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Working up loads for 300WM
- Thread starter Six Pack
- Start date
Roadkill2228
New member
I just love the .300 win mag cartridge! I'm my particular experience, the heavier the slug, the better the groups with this cartridge. It shoots ok with lighter bullets I guess but the good stuff only happens with 180 grains and higher. Mine is a 1-10 twist which I believe most .300s are but you do hear of some in 1-11 or even 1-12 (tikka I believe). Mine really liked the 220 hornady round nose with 75 or 76 grains of rl25 for 2750 fps (long throat on mine, this might be over pressure in a tighter chambered shorter throated rifle). 7828 and 4831 powders are tried and true. Rl 22 is awesome, another great big game round I have developed is the 200 grain woodleigh weldcore protected point over 72 grains of rl22. 2900 fps. Noslers load data shows the highest velocities for their 180 grain bullets coming from imr 4831. What I'm about to start working with is the 208 hornady eld m bullet. I believe I will first play with the new imr enduron 4955 powder. Whatever you do, do not waste your time with hodgdon's/hornady Superformance powder. In every cartridge and bullet
Combo I tried, One of which was a recipe straight off the can, the shot to shot deviation was often over 100 feet per second difference.
Combo I tried, One of which was a recipe straight off the can, the shot to shot deviation was often over 100 feet per second difference.
Roadkill2228
New member
An interesting side note, the most accurate cartridge I ever whipped up was with the hornady 208 bthp (not amax) and h50bmg. I was quite new to reloading and the big powder was on a good sale so I bought it, not realizing it is waaaaaay to slow to perform well in any cartridge I load for. Nonetheless, the 208 seated out to jam in the lands and compressing over 80 grains of bmg produced amazing shot to shot velocity consistency and cloverleafed those bullets. Did about 2600 fps.
Stats Shooter
New member
6Pack,
I have a load for my savage 110 .300 win mag. It is 79 grains of H1000 using 180 grain accubonds. I was able to get 1/3" groups by moving closer to the lands. In my experience, Nosler bullets are a bit jump sensitive so moving closer should tighten that group up further. I am at work so I will have to wait until I get home to give you the exact jump but I know the load I use very well. 79 grains seems to be a sweet spot for 180 grain accubonds. I used CCI 250 Primers and remmington cases, all trimmed. The 200 grain accubond likes the exact same jump in my gun as the 180 grain accubond, but about 5 grains less powder.
I got about 3000 fps using 79 graines of H1000 in a 1:12 barrel if I remember correctly.
I have a load for my savage 110 .300 win mag. It is 79 grains of H1000 using 180 grain accubonds. I was able to get 1/3" groups by moving closer to the lands. In my experience, Nosler bullets are a bit jump sensitive so moving closer should tighten that group up further. I am at work so I will have to wait until I get home to give you the exact jump but I know the load I use very well. 79 grains seems to be a sweet spot for 180 grain accubonds. I used CCI 250 Primers and remmington cases, all trimmed. The 200 grain accubond likes the exact same jump in my gun as the 180 grain accubond, but about 5 grains less powder.
I got about 3000 fps using 79 graines of H1000 in a 1:12 barrel if I remember correctly.
Stats Shooter
New member
P.S.
Dont bother with H4831 or any of the Alliant powders using 180 gr bullets. H4831 leaves way too much space in the case resulting in high standard deviations in muzzle velocity.....and Alliant powders are too temp sensitive so if you are planning on some warm barrel target shooting with the load AND hunting, you will need two different loads.
Dont bother with H4831 or any of the Alliant powders using 180 gr bullets. H4831 leaves way too much space in the case resulting in high standard deviations in muzzle velocity.....and Alliant powders are too temp sensitive so if you are planning on some warm barrel target shooting with the load AND hunting, you will need two different loads.
Thanks to all for the good information. I appreciate the feedback.
Mississippi, as noted, the best load I've found so far is your load of 79gr of H1000. However, I am shooting it in an " Extreme Weather Model 70" with a 26" stainless barrel. I've already found the chamber to be on the high side of spec and I am limited to about 3.36 OAL by the magazine. Unfortunately, much like a Weatherby, this leaves a sizable jump of .060+. I like the rifle a lot and it seems to shoot factory loaded Accubonds fairly well (under an inch) so I'm hopeful I can recreate the performance with hand loads. I'm interested to hear what distance from the lands you found the sweet spot as Nosler told me they were designed to load .030 or more.
Mississippi, as noted, the best load I've found so far is your load of 79gr of H1000. However, I am shooting it in an " Extreme Weather Model 70" with a 26" stainless barrel. I've already found the chamber to be on the high side of spec and I am limited to about 3.36 OAL by the magazine. Unfortunately, much like a Weatherby, this leaves a sizable jump of .060+. I like the rifle a lot and it seems to shoot factory loaded Accubonds fairly well (under an inch) so I'm hopeful I can recreate the performance with hand loads. I'm interested to hear what distance from the lands you found the sweet spot as Nosler told me they were designed to load .030 or more.
Stats Shooter
New member
Six pack,
My COAL is 3.380. It is a blind staggered feed mag in my Savage 110. I actually had more room if I needed it. For me that is a jump of almost exactly 0.030. I settled there because there was no appreciable difference from .010-0.030..but as I moved back from there the groups opened up.
Btw, I also found an accuracy node near 82 grains of H1000 but the primers we flat, cratered, and one blew out so that was too hot.That was a compressed load
You might try a shorter jump and single shot it just to see the results, try the 79 grain load moving each load .005 closer to the lands. I'm willing to bet you will see the groups tighten up.
The other thing that can be done is removing some of the ballistic tip.
My COAL is 3.380. It is a blind staggered feed mag in my Savage 110. I actually had more room if I needed it. For me that is a jump of almost exactly 0.030. I settled there because there was no appreciable difference from .010-0.030..but as I moved back from there the groups opened up.
Btw, I also found an accuracy node near 82 grains of H1000 but the primers we flat, cratered, and one blew out so that was too hot.That was a compressed load
You might try a shorter jump and single shot it just to see the results, try the 79 grain load moving each load .005 closer to the lands. I'm willing to bet you will see the groups tighten up.
The other thing that can be done is removing some of the ballistic tip.
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