There has been a lot of confusion over this fine old Savage round over the years. Ken Waters, in a Pet Loads article, says the early guns appear to have had bore dimensions of .303 grooves and .311 lands. To stabilize the early load featuring a 195-grain bullet, twist rate was 1:10.
At some point, Savage went to a .300/.308 barrel, and some sources say, a 1:12 twist. Waters' own rifle, SN 43,898, had a .300/.308 barrel with 1:10 twist. He recommended owners of earlier rifles to slug their bores and measure twist.
Those of you with 99s in .303, have you slugged your bores and checked twist rates?

How do I know which one is mine?
Meant year and all that Bill?

Boarkiller, my take is that if yours was built after serial number 43,898, it most definitely is .300/.308, but I can't tell you which twist you'll have. I would think the faster 1:10.
If yours predates that serial number, you might want to slug the bore to see if it is .308 or .311. Thanks for the response.

I'll check my twist rate, but I cant remember whether I have any lead around to slug the bore. I also have no idea when the N.O.S. barrel I got of Ebay was made.

I repeatedly checked my twist rate using the tight patch/cleaning rod method and came up with 1-12. That kind of surprises me, but the 190 gr. bullet was relatively short. I still would have thought they would all have been
1-10. Can't argue with the facts though, and Ken Waters is one writer that really does his homework!

Lee, is your barrel accurate?

My 303 is 311,1:10 it seems, figure built some time in around 1907.
Shoots great for a old lever gun.
Of course can't hold a candle to a new Remington 700 7MM08.

Al

Thanks for the intel, Yooper. You ever get tired o' that old .303, let me know.