Handloading 6.5x55: More Velocity!

[vriesmana]

Hello,

As we all know, the 6.5x55 Mauser is a classy Scandinavian babe of a cartridge. Used for deer, moose, elk, target shooting and even on the battlefield. Last year I got my hands on a Sako 85 bolt action in this world-class chambering.

My handloads consist of Lapua brass, 44.5 grains of IMR 4831 and a Sierra Gameking bullet. This is listed in the Nosler 5th edition manual as a MAX load for the 6.5x55 Swedish Mauser. Recently, my friend offered to chronograph me. I was excited to see the results, especially since the Nosler manual shows 2760 fps in a 23" Wiseman test barrel from this load.

We set up the Caldwell about 10 feet from the muzzle. Fired five shots, then read the chronograph numbers. A lazy but consistent 2550 fps! Roughly 200 fps below the book.

I realize that my 22.5" barrel is 1.5" shorter than the Nosler test barrel. But still, 200 fps slower? Perhaps it's my powder. Or the chronograph. Maybe my Sako was built on a Monday. It might be the fact that we set up the chronograph ten feet from the muzzle. We were also at 4000 feet elevation with low humidity and a temperature of 60 degrees F.

In further reading, I found an article by John Barnsness about velocity. This is a good read:

http://gunsmagazine.com/velocity-myths-vs-facts/

Now my question. Will switching to a powder like Vihtavuori N560 or Reloader 22 help me get higher velocities out of my rifle? I'd love to go buy some more powder, but I thought I'd ask first. Especially since the Viht is over $40 per pound. That's more expensive than line caught salmon at Whole Foods.

Thanks for your replies.

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[Jamie6.5]

You don't say what bullet weight this load is for, but I'll assume you mean a 140gr.
FYI,... Hodgdon's data website lists a heavier Max load for IMR 4831/140gr than Nosler does, but roughly the same velocity results @2700.

Do you have any pressure signs?

ETA: I ask this because Hodgdon's website shows pressure maxes well below that of most modern firearms. These are all configured based on being used in the old Swede rifles. You should have room for more, just keep a close eye out for pressure signs in the fired brass.

Are you loading it to Nosler's recommended COAL?

 

[vriesmana]

Thanks Jamie, to be clear this is for a 140 grain load. No flattened primers, sticky extraction or other signs of pressure. And no, I'm not using Nosler's recco'd COAL. I'm loading the bullets a little bit further out because this Sako has got the rifling so far out there.

 

[Jamie6.5]

Thanks Jamie, to be clear this is for a 140 grain load. No flattened primers, sticky extraction or other signs of pressure. And no, I'm not using Nosler's recco'd COAL. I'm loading the bullets a little bit further out because this Sako has got the rifling so far out there.

As long as the mag length allows it, and the throat/freebore allows it, I've pushed bullets way out, so that shouldn't be a factor. Just don't jam them. I like to start about .080 off the lands with hunting rounds so I've got a little room to move either in or out for fine tuning a load.

I would head over to the Hodgdon site and grab their recipe. Shoot a few and then check again for pressure signs and proceed.

 

[akmewon]

fwiw my 18 inch ar vs my 16 inch ar have about 200 fps difference with same load.

 

[vriesmana]

Jamie, do you find that seating the rounds further out helps? I will be sure to check out Hodgdon's load for the 6.5x55. I think you can actually push this round pretty fast if you're not using a Swedish Mauser or a Krag.

As for the powder question, anyone use Vihtavuori N560? I read that powder is "boosted" with nitroglycerine and can help increase your velocity without undue pressure. I'm not an engineer, so I'm not sure how that works. Like I said, $42 a pound and imported from Finland.

 

[Jamie6.5]

Jamie, do you find that seating the rounds further out helps? I will be sure to check out Hodgdon's load for the 6.5x55. I think you can actually push this round pretty fast if you're not using a Swedish Mauser or a Krag.

As for the powder question, anyone use Vihtavuori N560? I read that powder is "boosted" with nitroglycerine and can help increase your velocity without undue pressure. I'm not an engineer, so I'm not sure how that works. Like I said, $42 a pound and imported from Finland.

If you can bump them out far enough to gain some powder room and not get pressure signs I might try it. My .270 loads are over book max, but my COALs are are way over too, and still off the lands by quite a bit even with 150 gr bullets. And I did get my velocities up past factory ammo by almost 100fps or so.

But if you seriously want to gain some velocity, I would go with an Ackley Improved chamber. It did wonders or my 6.5x57, and keeps pressures reasonable.

I've avoided the Vhit 500 series powders because I read years ago that it's kinda hard on barrels. Most of my gun's barrels have enough freebore, I don't want to accelerate throat erosion.

 

[Member 5605]

Thanks Jamie, to be clear this is for a 140 grain load. No flattened primers, sticky extraction or other signs of pressure. And no, I'm not using Nosler's recco'd COAL. I'm loading the bullets a little bit further out because this Sako has got the rifling so far out there.

Further out means less case volume which means slower bullet. More powder burns and has more volume to expand into prior to pushing bullet down the barrel.

I had an experience where once I loaded out .020" off lands I ended up with 1.5gr over published max before I ran into sticky extraction. 1.5gr more gave me same velocity as mag length with less powder.


Check out the powder burn chart. Find a powder with a published load that burns faster with your 'shorter' barrel.

 

[U8395279]

Jamie, do you find that seating the rounds further out helps? I will be sure to check out Hodgdon's load for the 6.5x55. I think you can actually push this round pretty fast if you're not using a Swedish Mauser or a Krag.

As for the powder question, anyone use Vihtavuori N560? I read that powder is "boosted" with nitroglycerine and can help increase your velocity without undue pressure. I'm not an engineer, so I'm not sure how that works. Like I said, $42 a pound and imported from Finland.

N560 is indeed one of the powders that i have seen recommended on reloading websites for the 6.5x55mm Swede. Other powders that I have seen handloaders recommend are RL 22 and IMR 4350.

Vihta Vuori is quoting a max load velocity of 2,770 fps using N560 and a 140 gr Sierra and a 26 1/2 inch barrel:

6,5 x 55 Swedish Mauser - Rifle reloading - Reloading Data - Vihtavuori

In the Alliant Powders Guide, they recommend RL 19 for 120 gr bullets, and RL 23 for 140 gr:

http://www.alliantpowder.com/resources/alliant/2016_Alliant_Powder.pdf


If one wants to use one powder for both bullet weights, then RL 22 seems to be best suited for doing that.

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