270WSM Load Data question…

[Shampy]

Hi, all,
I’ve got a box of 150gr Norma Oryx bullets for my Browning X-Bolt in 270WSM that I want to develop a hunting load for, but information is pretty much nonexistent. I’ve not really run into this issue before. Been reloading my own ammo for many years and always had data for the components on hand. Looking to use IMR 4350
I started thinking that I could use data from a 150gr Partition and start at min and go from there… but the Oryx seems like it might have a bit longer bearing surface than the Partition. Anyone else run into a similar situation? Looking for advice, not load recipes
Thanks in advance!

Shampy

 

[RegionRat]

I agree, that bullet has a long bearing length compared to others.
I would try not to jump to far in the work up and watch to see how it compares to other versions with published data.
If I got it to roughly 3000 without issues, I would be happy.
Were you thinking of starting around 52?

 

[Shampy]

I agree, that bullet has a long bearing length compared to others.
I would try not to jump to far in the work up and watch to see how it compares to other versions with published data.
If I got it to roughly 3000 without issues, I would be happy.
Were you thinking of starting around 52?

I was thinking right around that. 52-ish grains of IMR4350. Nosler lists 53 grains as the starting point with the 160 Partition, 54 grains with the 150. I’m thinking 52-53 would be a sane start. With a long pull cord

 

[RegionRat]

Here is the Norma 150 and the Hornady 150
Both have a similar base design and bearing lengths.

I would chart the data for the Hornady 150 with H4350 and keep it with me while I did the ladder testing. You would see if there was a great offset either higher or lower, but I think you have a good chance of staying safe if they track. It might look something like this:

Good Luck and in for the range report.

 

[Shampy]

View attachment 8236294View attachment 8236296

Here is the Norma 150 and the Hornady 150
Both have a similar base design and bearing lengths.

I would chart the data for the Hornady 150 with H4350 and keep it with me while I did the ladder testing. You would see if there was a great offset either higher or lower, but I think you have a good chance of staying safe if they track. It might look something like this:
View attachment 8236317
Good Luck and in for the range report.

Thank you, RegionRat! This is good stuff. I’ll keep some notes and check back with what I come up with. This seems to be a fair sanity check, though. Thanks again
-Shampy