Just bought a pound. Never tried it before. Have been loading the 200 grain LRX from Barnes in my 300 WIN MAG using Ramshot Magnum with good success but thought I would try RL33 for the heck of it. Anyone know its burn rate relative to Ram Mag? Anyone with load data?

Try Alliant web site. Web site indicates that RL33 is primarily for the 338 Lapua. If you got one, load up and go.

I did a bit of testing today in my 300 Win Mag: 25" barrel with long throat. Loaded rounds with 200 LRX are 3.515" long which puts it 0.060" off the lands. Sierra 220 SMK is 0.005" off lands at similar COAL but did not measure. I used Win cases and F215 primer.

So here are my chrono results with 200 LRX:
82 grains= 2910 fps
83 grains=2960 fps
83.5 grains=2990 fps
All were compressed charges. I used a drop tube and then used the Lee Factory Crimp Die to help keep the bullet in place.

220 Sierra Matchking (coated with something called Acculube- do not remember the company that coated them)
80 grains= 2830 fps
81 grains=2890 fps
82 grains=2880 fps

I am getting 2930 fps with 79.0 grains of Ramshot Magnum so RL33 is obviously slower than it. Overall it is clear that RL33 is really too slow for the 300 Win Mag using 200 grain and lighter bullets but I will probably do a bit more testing for accuracy with the 83.5 grain charge. Pressure did not seem at all excessive with all charges tried.

My experiences with RL-33 leads me to believe it works best with the heavier bullets for any given caliber.

Have had excellent accuracy with high velocity with following:

257 weatherby 110 accubonds higher beat retumbo max load
6mm-284 105 Berger hybrid beat Retumbo max load
300 RUM 230 gr Berger hybrid large vel gain over H-1000
7mm/375 Ruger 180 Berger hybrid didn't try other powders

I tried RL33 some more today with the 200 grain Nosler Partition.

86 grains=3029
86.5 grains=3049 and 3077

In my rifle these loads seem safe. Bolt lift/extraction seemed normal and there were no shiny marks on the case head. Bullet was seated to 0.030" off the lands which came out to be 3.500" overall length.

Did a bit more shooting today with RL33 in my 300 Win Mag. Today I tried the Nosler 200 Accubond. 86.0 grains was a compressed load. 12 shots averaged 3030 fps. Accuracy looks promising.

Previous loads with rl33 and accubond had bullet at 0.015 to 0.040" off the lands. At 15 and 30 off had two shots touching with third out giving 0.8 and 0.9 inch groups. Today I tried 5 thou off and decided to shoot prone with bipod and sling. Got a nice triangular group of 0.59" so am pretty stoked. 200 Accubond at 3030 with great accuracy.

Great velocity.

I just picked up a pound to try in the 264WM with the 140's, and after seeing this, may give it a run with the heavies in the 300

Can't find it on a burn rate chart, but looks like it may be right around H-870?

Has the same technology as RL-17 giving a longer burn and more time under the pressure curve.

Interesting. I have a Ruger #1 in .300 mag, with 26" barrel and a long throat. I can seat 180 Nosler BT's well past 3.60". It has liked Reloader 22 in the past, but I have been planning to try R25 and Retumbo. R33 may be worth a look, too.

Not RL-33 data, but just got back from trying H-1000 with the 200 grain Sierra GK. Shot a ladder from 75 grains to 79.3

Velocity was amazing. Enough so that I won't be using RL-33 in the .300.

Nice node at 78.4, 78.7 and 79 at 3100 fps. Lower velocity node at 75.7, 76, 76.3 was over 2900.

Will report back with .264 Win Mag results though...

rcamuglia, how long is your barrel on your 300? That velocity is quite surprising.

26"

Best load today was 78.1 grains and only MOA at 200. Right around 3000.

I think that's all this rifle is capable of.

I think I have finalized my load for my 300 Win Mag using RL33 and the Nosler 200 Accubond. As mentioned before I had great accuracy with the Barnes 200 LRX at 2930 fps using Ramshot Magnum but thought I would try this new powder and see if I could get more velocity but still at safe pressures. The Barnes is longer and I could not get as much powder in the case as I could with the Accubond. I think I will settle on 86.0 grains using the Federal 215 primer and Winchester cases behind the accubond. I am getting 3030 fps. I shot a 0.59" group at 100 yards prone with my bipod and sling and followed that up with a 0.35" group (both 3 shot groups) from the bench.

From the bench:



Prone with bipod and sling:

Rufous,

Thanks for sharing your data.

As a side note I use RL-33 in a 300 RUM with 230 gr berger hybrids. Barrel is 24" and was a 300 win mag till I rechambered it as an experiment. It was my 5th do it yourself machining job. Using 100 gr of RL-33 velocity is 2975 fps. 8 3/4 lb rifle's results brings tears to my eyes.....or is it the recoil? <grin>

AZ-what action are you using? I may eventually go to a 300 RUM. Did you try other powders with the 230 Hybrid?

87.5 grains of RL33 gave me 3160 fps with a 175 Barnes LRX and Fed 215 primer.