LVLAaron
Gold $$ Contributor
That load is simply too hot for the conditions for several reasons. First, you're trying to hit the high node with the 200.20X bullet and Varget. In Lapua Palma brass, that means pressures predicted to be well above SAAMI max for a .308, probably in the 63-64K psi range, or even higher. According to the folks at Alpha Munitions, their SRP brass has an average water capacity of 54.8 gr, which is more than a full grain lower than Lapua brass runs on average. Add in the elevated temps and excessively large firing pin hole on a Savage rifle, and what you observed shouldn't be too surprising. If you dial that load back to the 2640-2660 fps node for that brass/powder/bullet combination, it may not be necessary to have the firing pin hole bushed immediately, even though it's probably a good idea to have it done anyhow. Typical Varget charge weights to hit the lower node with Lapua brass and the 200.20X usually end up somewhere in the 43.2 to 43.6 gr range.
FWIW I measure Lapua to be 56.15 (fired) and Alpha SRP to be 55.49 (fired)