reloading a 300 Ultra-Mag

[idahoelkinstructor]

Can anyone tell me what are some good loads for the 300 Ultra-Mag? I want to use the Nozzler 180 gr. Acubond. Will this be a fast and accurate bullet?
Thank you for your input...

I had such high hopes for the accubond. This bullet gives me alot of flyers for some reason in my 300RUM. But here is my favorites. None are max, as I never find the most accurate at max. But all produces less than 1" groups at 100 yards for me out of a krieger barrel 26".

180gr Barnes Triple X
215M Primer
88gr RL25
3.62" COL

180gr Nosler Partition
CCI 250 Primer
93.5gr H1000
3.6" COL

190gr Matchkings
215M Primer
94gr Retumbo
3.67" COL

[marty1028]

I shoot 180 Speer Grand Slams and 180 Hornady SST. The best powder is the RL-25 or IMR 7828. The Hodgedon H-1000 didn't shoot very well for me. I am loading some 165 Barnes, hope to try them out soon.

Marty did you ever get those 180gr speers to work well? I tried 50 of them with no luck, but did all with H1000 and retumbo. I was lucky to get 3" groups at 100 yards.

[stubblejumper]

My best accuracy load in both of my 300ultramags is reloader 25 behind 180gr ballistic tips.Velocity runs 3350fps to 3375fps and groups average 1/2".180gr Accubonds group right around 1" in both rifles with the same charge of reloader 25.

[idahoelkinstructor]

I want to thank you for your replies I am new to reloading and new to computers I love this web site though. I have lived in Idaho all my life (30 years). I grew up hunting wtih my family. I am a bowhunter at heart. My wife and I also teach archery education for IDFG. Since I have been married, my in-laws have invited me every year to go elk hunting in the backcountry on horseback (general riflehunts) I have my own horse but no elk rifle so I broke down and bought a 300 ultra mag. The last bull I shot with a rifle (300 Wby.) was 10 years ago. I sold that rifle two years ago beacuse I always bowhunt (succesfully most of the time) and I have 2 kids under 3 years old. We do own a 280, It is my wife's. I was wondering though is there anyone out there who has shot bull elk with both a 300 Wby. and a 300 ultra mag, could you tell the difference between the two? I am sorry for being so long winded, just letting all of you to get to know me. I hope that is OK? I be wating for your replies. Thanks.

[oldrgr]

Evening. I have not shot a .300 Weatherby Magnum but do own a .300 RUM (Remington 700 BDL with 26 inch barrel and muzzle break).

I've gotten good results with 95 grains of H-1000 behind a 180 grain Nosler Partition. I've shot 1" groups at 100 yards. I use CCI 250 Large Rifle Magnum primers

Using the Nosler Reloading manual, 5th Edition as a guide, extracted the following data for the .300 Weatherby and .300 RUM.
180 grain bullets and max loads for all examples below.
.300 RUM
IMR 4350* 82 grains Muzzle vel. 3187 fps
RL 22 87 grains Muzzle vel. 3220 fps
H4831sc 88 grains Muzzle vel. 3205 fps
AA3100 88 grains Muzzle vel. 3206 fps
IMR 7828 89 grains Muzzle vel. 3229 fps
H1000 96 grains Muzzle vel. 3225 fps
* Most accurate load tested

.300 Weatherby
IMR4350 76 grains Muzzle vel. 3088 fps
RL19 79 grains Muzzle vel. 3198 fps
IMR4831 76 grains Muzzle vel. 3028 fps
RL22 80 grains Muzzle vel. 3132fps
AA3100 77.5 grains Muzzle vel. 3050 fps
IMR7828 84.5 grains Muzzle vel. 3185 fps
H1000 89 grains Muzzle vel. 3146 fps
H870* 92 grains Muzzle vel. 2970 fps

As you can tell the .300 RUM is a bit faster and will also have a bit more energy.

Regards

[oldrgr]

Disregard the * for most accurate load - misread the data. There was a most accurate load for each powder based on charge weight. Sorry

So stubble, what is your magic load behind 180 ballistic tips? I am guessing 95gr RL25. Is it the same load for both your 300RUM?

[marty1028]

I got the speers to shot best with IMR 7828. I need to go look but I think 88 grains of 7828 worked the best.