Are they basically the same case capacity/ Can I use .30-30 data for the .303? Just acquired a n older, very nice 99 Savage with 60 rounds of ammo, and Lee dies will be here in a couple days.

Yes

Yes, .30-30 data is A-ok to use in this instance. Case capacity is nearly identical. As with all recommendations, start low and work up.

Contrary to old wives tales, .303's use .308 diameter bullets, and any bullet suitable for the .30-30 is good for the .303. (In the first couple years of the .303's life they were loaded with .311 bullets but bores were always .308. The extra pressure entailed in that combo was thought to give it a slight advantage over the competitor's .30-30. Whether id did or not, or was viable, is open to debate, and at any rate Savage abandoned that folderol very quickly.)

Factory loads for the .303 always used either 190 (Winchester, Western, U.S.Cartridge Co., Savage, etc.) or 180 grain bullets (Rem-UMC, Peters, Remington, etc.), again to give it that little bit of extra punch over a .30-30. Just use 150 or 170 grain bullets and live it up. The Savage with its rotary magazine is usable with spitzer bullets that are a no-no in a tubular magazine Winchester or Marlin. (Try them too, but beware of possible performance issues re: reliable expansion at greatly reduced velocities than what some of them are designed for.) Crimping isn't necessarily a needed thing with a Savage also. I never crimp loads intended for a Savage lever gun.

Thanks, guys. You confirmed my suspicions. As to spit zeros, I have 125 & 150gr Sierras and some 165gr Hornadys. Thinking the lighter weights would be a bit better, especially the 125s. Loaded some down with H4895 for a friend's son's .30/06, and he's managed to kill 3 deer in two years, the buck dressing out at 163#.

Saw a 2 part box of 182 grain... Remington(?) bullets down at Tulsa that I pointed out to Rick.

The 1900 Savage Arms catalog featured 180gr and 185gr regular ammuniton.

There was a LOT more variety to the early 303 Savage ammunition that is normally given credit for. But I agree that 180gr and 190gr were the most prevalent and 190gr won out in most of the later commercial loads.

Used a Hornady 150gr FN a few years ago in a 1920 1899A in 303 Savage to bag a small buck for the freezer. Never took a step, just fell over sideways.

See, this thread is why I laugh at people that say I have too many posts.

Lyman Reloading Handbook #43 has 303 Savage loading date on page 59.

Here are some loads for 150 grain jacketed bullets;

4198, starting at 24.0 grains and maximum at 27.0 grains.
4895, starting at 30.0 grains and maximum at 35.0 grains.
3031, starting at 30.0 grains and maximum at 32.0 grains.
4064, starting at 31.0 grains and maximum at 34.0 grains.

Here are some loads for 170 & 180 grain jacketed bullets;

4895, starting at 31.0 grains and maximum at 34.0 grains.
3031, starting at 28.0 grains and maximum at 31.0 grains.
4064, starting at 30.0 grains and maximum at 33.0 grains.

Here are some loads for 190 grain jacketed bullets;

4895, starting at 30.0 grains and maximum at 33.0 grains.
3031, starting at 28.0 grains and maximum at 31.0 grains.
4064, starting at 30.0 grains and maximum at 32.0 grains.

Here are some 30-30 loads to compare to the 303 Savage;

150 grain jacketed bullet with 3031, 30.0 grains to start and 33.0 grains maximum.

170 grain jacketed bullet with 3031, 27.0 grains to start and 31.0 grains maximum.

Thanks, Remguy. Was thinking about RL15 instead of 4064, but I have that, too.

Perhaps those were the preferred propellant options when #43 was copyrighted in 1964.

Good point.

I've shot deer with 125gr .308 Ballistic Tips at ~2300 fps starting velocity, and they expanded and killed well. It would be easy to exceed that in a 1899, without straining things.

With 303 loading data available in several books and on Hodgdon's site WHY would you use data for a 30-30?

Close only counts for horseshoes and hand grenades

Because there's a LOT more .30-30 data available, for a wider variety of bullets.

When I had my last .303, I compared the water capacity of fired Winchester-brand brass in both cases, as I recall with 170-grain Hornady Interlocks seated to the cannelure. Capacity was IDENTICAL, down to a tenth of a grain. And if case capacity is identical, then basically pressures and velocities are too, given the same bullets and powders.

This is true regardless of case shape, no matter what some claim. No pressure lab anywhere has been able to find differences in shoulder angle, case length, etc. Pressures and velocities may be more consistent due to case shape, but not average pressure and velocity. And the .30-30 and .303 are very similar in case shape.

That's interesting, Mule Deer. Most information I've been able to dig up shows the 303 Savage case being between 2% and 5% more capacity. But I've never measured both cases like that.

Appreciate the info.

Perhaps too verbose.

He does have a way with words. Marcel Marceau's got nothing on him!

Tremeloes

He's at his best when he says nothing at all.

That's probably worth repeating.

Thanks for this, John.

Looks like that would be a YES.

They are pretty much the same and I have shot them both extensively over the years. My old Savage .303 will shoot very well with the Sierra 170 FN bullets but throws everything else into a pretty big pattern. I suppose that makes mine XACTLY like a .30-30.