6.5-270 (257) Wby Mag...What do I need?

[Longtooth32]

I really think Weatherby should have introduced the 6.5 Wby Mag in the 257,(6.5) ,270 and 7mm Weatherby line of cartridges a while back, it would be a great cartridge and a little bit more sensible than the 6.5-300. jmho though.

I have to agree with you...I expect to get over 3400fps with the 140s and over 3300fps with the 150s...

 

[tbrice23]

Check your freebore. My PacNor 270wby does not have .375" standard wby freebore that I was hoping for .

 

[Longtooth32]

Check your freebore. My PacNor 270wby does not have .375" standard wby freebore as I was expecting.

I checked when I ordered the barrel...

What freebore did you get with your 270Wby?

I will check the freebore when my barrel arrives...

 

[tbrice23]

Haven't measured it but here's my SST to the lands compared to your SST at mag length.

 

[tbrice23]

However, the barrel shoots, here's a moderate charge of H1000 fireforming load with 150 Ballistic tips at 193 yards

 

[Longtooth32]

However, the barrel shoots, here's a moderate charge of H1000 fireforming load with 150 Ballistic tips at 193 yardsView attachment 100534

Nice shooting...!

My Fireforming load is 77gr H1000 @ 3.4" COAL with the 150 SSTs...3350fps

The only problem you may have is if you shoot the 165 Matrix. I can jam them into the throat with my .378" freebore.

If you are shooting the 170 Bergers..I am about .3" off the lands @ a COAL of around 3.5"...

Are you going to add a little more throat to your barrel?

 

[tbrice23]

Not immediately.
The 170 gr EOL seated to the lands has the bearing surface/ boatail junction at the start of the neck/shoulder junction . Which gives me about 77 gr of RL33 without compression.

 

[Longtooth32]

Not immediately.
The 170 gr EOL seated to the lands has the bearing surface/ boatail junction at the start of the neck/shoulder junction . Which gives me about 77 gr of RL33 without compression.

Are you going to try any RL26?

 

[tbrice23]

Yes and Retumbo. I think I will load some 26 with the 170s next time out.
The barrel is 100 rounds broken in and haven't shot any of the intended bullets yet.

 

[tbrice23]

Just checked capacity with RL26, 75.5 gr. I'll work up to that.
This is with virgin brass.

 

[Longtooth32]

Yes and Retumbo. I think I will load some 26 with the 170s next time out.
The barrel is 100 rounds broken in and haven't shot any of the intended bullets yet.

I fooled around with IMR 7828ssc, Retumbo, H1000, MagPro... settled on RL26. ES<10 fps on a 10 shot string. 72 grs @ 3.5" COAL, 170 Berger, 3225fps, 28", Russian Mag primer, with my "stock" Wby throat...

Have fun...

 

[Longtooth32]

Just checked capacity with RL26, 75.5 gr. I'll work up to that.
This is with virgin brass.View attachment 100541

I would be curious to see what kind of speed that you will get out of the RL26...

 

[tbrice23]

I'll make a report in a new thread so I won't keep de-railing this thread, lol.

 

[tbrice23]

Just found this if

Anyone is interested .