What gives with modern 6.5x55 loading data?

[Wild Bill G]

Was just looking at 6.5x55 loading data compared to 260 Rem. The 6.5x55 has a larger case by a few grains of water but the 260 loaded to the same load produces over 100fps more velocity. The barrel difference is 1 inch in favor of the 260.
Is the Sweedish cartrage a weak case desing like the 30-30 because even loads for new guns appear mild. The old Speer manual load showed a load of 50grns. of 4831 push a 120 grain bullet. The new manual showss a loading for a modern strong action rifle using about 45grns. of 4831. That should say Imr 4831 but why the decrease with a strong action. My way of looking at is that 2 rifles one in 260 and one 6.5x55 both winchesters should produce equal velocity. That is with everything being equal. However loading manuals give the nod to the 260 as I said by over 100fps. Some of my reasearch here used the new Nosler manual and some the new Speer. Both said they were loads for modern strong action 6.5's. Any thoughts or things I have missed.

 

[Mikecr]

In general, a larger capacity cartridge would need more powder to match a smaller cartridge.
The larger case is simply less confining for a given amount of powder. But, you can put more powder in the larger case. More, slower powder, for heavier bullets.

It all begins with a bullet. If you were to compare the two with 123gr bullets, the 260 would win.
For 140gr bullets the swede wins.

Don't get too caught up in factory loads, or in manual suggested. Ask around (as you are) & review loads over at reloaders nest: 6.5x55 Mauser @ www.reloadersnest.com

 

[Wild Bill G]

I figured the Swede could put more powder in the case being larger. However the difference in case capacity is only 4 grains of water. That would not be enough to make a huge differnce would it?

 

[Mikecr]

This is a reloading edge(similar to twist rate for 22cal/90gr VLDs)..
The advantage to 26cal is it's heavy for cal bullets (139-142gr). The 260Rem just lacks capacity to drive them at the best accuracy node (2950-3000fps). That is, 260 brass won't survive that node in the long run. Either 260AI or 6.5x55 will, and do all that's good with 26cal.
If Lapua had recognized this(it's been known elsewhere forever), and offered 260AI brass, sales there would soon reach that of their 6.5x47. Oh well....

It's my understanding that published 6.5x55 loads are so conservative because it's associated with Mausers. But there is no downside about a 6.5x55 that I can think of in a modern firearm.

 

[pineywoods]

It seems the pressure limitations are a bit conservative with the Swedes. I have two 700 classics in 6.5 x 55 & I can go a good deal above published max in either rifle without seeing pressure signs... & with one exception they shoot best loaded hotter than the manuals allow. I'm sure there are others with similar experiences...

 

[Wild Bill G]

Please keep feeding in the info I will be unable to respond for 2 weeks at least. As I am going in for a pancrease transplant in the mourning.
I look forward to reading any further input when I get back Cheers.

 

[Gene]

It's my understanding that published 6.5x55 loads are so conservative because it's associated with Mausers. But there is no downside about a 6.5x55 that I can think of in a modern firearm.

Exactly the correct answer to the OP question. Also, reloading manuals differ; they are only a guide.

Love my sporterized Swede; have shot many deer with it using Norma brass, 139 gr. Hornadys, and H4831.

 

[tbrice23]

Please keep feeding in the info I will be unable to respond for 2 weeks at least. As I am going in for a pancrease transplant in the mourning.
I look forward to reading any further input when I get back Cheers.

Good luck brother. Hope to hear from you soon.

 

[Jerry M]

Norwegian 6.5x55 Krags have one locking lug like all Kregs. Obviously loaded to the lowest pressure. As stated above, in a suitable action the cartridge can be loaded a lot hotter.

At least three shooters I know are using this cartridge with a different shoulder angle for 1000 yard F-class with great results. Loaded hotter than book levels.

Good luck

Jerry

 

[Deleted member 118518]

I have a Mauser 98 large ring with a 24.5" McGowan #3 barrel that shoots the Hornady 129 gr interlock at 2915 fps with 48.6 grs of IMR-4831. The load groups 5/8" three shots at 100 yds. from sand bags. There is no heavy bolt lift or smeared brass on the case head and the primers are not cratered and they maintain their rounded edge. The barrel chamber was hand finished so that as the bolt closes you can feel a very slight snug feeling at the end. That aspect combined with controlled round feed keeps the case head back against the bolt face where it belongs. Upon reloading the case trimmer makes one to two revolutions and it is done. So neck stretch is very minimal and case life is long. My first deer season with it resulted in three deer with the range being between 340 to 385 yards from the short shot to the long shot and one bullet each. Two does and one 9 pointer a bit over 200 lbs. I knew where I would be seeing deer and the scope was set at zero on 300 Yards. Yes, the action was blueprinted. The Hornadys did a great job as did the rifle and cartridge. I love that 6.5X55 SE cartridge. It was easy to find a load and bullet that it liked and I also load a .260 Remington in a 700 BDL with 24" BBl with the 129 and have not yet been able to match velocity of the 6.5 Swede. It runs about 100 fps behind the other cartridge. The case is Hornady and I use the Fed 210 primers. Not that I can be trusted with a calculator but my extrapolations from known loads and pressure readings indicate a chamber pressure of 46,635 CUP. Again that is a best guess.

 

[Carlos88]

Exactly the correct answer to the OP question. Also, reloading manuals differ; they are only a guide.

Love my sporterized Swede; have shot many deer with it using Norma brass, 139 gr. Hornadys, and H4831.

To be "technically" correct it's the <'98 Mausers produced eons ago. Lots still around.

Ruger, Winchester, Remington, commercial Mausers (Mark X, Santa Barbara, Browning, Husqvarna >'96, 1910-1936, 1954 Mexican mausers can be "souped" up a bit more. I've had about every iteration I just mentioned. It's a great caliber. Mostly shot 129gr Hornady's and 120 TSXs.

Lotsa fun.

 

[Carlos88]

I have a Mauser 98 large ring with a 24.5" McGowan #3 barrel that shoots the Hornady 129 gr interlock at 2915 fps with 48.6 grs of IMR-4831. The load groups 5/8" three shots at 100 yds. from sand bags. There is no heavy bolt lift or smeared brass on the case head and the primers are not cratered and they maintain their rounded edge. The barrel chamber was hand finished so that as the bolt closes you can feel a very slight snug feeling at the end. That aspect combined with controlled round feed keeps the case head back against the bolt face where it belongs. Upon reloading the case trimmer makes one to two revolutions and it is done. So neck stretch is very minimal and case life is long. My first deer season with it resulted in three deer with the range being between 340 to 385 yards from the short shot to the long shot and one bullet each. Two does and one 9 pointer a bit over 200 lbs. I knew where I would be seeing deer and the scope was set at zero on 300 Yards. Yes, the action was blueprinted. The Hornadys did a great job as did the rifle and cartridge. I love that 6.5X55 SE cartridge. It was easy to find a load and bullet that it liked and I also load a .260 Remington in a 700 BDL with 24" BBl with the 129 and have not yet been able to match velocity of the 6.5 Swede. It runs about 100 fps behind the other cartridge. The case is Hornady and I use the Fed 210 primers. Not that I can be trusted with a calculator but my extrapolations from known loads and pressure readings indicate a chamber pressure of 46,635 CUP. Again that is a best guess.

Spot on.

 

[Deleted member 118518]

This is a reloading edge(similar to twist rate for 22cal/90gr VLDs)..
The advantage to 26cal is it's heavy for cal bullets (139-142gr). The 260Rem just lacks capacity to drive them at the best accuracy node (2950-3000fps). That is, 260 brass won't survive that node in the long run. Either 260AI or 6.5x55 will, and do all that's good with 26cal.
If Lapua had recognized this(it's been known elsewhere forever), and offered 260AI brass, sales there would soon reach that of their 6.5x47. Oh well....

It's my understanding that published 6.5x55 loads are so conservative because it's associated with Mausers. But there is no downside about a 6.5x55 that I can think of in a modern firearm.

Mikecr I agree with you info. If I may add to it a little. The swedish military wanted a single cartridge for their infantry rifle plus their machine gun. The end result of this was the 6.5X55 cartridge. It was first chambered in the 1894 small ring Mauser then later it was used in the 1896 small ring. These actions were great but they cock on closing not cock on opening as in the large ring 1898. The small ring actions were limited to 46,000 as a proof charge with standard issue ammo loaded to considerably less with a 156 grain round nose I believe. The strength of the small ring actions was the fly in the ointment that has stuck with what is an excellent cartridge. And keep in mind that the machine gun would be affected by any change to the 6.5 as adopted and would cause possible problems with it which would mean more expense so as a result nothing changed. But when the Mod 98 came along it had more muscle around the barrel and was chambered for the 8x57 which routinely operated at 49,000 cup or higher. People think nothing of taking that action and rebarreling it for 30/06 and filling it full IMR 4350 and slaying whatever with it. So to say that the Swede is getting short changed is an understatement. The fact that the reality of this is not better know nowadays is amazing. A Remington 700 or savage 110 or Ruger 77 can turn the old war horse into a great performer and with the bullet selection we currently enjoy it is a do all cartridge except for large bruins. Handloading is the key and the knowledge of what to look for by conscientious riflemen will keep one alive for a long time.

 

[cdherman]

But its a pain for 6.5x55 lovers to always have to basically exceed the book numbers. I have a nice old M94 and a modern Tikka T3lite in 6.5x55. The modern Tikka gets its own brass, own loads of course. But I have to basically throw all the book loads out of the window. I use Quickload and I am just fixxing to try a new load in the Tikka, which should easily blow past the 260 and 6.5 Creed. But no book would ever have printed it......

Also, to be clear! An old 120 yo Mauser action is NOT as strong as a modern action. Yes, as much as Karl was a genius, modern metalurgy is far better than the best he could get his hands on. You CANNOT safely load an old Mauser to the same pressures. You may not get signs of pressure on the brass, before the gun itself blows......