6.5x55 blows primer?

[roysclockgun]

The first round blew out the primer, so I quit shooting, pulled the bullets and dumped the propellant back into the can.
My question is: can anyone shed light on what might have gone wrong?
Rifle; Swede Model 1896 sporter, 6.5x55mm, through which I have put several hundred rounds with no indications of too high pressures, using other loads.
Bullet; Speer 120 gr. HCSP that I intended to use this year on deer. I checked the weight of the bullets and they are correct at 120gr.
Brass; once fire PMC that I had full length resized and trimmed.
Propellant: H380 that has a recommended max load of 49gr. with the 120gr bullet. I had loaded to 47.5gr.
Other propellants have grouped well. If I decide to again try H380, how far down should I drop the load?
It is always unnerving to hear of signs of too high pressures, but worse to personally experience an incident.
Any responses appreciated.
Steven

 

[onesonek]

My Hodgdon manual shows 44.3 grs. /H380 as max. I'm guessing you are running near 52-53000 cup at 47.5, maybe more. It's always good to check a new load with 2 or more scources. With older firearms or ones I don't know well, I always start with the lowest load listed til I know whats what. But always double check the source with new loads!

Dave

 

[DrMike]

Steven,

It is indeed unnerving when a primer blows. There are any of a number of reasons why a rifle could blow a primer. It is a good practice to work up any load in a new rifle or if even one component has been changed. A couple of questions may help in suggesting what might have happened. Was the primer pierced? Or did it actually back out of the primer pocket?

 

[roysclockgun]

I have not found the primer.
The source for the load was the "Lyman 47th/Reloading Handbook". Page 235 shows the load for "6.5x55mm Swedish Mauser". "120 gr. Jacketed Spitzer". "H380". "Suggested Starting Grains" at 44.0 for a velocity of 2597 fps. "Max. Load Grains" 49.0 for velocity of 2890.
Realizing that my load of 47.5 gr. was too hot, by virtue of the blown primer, I certainly will not use that load again. However, this manual has always provided me with safe loads and starting out at 1 1/2 grains below the suggested max. does not appear to unsafe in any other load that I have worked up.
Steven

 

[Antelope_Sniper]

In my experience, 49gr a H4831 behind a 120gr bullet is a max load in the ol Sweed. 47.5gr of H380 would be scarry hot, and a blown primer would not suprise me. Hodgdon's #26 suggests 41 grains as a starting load, and 44 grains as a max load. Considering your recent experience, I'd say 41gr would be a good place to start and work up from.

 

[1Shot]

You need to take it easy with the 96 Swede action rifles and not go over 46,000 cup. The Lyman 48th manual does not even list H-380 powder with 120 gr bullets. Sierra 4th edition list 45.8 grs H-380 as the Max load for 120 gr bullets.

I have always had great accuracy and velocity with 46 grs Accurate Arms 4350 and the 120 gr Ballistic tip or the Sierra. From the 29" barrel of my sporter 96 Swede it get 3000 fps with this load.

I called and talked to the people at Accurate Arms and the ballistics guy gave me this load and said it was a max load for the Swede 96 action but it was the one that he used.

46 grs AA 4350, Fed. 210M Primer, 120 Nosler ballistic tip, Rem case, OAL 3.050

This is very accurate and will smoke a deer .

 

[R Flowers]

I am sure that when Lyman tested the loads that are in the 47th edition of their manual that the data they printed was valid. As someone else mentioned, they do not even list H380 in the 48th editionwith 120 grain bullets. I just checked and they do not list H380 for 120 grain bullets in the 49th edition, either.

H380 is like a lot of other ball powders in that the lot to lot variations are just terrible. Not just with this cartridge/bullet combination. Look at several manuals and you will see wild differences in maximum loads listed for H380. Again, for the powder lot tested, the data was probably valid.

I would think H380 would be a pretty "fast" powder for use in the Swede, anyway. Try slower burninig powders.

I personally just simply will not use ball powders in rifles anymore. (though I admit to burning lots of H110 in my magnum revolvers)