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Author Topic: 12.7x44R calibre designation  (Read 3581 times)

29. December 2011 kl. 20:40:42
Read 3581 times

Jan van Gelderen

On 31 august 2007 Mr Flatnes published the folling explantion about Swedish/Norwegian rolling block cartridge lengths:

44 and 42 are cartridge lengths in millimetres, and they are often followed by an R for rimfire. The reason why both 44 and 42 is used is this: In 1879 Norway adopted a new bullet, and as a result the point of impact changed. Because of the cost of altering the sights it was decided to increase the powder charge slightly to compensate for trajectory of the new heavier bullet. The increased powder charge in turn resulted in a 2 mm increase of the case length. It is a common misconception that the new Norwegian round couldn't be fired in the Swedish rifles. Nothing was done to the chambers, and the Swedish and Norwegian rifles had similar chambers from the start.

OK, that sounds clear to me. I put it in a table to make it brief:

Calibre designation  |   Remarks
12.17x42R (RF)...........Swedish/Norwegian military round
12.17x44R (RF)...........Norway chose to increase the powder of the load
12.7x44R (CF).............Swedish (and Norwegian?) Volunteers round

What I do not understand is that the centre fire volunteers round is designated as 12.7x44R. Why is it not designated as 12.17x44R?

29. December 2011 kl. 21:16:58
Reply #1

Øyvind F.

The Norwegian army never used 12.7, 12.17, 12x44, 12.7x44, 12.17x44 or the other similar designations. The military cartridge was simply designated 12 mm Remington (from 1879). Before that, it was simply called 4''' (4 linjer). Nothing else!

Regarding "12.17", this is the nominal bore diameter of the rifles, and originally it was never stamped on civilian centrefire cartridges. 12x44 and other designations were used. So as a rule of thumb, loose the "17" from all designations. Some manufacturers used "12x42" others "12x44", and I think some even used 12.7x44 or 42.
Øyvind F. - forum admin
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