Compressed loads with long bullets

[Koda]

So I loaded some and tried the shake down method. Saw another version of it, by taking a tray that holds the brass, load the charge (I did 3, CFE 223, A2520, Varget), then put another tray upside down, on top to hold everything in place. Laid on an oscillator tool for 5 seconds or so.

This used max Hornady load data on a 129g SST.

All shook down so there was no more compression when seating the bullet. Shake down was in the range of .040 to .060.

I am going to the range in the next day.

So, with this shake down, would it be considered compression? We are certainly removing the small gaps.

At least, I have refrained from crunching the power when loading the round.

Thanks for the feedback.

excellent news, .04-.06 is significant and eliminated compression. Im glad this worked for you.

IMO, no, vibration is more of a consolidation to me but not a compression, basically a more efficient use of space like a well played game of Tetris. After you seat the bullet, handling the round will re-disperse the powder around the bullet but there is no pressure on the bullet.
Compression breaks apart the powder granules with force making some of them more compact and leaves pressure on the bullet, Ive heard they can push it back out over time.