Thread: Trying something, Eric Cortina method of load development

So with my model 70 270win I decided to have a crack.
Out of curiosity I measured the distance to the lands with a hornady OAL gauge and got an average length of 2.780" which would normally see me seating at 2.760 for my seating depth.
Using the Cortina method I got 2.840"
My maximum mag length allowed for a max ogive length 2.7605
So in keeping this able to be mag fed I started at 2.760"
I loaded all my charge weight ladder at this length going up in .5gn increments.
I'm using superformance for something different so started at 55.5gn through to 57.5gn
I shot them today with surprising results.



Great velocity and consistency at 56.5gn and then at 57.5gn the velocity was incredible for a 270win case but I was getting very slight ejector swipe.
I have no doubt my max load could be tuned but i don't want to be anywhere near pressure.
I am going to now load up a seating depth ladder at 56.5gn and shoot them at paper to see what accuracy is like.
It was really strange shooting the charge weight ladder over the chrono without a target but I'm really keen to see how the seating depth tunes the load.
Either way 3040fps avg is fair humming for a 145gn eldx and more than enough for a good hunting round