Slickest, the best solution is, one to use a PAST RECOIL PAD when your shooting this .300 mag at the bench, it's cost is around $38 dollars. The other is to have the end of the barrel slotted by Mag-Na-Port and company. They do a great job and you won't even notice those small little slots in the end of the barrel. Now this will take about 10 to 12 percent of the recoil off that .300 mag and also it will remove the muzzle jump as well. I have done this to several rifles over the last 30 years of so and it works like a charm and half the cost of having an ugly "muzzle brake" installed on your rifle..........heavens NO!
Mag-Na-Ported rifles are a Remington 700 heavy barrel in .375H&H, model 70 heavy barrel in .457 cal, model 70 .458 Win mag, model 70 stainless in 7mm magnum. All of these rifles became much easyier to shoot! The 7mm mag's muzzle jump was all but eliminated, it shoots like a .243 Winchester from the bench.