it ".25/.35" somewhere, it isn't a .25/.35.

CIP specifications for both are here:

http://www.intermin.fi/intermin/images.nsf/files/B0E765375DA00143C2256FBE0032DD2A/$file/TABIIcal.pdf

For ease of review, just print pages 12 and 58. As you can see, dimensions are very close, but certainly not identical, and it's clear that they're not intended to be interchangeable.

The fatal difference is in the standard pressures. CIP Max Average Pressure (pmax) for the 6.5X52R is 2,450 BAR/35,534 PSI. CIP mandates that official proof ammunition produce a mean pressure of 125% of MAP (pmax X 125% = PE: proof pressure). Thus, CIP proof ammunition for 6.5X52R must produce 3,060 BAR/44,382 PSI. A new rifle must survive only two of these bombs to pass proof. CIP pmax - Maximum Average Pressure for STANDARD AMMUNITION - for .25/.35 Winchester is 3,050 BAR/44,236 PSI. CIP standard .25/.35 ammunition is PROOF AMMUNITION when fired in a 6.5X52R! Especially since yours is a drop-down barrel action, that would be a grave error, and unequivocally unsafe.

Perhaps you understood this, but it sounded like you didn't, so I thought it best to clarify the difference. Now, to your original question.



I'm surprised you're having that problem in Europe, as there are so many European rifles floating around from those days with caliber designations in the proof marks that don't match the nomenclature of the round. Yes, in those days, the 6.2mm referred to bore (land) diameter, not groove. The difference between the two is usually about .012", or rifling .006" deep. For example, "6.5mm" (.256" bullet), marked "6.2mm" (.244" bore) = .012" of diameter is rifling. Think of all the 8X57J rifles marked "7.8mmX57" at the proof house - .318" bullet vs .307" (7.8mm) bore = .011". The S bores at the time were marked "7.92mm" - .323 bullet vs .311 (7.92mm) bore = .012". The 9.3X74R rifles were marked "9mm" at the proof house (.366" bullet vs .354" (9mm) bore = .012". This is nothing if not common. I would have assumed that your authorities would be familiar with it.

I'd suggest getting in contact with the proof house in Hannover - maybe your G. L. Rasch was proved there since it's the closest one to Braunschweig. At any rate, if you send them photos of the proofs, they should be able to explain the matter to the satisfaction of your authorities.

Good luck.

Whoa, whoa, whao; typo on my part. Let me correct this above/previous post with a "R" for rand!!!!

400 NE: did this get you off that "Hussey" thread? You appear to be spot on as the differnce in pressure is what I was attempting to infer.

Kind Regards,

Raimey
rse

400 Nitro Express:
Thank you for your warning, etc., much appreciated. I received this gun from Germany last week and have not yet researched the matter so deeply. So now I understand that .25-35 Winchester and 6.5x52R are not considered the same, at least not by CIP.
But I still dare to think that these two cartridges WERE considered one and the same thing in the times when my Rasch was made (1920s). I have access to a few catalogs of well known Austrian gun companies of the period and therein they are quite obviously considered one and the same thing. One example: In 1927 catalog of Tiroler Waffenfabrik Johann Peterlongo Innsbruck there stands "25-35 Winchester (6,5x52mm)". (At that time R for rimmed cartridges was not yet commonly used in Austria). By the way, the cartridge illustrated in marked "25-35 Velo".
With kind regards,
Jani

The longarm probably passed thru Suhl or Zella-Mehlis as the I think the Hannover facility didn't come online until 1952 or 1968(higher probability).

I wonder what the pressure/data was for the black powder 25-35? Is "Velo" stamp on the tube? For some reason I had the 25-35 & 6.5X52R reversed in my mind as far as pressure.

Kind Regards,

Raimey
rse

Jani,

Interesting bit. It makes me wonder if the "25-35 Velo" was a proprietary cartridge from Galand. Galand had basically trademarked the Velo Dog pistol. He was French but made his guns in Belgium. He had showrooms in a number of cities. There is little recorded about many of the Belgian and French proprietary cartridges.

http://www.littlegun.be/arme%20belge/artisans%20identifies%20g/a%20galand%20gb.htm



Pete