Powder recommendations for 300 Norma Magnum shooting the Berger 230 gr Hybrid OTM Tactical Rifle Bullet.

[Bruce K]

Powder recommendations for 300 Norma Magnum shooting the Berger 230 gr Hybrid OTM Tactical Rifle Bullet. Users have recommended RL33, N570, Retumbo and H1000 out of a 27 inch barrel.

My Quickload queries suggest N570 and Retumbo have burn rates where the propellant is burn at or close to 100% at the muzzle. Others showed to be slightly faster including N568 by a very narrow margin.

Asking Google AI Search the following “Between RL33, N570, H1000 and retumbo which is the better powder for the 300 norma magnum shooting the Berger 230 gr Hybrid OTM Tactical Rifle Bullet” they came up with N570 or Retumbo.

Below is the Google response. What have you folks found to be your powder of preference?

Response

For a 300 Norma Magnum with a 230 gr Berger OTM, N570 and Retumbo are the best powder choices, with N570 offering potentially higher velocity and good temperature stability, while Retumbo provides excellent accuracy and case fill. RL33 can achieve high velocities but is known to be less temperature stable, and H1000 is a great powder for accuracy but may not reach top velocities for this heavy bullet. Ultimately, the best powder will depend on your specific rifle, and testing both N570 and Retumbo is recommended to determine the optimal load,

Key Powder Considerations

N570:

A strong contender, N570 provides high velocity and good accuracy with heavy bullets, along with good temperature stability. It is a popular choice for both speed and consistency,

Retumbo:

Retumbo is known for producing excellent groups and provides good accuracy for the 230 gr Berger OTM at moderate velocities. It also helps ensure good case fill,

RL33:

While RL33 can achieve velocities over 3000 fps, it is considered more temperature sensitive and can be harder on barrels,

H1000:

H1000 delivers great accuracy and is a reliable choice, but it typically results in lower velocities compared to other powders with this heavy bullet, potentially not reaching the ideal "accuracy node" for speed,
Recommendations

Start with N570 or Retumbo:

These two powders are generally considered the best performers for this specific bullet in the 300 Norma Magnum,

Consider Your Priorities:

If maximum velocity and temperature stability are your main goals, prioritize N570. If peak accuracy and good consistency at a high case fill are your focus. Retumbo is a great option,

 

[rustyinbend]

My go-to load for this is ...

... gives me single-digit SD's and hits mile-targets without breaking a sweat.

 

[Matt_3479]

I’m running n570 with 230’s at 3000-3050fps. I have a little more room in the tank and had them just over 3100 with 570 and 3150 with rl33 but rl33 wasn’t as stable and 570 shot best here

 

[RegionRat]

@Matt_3479 Beautiful rig and very nice shooting!

That's roughly 3600 ft*lbs worth of energy in that load!

Those are very tight groups and it is rare to see any sort of rig that can do this. Well Done!

What does your rig weigh?

 

[Bruce K]

Thank you gentlemen for your information. I was originally going with N570 which produces good results for many, but as a double-base powder (it uses nitro-cellulose with added nitroglycerine) for increase energy, but with it come heat and consistent reported cases of accelerated barrel (throat) erosion.

In my early investigations so far, H1000 and Retumbo are producing good results at slighly slower velocities. I have a supply of H1000 and Retumbo seems out of stock everywhere I've looked. I also was able to find Federal 215 Gold Medal Match Magnum primers. I'm going to start wtih the Berger 230 gr Hybrid OTM Tactical bullet and then try the Berger 245 gr Hybrid target bullet.

My Accurancy International AXSR arrived at my FFL dealer a few days ago and I'm gathering dies and other reloading tools in anticipation of getting my rifle a week from Friday. I went with a Micon arbor seating die, Whidden Gunworks bushing sizing die and 21st CEntury Innovation black nitride expander mandrels with their expander die with a window.

I'm working with Eric Anderson of Blue Mountain Precision on a 25 Creedmoor barrel as well for my everyday shooting and training.

LOL, I just reviewed recent sales receipts and noticed I did order N570 too.

 

[RegionRat]

Bruce, You picked a fine rifle and I'm sure you will be happy with both powders. There is always a chance it likes one a little more than the other, and the same for the bullets.

A big magnum like this burns a lot of powder and your shot tempo determines how much heat buildup your bbl will get. That tempo becomes a dominant factor in your throat erosion. So if the rig likes the N570, don't feel like you lost anything. If you don't need to string lots of shots in short time, you will be fine. Good Luck and in for the range reports.

 

[Bruce K]

Bruce, You picked a fine rifle and I'm sure you will be happy with both powders. There is always a chance it likes one a little more than the other, and the same for the bullets.

A big magnum like this burns a lot of powder and your shot tempo determines how much heat buildup your bbl will get. That tempo becomes a dominant factor in your throat erosion. So if the rig likes the N570, don't feel like you lost anything. If you don't need to string lots of shots in short time, you will be fine. Good Luck and in for the range reports.

I'm still pondering H1000/Retumbo vs N570 as the extra 100+ fps is inticing. I plan to shoot slowly to reduce throat erosion irrespective of which powder I choose and remind myself at my age, I can't take these rifles with me and enjoy them. If I burn a barrel out, that's just the expense of shooting the 300 Norma Magnum.

However, a second barrel in 25 Creedmoor should be fun too. While Accuracy International doesn't sell a 25 Creedmoor, Eric Anderson of Blue Mountain Precision makes prefits for Accuracy International and has made me custom barrels in the past. Most of my shooting is limited to 600 yards with the 1000 yard range open on reserved days at my shooting club. Shooting past 1000 yards requires driving hours to a private home where targets are out to 2,200 yards, so I won't be doing that often.

I have several custom 6mm and 6.5mm rifles, but this is my first precison .30 caliber rifle and it just seemed like a fun rifle to own. As an older shooter I treated myself to an Accurancy International rifle, a Zero Compromise ZC840 scope and other premium accessories.

 

[RegionRat]

....I can't take these rifles with me and enjoy them. If I burn a barrel out, that's just the expense of shooting the 300 Norma Magnum.

Spot on. Enjoy the rig, you chose well.

 

[Matt_3479]

@Matt_3479 Beautiful rig and very nice shooting!

That's roughly 3600 ft*lbs worth of energy in that load!

Those are very tight groups and it is rare to see any sort of rig that can do this. Well Done!

What does your rig weigh?

Thank you,

Off the top of my head if I recall between 12.5-13.5lbs loaded.

 

[Matt_3479]

I'm still pondering H1000/Retumbo vs N570 as the extra 100+ fps is inticing. I plan to shoot slowly to reduce throat erosion irrespective of which powder I choose and remind myself at my age, I can't take these rifles with me and enjoy them. If I burn a barrel out, that's just the expense of shooting the 300 Norma Magnum.

However, a second barrel in 25 Creedmoor should be fun too. While Accuracy International doesn't sell a 25 Creedmoor, Eric Anderson of Blue Mountain Precision makes prefits for Accuracy International and has made me custom barrels in the past. Most of my shooting is limited to 600 yards with the 1000 yard range open on reserved days at my shooting club. Shooting past 1000 yards requires driving hours to a private home where targets are out to 2,200 yards, so I won't be doing that often.

I have several custom 6mm and 6.5mm rifles, but this is my first precison .30 caliber rifle and it just seemed like a fun rifle to own. As an older shooter I treated myself to an Accurancy International rifle, a Zero Compromise ZC840 scope and other premium accessories.

H1000 and retumbo should be easier on throats. You’ll love the 25 creed, I’m sure you’ll find yourself using it often. I love the 25’s. My 25 creed was great and I love my 25x47!