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Discussion Starter #1
Am new to reloading.
Have three powders (IMR 4064, IMR, 4895 or Varget) with Sierra 168 or 175 boat tailed, ballistic tip bullets over them.

As advised I started with low weights of powder in the 36g - 39 g range depending on the book I was reading at the time and or the bullet weight.

I have two, 9 shot strings that shot very good groups with very low velocity.
I am sure that would change with increased distance.

Question is, as you add more powder what type of jumps do you consider; % increase 5-10% per loading or larger percent differences to achieve a certain velocity? In other words bracket the extremes or go step by step.

If you are confident that you can size the cartridge, put the primer in and seat the bullet appropriately is there a reason not to go to 80% of max and see how that compares to the very lowest powder weights that are advised.

Do you really learn from step by step or is it as they say, M1a should best at around 2700 fps?

thanks for the thoughts,
wfw
 

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Generally, I work in .3 grain increments for .308.

As for your powders... Starting at 36 grains is a waste of powder and bullets in my opinion. I would start at 38 grains for 3031 and 40 grains for 4895.

IMR 3031 - in LC Brass, between 39 and 40 grains is probably where you want to be for the 168...a bit higher in brass that has more capacity like Winchester Brass. For the 175... between 38.5 and 39.5 for LC Brass.


IMR 4895 - LC Brass, probably find your accuracy around 41.5 grains... start a tad lower, like 40.5 and work up 'til you hit the sweet spot for the 168 grain bullet. For the 175, start around 40.

Varget - No idea really, I've never used it for the M1A.

As for the speed bullets work best... well that depends on the bullet... but generally 2600 fps for 168's and 2550 for the 175's out of an M1a is around where you will find accuracy.
 
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