Safe Loads and Max Pressure in my Norwegian Krag?

[Drachenblut]

Hello,

I reload for 6.5X55 Swedish Mauser, primarily for the Swede rifles. A Norwegian Krag has recently come into my hands, and I want to reload for it using Winchester 760 Ball powder, behind a 140 grain Hornady SP bullet. However... I looked online and in a manual of mine. The lowest pressure they list is 40,000 CUP on the Hogdon Reloading Data Center for 37.5grn

Now, I know that one has to be delicate with these rifles/carbines (mine is a wood sporterized but original barrel length, matching 1912 Carbine), meaning not to exceed 40,000 PSI. After some research I determined that CUP has no correlation to PSI.

Before I attempt to reload for it, I am looking for some absolutely safe loads for my Norskie Krag using Winchester 760 and H335 Powder. Can anyone recommend some please? Also, what is the max pressure you would load for, in both CUP and PSI?

As an aside, I also am curious to the max CUP and PSI ratings for Swede rifles previous to 1910 (I have an 1898 dated one).

Thanks,
Drach

 

[Goldenlakepete]

My Lee Second Edition manual has a starter listing of 36.3 grs of W760 with a 140 gr bullet. A MAX load of 39.6 grs for 44100 CUP.

I couldn't find a listing for H335 and the 6.5x55.

 

[Drachenblut]

Great. A load of 36.0grn of Win760 and a 140 grain bullet would work very well and keep pressures low.

Thanks! Anyone else?

 

[Goldenlakepete]

I looked through all my books and magazines and the only reference I found to loading for the Norwegian Krag was in the 12th Edition of The Handloader's Digest. Unfortunately most of the loads the author listed were for obsolete powders like H-570 and N-205. He did have one load for the Krag with a current powder - 45 grs of H4831 with a 156 gr or 140 gr bullet. I question this because according to the Lee Manual that is a fairly stiff load.

 

[Drachenblut]

Thanks. I loaded 50 rounds with a load of 36.0grn of Win760 and a 140grain Hornady SP bullet. I'm using Herder's Brass and Win. Large Rifle Primers. Cartridge Overall Length of 3.055

We shall see how those work next trip to the range!

 

[Drachenblut]

Are there any other good, low pressure loads you gents can recommend?

 

[bigedp51]

If you Google your question "Safe Loads and Max Pressure in my Norwegian Krag?" you will find a Krag Collectors Association Forum and they recommend keeping your loads at or below 40,000 psi.

If you go to the Hodgdon's website the start load data falls into that pressure category.

Also note that when working up a load and starting at the recommended start load the primers will back out of the primer pocket. As you increase the load generally at the mid-point of the load data you will see the primers starting to be flush with the rear of the case.

As long as the primers are protruding and backing out of the primer pocket the bolt thrust or pressure on the bolt is very low. When the primers are flush with the rear of the case the chamber pressure has reached the point that the brass case is stretching to meet the bolt face. At this point the bolt thrust starts to increase and apply more pressure to the bolt face.

Bottom line, my 30-30 Winchester primers are always protruding at 38,000 -40,000 cup and NOT applying any force to the locking lugs.

Below, watch the primer back out of the primer pockets below, as long as the primer is protruding VERY LITTLE force is being applied to the bolt face.

 

[Drachenblut]

Excellent, just the information I was looking for. Much appreciated.