300wsm F-Class - Seating Depth Test at 800 metres - Please read description

Testing of my new 300wsm barrel is going well. Today I tested at 800 metres for seating depth. Please refer to the following specifics of the test:

Weather conditions:
Temperature: 20 degrees Celsius
Humidity: 70%
Wind direction: South/South East (left to right cross with switching tail)
Wind Speed: 10kmph

Rifle Specifics:

Rifle Stock: Cerus XR
Action: Borden BRMXD, left bolt, right port, left eject
Scope: March HM 10-60x56
Trigger: Sidhe Evo Benchrest
Barrel: Brux 9 twist finished at 32"
Tuner: Dan Bramley

Ammunition:

Projectile: Berger 220gr LR hybrid
Brass: ADG 300wsm
Primer: RWS large rifle primer
Powder: ADI 2209 (H4350) - 60.9gr
Velocity: 2815fps average (no pressure signs)

Breakdown of shots and seating depth:

Shots 1-6 - 10 thou jam into the lands
Shots 7-11 - 15 thou jump off the lands
Shots 12-15 - 40 thou

The clear winner from this test was the 15 thou jump which produced straight X's. Conditions were reasonable with the wind being a bit flicky but the condition was there if you could read it - sight picture was ok.

Rifle tracking was good - whilst the 300wsm produces more recoil than the 284/7SAUM cartridges, in this setup it's fine to shoot and entirely manageable.