If you’ve got a 25 Creedmoor and want to load top quality ammunition, Peterson Brass is a great starting point. Follow along as I do some load development for my new 25 Creedmoor build!
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About the Build
With the SAAMI- certification of the 25 Creedmoor cartridge, I decided it was time for another 25 Creedmoor. This time I turned to a 1934 Armory BE1 action and chambered a Custom Rifle Barrels (CRB) super heavy contour 1:7.5 .257 barrel blank on my PM-1440HVT-2.
I decided to use the same trigger I did in my 7mm SWC build, the Bix’n Andy TacSport Pro-X Trigger from Bullet Central, along with tried-and-true Foundation Genesis 2 micarta stock and Hawkins Precision M5 DBM. I topped the rifle with a Telson Target Master 5-25×56 in XLR 34mm rings and an Area 419 HELLFIRE brake.
About Peterson Cartridge 25 Creedmoor SRP Brass
SAAMI-certification established official cartridge and chamber specifications, opening the door for manufacturers like Peterson to make 25 Creedmoor brass!
The 25 Creedmoor takes an 87 to 134 grain 0.257” bullet and splits the tradeoffs in recoil, barrel life, and long range ballistics between the 6mm and 6.5 Creedmoor. It performs better in wind and has longer barrel life than a 6mm Creedmoor, but less recoil than a 6.5 Creedmoor.
I decided to load small rifle primer brass, but Peterson also offers .25 Creedmoor large rifle primer cases. (I prefer large rifle primers for hunting in cold temperatures, but small rifle primers for all other scenarios.)
From Peterson Brass:
Match-Grade is a standard that must be held throughout the entire process of manufacturing some of the most consistent, accurate, and durable brass rifle casings available today. From our small batch production lines to our quality control department, to your bench, and on to the range. Match-grade is the standard that we strive to achieve so that our customers can maintain that standard all the way to the target.
*Note: All our SRP casings feature a small flash hole in the diameter of 0.060” vs. the 0.080” flash hole found in our LRP casings. This means you will need an X-small/ Undersized Decapping Pin to deprime our casings.
Loading
The 25 Creedmoor retains the .308 case rim, but with a smaller and slightly longer neck than 6.5 Creedmoor. It is optimized for long, high BC bullets. I fired a number of rounds at my 100-yard range, seeking to evaluate the rifle, brass, and three different bullets.
I started with a load I had previously worked up: 131 grain Blackjack bullets over 42.6 grains H4350 in Peterson Small Rifle Primer Brass. This load performed well, my first three-shot group at 100 yards measuring 0.237”. Five rounds went into 0.662”, traveling 2,933.5 fps with a 10.1 fps standard deviation.
For the rest of my load development, I decided to transition to Vihtavuori N555, a powder with a burn rate very similar to H4350 and ideal for creedmoor cartridges.
I had started with the Blackjack bullets simply because that is what I had used previously, but decided to test two high BC bullets, Hornady’s .25 Caliber 138 Grain A-Tip and the Berger .25 Caliber 135 Grain Long Range Hybrid Target Bullet.
I started with three shot groups and if I really liked how that charge weight performed, I fired a five-shot group. I loaded four different charge weights with the Hornady A-Tips, achieving an average group size of 0.462”.
Velocities ranged from 2765.2 fps to 2867.8 fps, all with tight standard deviations (SD).
I tested three different charge weights with the Berger 135 — all velocities exceeded 2900 fps.
My most impressive three-shot group measured 0.113” with an average velocity of 2,934 fps.
I fired a five-shot group with this load and the SD grew from 7.1 fps to 12.5 fps and the group size rose to 0.619” with a flyer.
At this point, I decided to up the power charge and fire another five-shot group. The result was a 0.355” five-shot group with a 2,945.9 fps velocity and 16.4 fps SD.
Lab Results
Kyle Shields performed some length, weight, and case neck measurements to evaluate the consistency of the Peterson Brass.
The average length was 1.9083” with an SD of 0.0003” and extreme spread (ES) of 0.0010”. This was very impressive!
The cases had an average weight of 164.6850 grains, an SD of 0.3104 grains, and an ES of 1.0400 grains.
While not as consistent as the length, this was a very small measurement in the grand scheme of things. The measured cases had an average case neck thickness of 0.01414” with an SD of 0.00056” and ES of 0.00210”.
Conclusion
If I decide to continue load development looking at group size, I will continue with the Berger 135 grain Long Range Hybrid Target Bullets and adjust seating depth.
The overall average group size across all loads and all three bullets tested was 0.444”, under 0.5 MOA, which is splendid performance. I was very pleased with the consistency of Peterson’s 25 Creedmoor brass and am thrilled to have this off-the-shelf option rather than wildcatting!
Get the Gear
Peterson Cartridge 25 Creedmoor Small Rifle Primer Brass
Peterson Cartridge 25 Creedmoor Large Rifle Primer Brass
Hodgdon H4350 at Midsouth Shooters Supply
Hornady .25 Caliber 138 Grain A-Tip Bullets at Midsouth Shooters Supply
Berger .25 Caliber 135 Grain Long Range Hybrid Target Bullets at Creedmoor Sports and Midsouth Shooters Supply
Vihtavuori N555 at Midsouth Shooters Supply
A&D FX-120i Precision Balance (CE Products)
Custom Rifle Barrels 25 Creedmoor 1:7.5 Barrel Blank
Telson Target Master 5-25×56 Scope
Bix’n Andy TacSport Pro-X Trigger from Bullet Central
Precision Matthews PM-1440HVT-2 Lathe
Area 419 Loading Block at Midsouth Shooters Supply
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Thanks,
Gavin Gear
Hi
new to this and extremely interessted in the .25 CM
but i have questions on the bullet sizes… why does the site show .257 (6.52mm) which is the same as the 6.5 CM. when a .25 CM should then use a bullet of .25 (6.35mm)
not sure what the differences are then and just as well go for a 6.5 when they then use the same size bullet.
sorry i am new to this and greatly confused with the data and my thinking of size 6.5 vs .25 CM
The 25 Creedmoor uses .257″ bullets.
The 6.5 Creedmoor uses .264″ bullets.
Hope that clears up any confusion. Regards, Guy