284 Win, Case capacity

[jesilva]

Can anyone tell me what the case capacity difference is between Norma 284 brass and Lapua 6.5-284 brass necked up to straight 284. I would like this information to see if Lapua brass will yield more velocity than the Norma brass I am currently using.

Thanks

 

[ShootDots]

Can anyone tell me what the case capacity difference is between Norma 284 brass and Lapua 6.5-284 brass necked up to straight 284. I would like this information to see if Lapua brass will yield more velocity than the Norma brass I am currently using.

Thanks

I can not tell you what the "water / alcohol" weight volume is between the 2. However, what I can tell you is, is that the actual powder loads are virtually the same. I have shooting friends that have "straight" .284's as well as .284 Shehanes and use the new Norma as well necked up Lapua brass. The loads with both H4350 and H4831SC using 180gr. bullets, are all within a few tenths of a grain of each other. So if there is somewhat of a difference in the "water / alcohol" weight, it does not show up in powder / load development capacity, or the velocity of either.

 

[Jimcor]

I can not tell you what the "water / alcohol" weight volume is between the 2. However, what I can tell you is, is that the actual powder loads are virtually the same. I have shooting friends that have "straight" .284's as well as .284 Shehanes and use the new Norma as well necked up Lapua brass. The loads with both H4350 and H4831SC using 180gr. bullets, are all within a few tenths of a grain of each other. So if there is somewhat of a difference in the "water / alcohol" weight, it does not show up in powder / load development capacity, or the velocity of either.

If for use with QLoad you will need "fired" capacity which might vary very slightly depending on chamber size. If it helps I am getting 67.1 grains H2O with Lapua and 67.9 grains H2O with Norma. I agree with ShootDots that this doesn't seem to make much difference in practical terms.

 

[jesilva]

Thanks

 

[1shot]

If you look at Shehane articles and reamer prints, the say that the Shehane is 3.35gr. more than the straight 284. (66.00 vs. 69.35 gr.) QL calls the 284 at 66.0gr. but my measurements for three fired Lapua cases averages 68.83 gr. of pure H2o at room temp. for the Shehane.
I hope this helps,
Lloyd