Assuming the same barrel lengths and both cartridges loaded to 60,000 PSI, what velocity gains do I achieve with the 6.5-06 over the 6.5 X 55 Swede?

I have the swede in a '98 mauser and am considering punching it out to the 6.5-06.

It will be very close to

V^2,6.5-06/V^2,6.5X55= case capacity-06/case capacityX55

or

velocity squared 6.5 -06 divided by velocty squared X55 equals case capacity 06 divided by case capacity x55.Ball park but close. roger

Vapo:

Roger's to complicated for me, LOL! Here's a load I use in my 6.5-06, regularly, and have taken antelope and a variety of other game. Remington brass, (I use 270 and trim), 54IMR4831/Sierra 120 Sptizer/24" barrel. Vels are 3175 to 3200fps.

Jerry

Thanks guys....copmparing the two is a bit difficult as the data for the swede is with 28" barrels often and for less than modern pressures as well.

Loads for the 6.5-06 are not easily found in common manuals

It appears as though 150 to 250'/sec increases in velocity are generated in the larger case. This is also true of the .25-06 over the .257 Roberts as well.....so it seems reasonable.

Hey Roger....is that formula for real or was you jerking my chain?...yea I havce fun here too.

There is about 150 fps differance between the 7mm-08 and the 280. Also, around 150 fps difference between the 308 and 30-06 if loaded to the same pressure. 150 fps difference is about right between teh data shown for the 260 Rem and the 6.5-06 in the Nosler manual for teh same weight bullet.

Since the 6.5x55 holds slightly more powder than a 260, you should have less than 150 fps difference between the 6.5x55 and a 6.5-06. Don't think you will see 250 fps difference at the same pressure.

Vapodog:

I just looked up the loading data for the 260 Remington in the IMR Guide, and their top velocity with a 120 grain bullet is 2895, with IMR7828. If you figure my load with IMR4831 @3195, thats a full 300 fps more. How much that means, is anyones guess, but it is still a significant increase.

By the way, Siera's 50th anniversary edition loading manual, has loading data for the 6.5-06.

Jerry

quote:

Originally posted by vapodog:
Hey Roger....is that formula for real or was you jerking my chain?...yea I havce fun here too.

no jerken, it is pure physics, No kidding. There are however some minor considerations like the powder in both must be the same, but it should be great for ball parking. It's just the basic relationship of energy content in each case.

quote:

Originally posted by vapodog:

Loads for the 6.5-06 are not easily found in common manuals

Some of the older Speer manuals have load data on the .256 Newton. That'll give you a start. Steve do you have any data? roger

i hope this is not too off topic but all i want to do with the 6.5-06 i'm trying to build is get 3000 fps with a 129 grn bullet. i don't like "pushing the envelope" as far as pressure is concerned. is this an achievable goal? or should i lower my expectations a little? thanks...bud

quote:

Originally posted by budiceale:
i hope this is not too off topic but all i want to do with the 6.5-06 i'm trying to build is get 3000 fps with a 129 grn bullet. i don't like "pushing the envelope" as far as pressure is concerned. is this an achievable goal? or should i lower my expectations a little? thanks...bud

From what I see, that is not out of the ball park...you should be able to go there.

That velocity in either caliber, in that bullet weight is more than doable. I have the 6.5x55, the 6.5x55ai, and the 6.5-06AI and all will run to 3000fps and better at reasonable pressures and good brass life. Too fast occuts near 3100fps from what my brass tells me.

I would lean toward the 6.5x55 in an 8 or 9 twist in a 5r barrel to ensure your target velocity. The 6.5-06 with slow powders and heavy bullets will make a small gain of maybe 100fps when pushed up to sane max levels. I got 3200 with a 140gr in the AI version, but brass was crapped out Keep them at 3000+/- and you will have your goal.

The 6.5x55 has lapua brass already in the box

Vapo:

I did that though a few years back... a friend had a 6.5 /06 ackley he let me play with....

after a lot of testing... I found out that if one uses a long action with the Swede and seat your bullet out to magazine length.. the difference in MV was minimal with what I considered an substantial increase in powder for the 06 case..
so was recoil....

So to be different, I went with a 257 Roberts case necked up and rebarreled a Model 70 to 6.5 x 57 with a 28 inch barrel to be an open plains rifle...with a 120 grain Sierra Match bullet I have chronographed that at 3250 fps....

however, just as Sierra's tech guys told me, the best accuracy with that bullet was going to be at 2800 fps.. and they were right, so that is what I leave it at.. 2800 fps...

2800 fps with a 140 grain bullet is no big deal at all....40grains of a lot of mid burn rate powders will give me that... 3031, 4895, 4320, RL 15, W 748....

6.5 mms don't need the extra velocity and surprisingly will penetrate more at the Lower Velocities!

I just tested a 150 grain corelokt in a 300 Mag, with an MV of only 1600 fps yesterday.... at 50 yds, it penetrated straight thru a hunk of wood about 8 inches in diameter....I was only using the wood for a back stop, not testing the penetration ability of the load.. however I was more than impressed....

so I'd go with the Swede or the 6.5 x 57.. I like necking up that Roberts case to 264 bore diameter!

cheers
seafire

Thought I might jump in with some info on the 6.5x55. I have just finished my testing a mod. 70 for a Whitetail hunt. I ended up with a 140 gameking chron'd @ 2591 to 2620. Shot two deer with that load. One was at 220 yards went through both shoulers, the other @ ~150 heart shot, small hole in and out. This is a wonderful cartridge and really surprised me with it's down range power. Good shooting, Smoker1

I've only concentrated my efforts on the 160's in my Mod 70 but I got the Sierra going 2550 with this load...

Smoker:

How's that beautiful 35 Whelen you built doing? It's been a while since we chated on Loadyourown.com.

Regards

Jerry Eden

Afraid you have the wrong Smoker Jerry Eden. I'm Smoker1, there is/was another smoker on this site when I signed on and as smoker was my handle on other various sites I didn't want to give it up, so I added the '1'. Smoker1

did I mention that this is a nonsmoking thread?????


Just kidding.

Smoker 1: Well welcome anyway. The other smoker, had built a 35 Whelen and thats how we became acquainted, we both really like the 35 Whelen.

Vapo, all my loads are smokers, except "stuff for the 338-06", LOL.

Jerry

Since the diameter of the 6.5x55 case just ahead of the rim is larger than the 30-06, I have found that, for me, the only practical cartridge to convert a strong 6.5x55 to is the 6.5-284. I don't think that I'd rechamber a pre-98 Mauser to 6.5-284, but it works well on Howa 1500s, Remington 700s, Ruger 77s, and Winchester 70s.

Jeff

Thanks for the welcome Jerry Eden, appreciate it. The 35 Whalen is a very versatile cartridge. Never owned a 35 caliber but seemed to go around it. From 30 caliber to .444. Guess there's a niche for the 35 right there! Smoker1