Your rifle, scope and range finder are a good combination.
The drops at range seem a bit on the steep side.
Sierra match kings don't have the best of BCs.
Give the barrel a good cleaning removing all copper residue then try some RL-22, CCI-200
primers and 130 Nosler Ballistic Tips. Start the powder weights in the low 50s, sneak up maybe 0.5gr at a time. You may be getting near max by 56 or 57 grains.
If you have no pressure problems with 60gr of IMR 4831 you should be good to "maybe" 58 of RL-22. If so, and she's accurate, those bullet drops down range will drop significantly.
Be care on the pressures though.
PS: What's this Sir stuff.