At Las Vegas I examined an interesting German dropblock marked 7.62x51R. Anyone have any idea what that is? Perhaps the metric designation for .30-40 Krag?

Might be for the good old 30-30wcf. Frank

Perhaps a rimmed version of the 308/307 Winchester, reasoning from the 51mm length?
Regards, Joe

The nearest factory round to that designation is the (late?) .307 Winchester, as Joe says. .30-40 would be longer, and I've never seen the metric designation actually marked on a rifle--the few continental rifles I've seen chambered for .30-40 used the inch/US terminology. All were Belgian. (Isn't the .30-30 metric designation 7.62x52R?). .307 wasn't around long enough for me to even have fired one!

Winchester cartridges retained the .30 W.C.F. designation on their headstamps and advertising up until about 1946 after which they changed their nomenclature to .30-30. Interestingly, today it's called the .30-30 Winchester but it was Marlin & U.M.C. that gave it that designation.

Over the years, it has been known as the:
.30 WINCHESTER SMOKELESS
.30 WINCHESTER
.30 W.C.F.
.30-6-100
.30 Marlin
.30-30 MARLIN SMOKELESS
.30-30 S.
.30-30 W.C.F.
.30-30 Win.
.30 American (Federal case, small primer)
DWM 543 (Germany)
7.62x51R (Europe)


copied and pasted from here
http://shootersforum.com/showthread.htm?p=52554

Well, I live and I learn (beats the alternatives). Are the metric designations of all the "30-30 family" shown as 51mm case length? (Aren't they properly the ".38-50 family" assuming that the .38-50 preceded the .38-55?).

What is the metric designation of the .30-40 Krag? Might meet up with one some time, ya never know.

Cartridges based on the .30-30 seem to be 52mm long. THe metric designation of the .22HP SAvage is 5.6x52R, I have some for my Savage 99s,. and apparently the Euros call the .25-35 the 6.5x52R, see http://gunbroker.com/Auction/ViewItem.asp?Item=121879365 and http://www.auctionarms.com/search/displayitem.cfm?itemnum=8972734
Are the .22HP and .25-35 cases longer than .30-30 cases?

mkbenenson, that's what I thought. Don't think the other .30-30 relatives are actually longer, just wonder why the difference in nomenclature. Answers probably lost in the mists of time....

Found dimension for .22HP and .30-30 (but not .25-35) at accuratereloading.com, .22HP is 2.05"/52.07mm long, .30-30 is 2.039"/51.79mm.

Found dimension for .22HP and .30-30 (but not .25-35) at accuratereloading.com, .22HP is 2.05"/52.07mm long, .30-30 is 2.039"/51.79mm.

Mark

According to "Cartridges of the World" in the Europeon Sporting Rifle Cartridges section the 7.62X51Rmm is a 30-30 Win.

They also list the 5.6X52Rmm as the 22 Savage HP and the 6.5X52Rmm as the 25-35 WCF to further muddy the waters.

I believe that the 30-30 was listed as the 7.62X51r because the Mosin cartridge was variously known as the 7.62x4r, 53r and sometimes even 52r. I have seen Finnish and Slavic sites referring to it as such, even while listing another length as a standard cartridge for issue rifles. On the other hand, Municon lists the 30-30 as both the 7.62x51r and 52r. Various French and German sites list the 30-30 as the 7.62x52r when used in drillings or combination rifles.