Those results are great, considering where you started from.
Your calculation approach will work for all bullet weights and dimensions, but be aware that your rifle barrel will have preferences for bullet shapes, bullet weights, and even powder loads. Shooting and measuring results with your rifle with different bullets, powders and powders will answer most questions you have.
The barrel twist will probably be a factor in picking bullet weight for your .22-250.
I have two .22-250s, one is a Remington 700 with a 1:14 twist purchased in 2008. A 1:14 was the traditional .22-250 twist when they first came out. It shoots bullets that are 53 grains and lighter very accurately, but loses some accuracy with 55 grain bullets. Given the age of your Rem 700, I would bet that it is a 1:14 twist.
I have newer 1:12 twist Savage that shoots 55 grain bullets very accurately. It might even shoot 60 grains pretty well, but I haven't tried them.
My rifles, barrels and my loads won't be much help, because they are for my rifles, not yours, and I find that every barrel is a bit different. That is why I laugh when shooters ask for other shooter's favorite loads because my best shooting loads probably won't be favorite loads in any other rifle.
Your calculation approach will work for all bullet weights and dimensions, but be aware that your rifle barrel will have preferences for bullet shapes, bullet weights, and even powder loads. Shooting and measuring results with your rifle with different bullets, powders and powders will answer most questions you have.
The barrel twist will probably be a factor in picking bullet weight for your .22-250.
I have two .22-250s, one is a Remington 700 with a 1:14 twist purchased in 2008. A 1:14 was the traditional .22-250 twist when they first came out. It shoots bullets that are 53 grains and lighter very accurately, but loses some accuracy with 55 grain bullets. Given the age of your Rem 700, I would bet that it is a 1:14 twist.
I have newer 1:12 twist Savage that shoots 55 grain bullets very accurately. It might even shoot 60 grains pretty well, but I haven't tried them.
My rifles, barrels and my loads won't be much help, because they are for my rifles, not yours, and I find that every barrel is a bit different. That is why I laugh when shooters ask for other shooter's favorite loads because my best shooting loads probably won't be favorite loads in any other rifle.