Powder test with short barrel 30 Nosler

[thaught]

I recently built a new 30 Nosler, opting for a 22-inch barrel instead of the longer 26-28 inch barrels used in my previous builds. This rifle is equipped with a TBAC Magnus suppressor. While researching potential loads and powders, I initially assumed that a faster-burning powder would be more suitable given the shorter barrel length, as it would facilitate a complete powder burn and yield better velocity and standard deviation (SD) values. My bullet of choice was the Berger 215-grain, and I began my testing with H1000 powder. This initial load demonstrated decent accuracy and SD, with a velocity of 2,890 fps at 82 grains.

Next, I tested Retumbo, which provided significantly higher velocity, reaching 3,104 fps at the first signs of pressure, along with slightly improved SD values compared to H1000. I then tried 4831sc, which produced a velocity similar to H1000 but resulted in worse SD values. Finally, I opted for N570, the same powder I use in my other 30 Nosler rifles, and found an optimal load at 86.2 grains, achieving a velocity of 3,007 fps with an SD of 1.2 (2.8 fps extreme spread).

Contrary to my initial expectations, the shorter barrel performed better with slower-burning powders. Based on this experience, I conclude that for heavy bullets in any given caliber, slower powders yield better performance regardless of barrel length. Anyone else have similar or differing experiences?

 

[Tiny Tim]

Generally, the powder that produces the fastest velocity in a longer barrel will also do so in a shorter one. The advantage of a faster powder "MAY" be a more complete burn and as a result of this, less muzzle flash.

 

[7.62 Gunner]

Contrary to my initial expectations, the shorter barrel performed better with slower-burning powders. Based on this experience, I conclude that for heavy bullets in any given caliber, slower powders yield better performance regardless of barrel length. Anyone else have similar or differing experiences?

I wouldn't really consider 22" a short barrel, but generally you do get fastest velocity with the same powders as a standard 26" barrel according to my testing.

I will add that the bigger magnums with barrels under 20" are a bitch to tune.
I got so tired of chasing wild SDs with a 19" 300 NMI that I went back to 25", now it's an effortless ES in the single digits.

 

[Austin_Michael]

I have a 16" 300 SAUM for hog hunting from a blind, suppressed. I went to the faster burning powders to get a more complete burn which should reduce pressure at the muzzle.

My thought was it would reduce the burden on the suppressor. Only a theory, and some estimates from Quickload.

 

[Jakeweb09]

When you say 2.8 ES and 1.2 SD, how many rounds we talking in those numbers?

 

[thaught]

When you say 2.8 ES and 1.2 SD, how many rounds we talking in those numbers?

20 rounds

 

[LDHunter]

My take on this is that the 30 Nosler is a true magnum cartridge and anything short of a 24" barrel is just a waste.

Something like a 300SAUM would easily work well in a 22" barrel and, in fact, I have one. It's the "standard barrel length" for many of the Remington Model Sevens in 300SAUM.

You'll get so much muzzle flash and such a seriously loud muzzle blast that your hearing protection will not be enough to prevent hearing loss.

Having said all that the suppressor will likely negate a lot of that flash and noise but still I think it's a waste to use less than at least a 24" barrel and a 26" barrel would be more ideal.