by tomtom889 » 14 May 2020, 12:41 pm
Hey mate, I reload Barnes TTSX projectiles for my .338 Win Mag, I myself was also concerned about pressure do to the projectile being solid copper instead of lead core.
I emailed ADI reloading support about the load I wanted to put through my rifle and this was their response:
Unfortunately we do not have any test load data for .338 Winchester Magnum with 225
grain Barnes TTSX projectiles. Monolithic solid copper projectiles, such as the Barnes
do create more bore resistance due to their harder construction than lead core
projectiles. As a result chamber pressures for any given projectile weight and
propellant charge weight are generally higher for the solid projectile compared to a lead
core projectile.
As a rule of thumb you can calculate the starting/maximum charge weight for a Barnes
or any other solid copper projectile by reducing the charge weight for a same weight
lead core projectile by 4%.
For example, you can refer to the test data generated with 225 grain Hornady SP
projectiles, which are lead core jacketed projectiles and reduce the charge weight by
4%. This means that your starting weight using the 225 grain Barnes and AR2209
would be 60.4gr.
The Cartridge Overall Length of 3.340” used to generate the data with the 225 grain
Hornady SP projectiles is at the Maximum SAAMI Cartridge Overall Length for this
cartridge.
TL;DR, if you have an ADI loading manual, reduce your min/max safe loads by about 4% for a given-weight projectile.
Happy and safe reloading!