Been trying some norma brass in my 270 wsm. Although the ID of the neck after sizing and the neck thickness is pretty well the same as the R-P brass the pressure it takes to seat the same bullets is noticeable more with the norma brass. I got a feeling this increase in neck tension is leading to some accuracy issues.

Any comments?

In my experience, absolutely! The R-P brass is as hard as it gets (not necessarily a good thing) and the Norma brass is just about as soft as it gets (not necessarily a bad thing). As you re-size and re-size brass, it work hardens and when it's hard to begin with, you may lose cases prematurely if you don't anneal them. With Norma, as long as you don't exceed SAAMI specs on your reloads, they should go a lot longer before they need annealing. Somebody else may have a different take on this but, this has been my experience over 48 years of reloading.

why then do I seem to be getting more neck tension with the norma brass?

Softer brass will tend to grab the bullet more while the harder brass will allow the bullet to glide into place..

[quote]Softer brass will tend to grab the bullet more while the harder brass will allow the bullet to glide into place.

ok that makes sense. What can I do about the harder seating that I think is resulting in more neck tension?

My example of one was with 22-250 brass and the Norma brass seemed considerably softer than RP. In short order, I was getting split necks and loose primer pockets with a load the RP brass had handled with aplomb.

I think that you will get more "springback" from the harder RP brass than from the softer Norma brass - this could be why your bullets are seating tighter with your Norma brass.
After I anneal my brass, I always use a bushing 0.001" larger for the first time reload, thereafter I resort back to normal bushing size.

here is my experience with norma brass in 22-250, I could not get the stuff to have enough neck tension to hold any of my bullets enough, I even tried using a different make of die, the only thing I could get to work was a bushing die, which caused more runout, so I switched back to win brass