Peterson .260 Rem SRP Brass cases

Peterson .260 Remington SRP is premium rifle brass developed for shooters who demand maximum consistency when producing precision ammunition. The SRP version uses a Small Rifle Primer pocket and a smaller 0.060" flash hole, equivalent to approximately 1.52 mm.

The cases are manufactured in the USA from C260 cartridge brass. Every case passes through a multi-stage, closely monitored production process. The neck and shoulder are induction annealed to improve brass ductility and potentially extend case life through repeated firing and resizing cycles.

Visible discolouration around the neck and shoulder is a natural result of the annealing process. It is not a product defect. Peterson leaves the annealing marks visible instead of removing them through additional polishing.

The .260 Remington combines a case from the .308 Winchester family with aerodynamic 6.5 mm bullets. It allows high-ballistic-coefficient projectiles to be used in rifles with short-action receivers. Peterson SRP brass is particularly well suited to F-Class, PRS, long-range target shooting, benchrest and other disciplines where ammunition consistency is essential.

Key advantages

• Match-Grade quality for precision ammunition
• Small Rifle Primer pockets
• Small 0.060" / approximately 1.52 mm flash hole
• Excellent dimensional consistency
• Uniform neck-wall thickness
• Consistent internal capacity
• Strong case-head construction
• Primer pockets designed to remain tight over repeated firing cycles
• Potentially longer service life than some LRP cases
• Potential for low velocity SD and ES after proper load development
• Induction-annealed neck and shoulder
• High-quality C260 cartridge brass
• Manufactured and quality-controlled in the USA
• Convenient box containing 50 cases

Technical specifications

• Manufacturer: Peterson Cartridge
• Calibre: .260 Remington
• Product type: new, unprimed rifle brass cases
• Primer pocket: Small Rifle Primer – SRP
• Flash-hole diameter: 0.060" / approximately 1.52 mm
• Case type: rimless, bottleneck
• Material: C260 cartridge brass
• Neck and shoulder: induction annealed
• Quantity: 50 cases
• Manufacturer’s product code: 40009-R / 40009R
• Commercial designation: PC260RMSP
• UPC: 859449006582
• Country of manufacture: USA
• Quality class: Match-Grade

SAAMI cartridge and case dimensions

• Maximum case length: 2.035" / 51.69 mm
• Cartridge overall length: 2.530–2.800" / 64.26–71.12 mm
• Maximum case-head diameter: 0.473" / 12.01 mm
• Case-body diameter near the base: 0.4703" / 11.946 mm
• Shoulder diameter: 0.4553" / 11.565 mm
• Maximum outside neck diameter: 0.297" / 7.54 mm
• Bullet diameter: 0.2645" / 6.718 mm
• Shoulder angle: 20°

Peterson reference data – SRP lot N088

The following measurements were published by Peterson for production lot N088, inspected on 28 February 2024:

• Average empty case weight: 176.4 grains / approximately 11.43 g
• Average internal capacity: 53.2 grains of water / approximately 3.45 cm³
• Shoulder diameter: 0.452" / approximately 11.48 mm
• Base diameter: 0.469" / approximately 11.91 mm
• Neck-wall thickness: 0.0153" / approximately 0.389 mm
• Loaded neck diameter: 0.295" / approximately 7.49 mm
• AMP Aztec annealing code: 0156
• AMP pilot: No. 11
• Testing equipment: AMP Mark II

These values apply to the tested production lot and should be treated as reference data. Actual measurements may vary slightly between production lots.

Why choose the SRP version?

A smaller primer pocket leaves more material in the case-head area. This can improve case-head strength and help the primer pocket remain tight through more firing and reloading cycles.

Competitive shooters also report the potential for more consistent ignition and lower velocity standard deviation and extreme spread. Results depend on the primer, powder, rifle and complete load configuration. Using SRP brass alone does not guarantee improved accuracy.

User reports also mention significantly longer primer-pocket life with SRP cases. These are individual shooter experiences and should not be treated as a guaranteed number of reloads.

Important SRP information

These cases have a 1.52 mm flash hole. An appropriately sized undersized or X-Small decapping pin is required. A standard decapping pin intended for larger LRP flash holes may be too thick and could become stuck or damaged.

Some rifles may require a bolt with a correctly fitted, smaller-diameter firing pin. Excessive clearance between the firing pin and its channel can contribute to primer cratering or pierced Small Rifle primers.

In very low temperatures, a Small Rifle primer may provide less energetic ignition than a properly selected Large Rifle primer. For hunting ammunition intended for use in freezing conditions, the LRP version may be the more predictable choice.

Preparing new cases

According to Peterson, new cases do not require extensive preparation. The manufacturer recommends only lightly chamfering and deburring the case mouth. Full-length sizing new Peterson brass is generally unnecessary because all cases within a production lot are manufactured using the same tooling.

Every case should nevertheless be inspected and measured before use, taking into account the rifle chamber, sizing dies and selected bullet.

Important reloading information

Peterson cases may differ in weight, wall thickness and internal capacity from brass produced by other manufacturers. Changing the case brand or switching between LRP and SRP brass can affect pressure and muzzle velocity.

Do not transfer an established load directly between LRP and SRP cases. After changing the case type, begin load development again using safe starting data from a current reloading manual or powder manufacturer.

The package contains empty, unprimed cartridge cases only. Primers, powder, bullets and loaded ammunition are not included.

Frequently asked questions

Are primers included?

No. These are new, unprimed cartridge cases. Small Rifle primers must be purchased separately.

What does SRP mean?

SRP stands for Small Rifle Primer. These cases have primer pockets designed for Small Rifle primers.

What is the flash-hole diameter?

The flash hole measures 0.060", equivalent to approximately 1.52 mm.

Is a special decapping pin required?

Yes. Due to the smaller flash hole, an X-Small or undersized decapping pin is recommended. A standard pin may be too thick.

Does SRP brass produce better accuracy than LRP brass?

Not necessarily. Some shooters report lower SD and ES values, while others see no significant difference in group size. The primary benefit may be the stronger case-head structure and longer primer-pocket life.

Is the SRP version suitable for cold-weather shooting?

It can function correctly, but ignition depends on primer type, powder and temperature. For ammunition intended for very low temperatures, Peterson identifies LRP brass as the option providing more dependable primer ignition.

Are the marks around the case neck a defect?

No. They are natural signs of factory annealing applied to the neck and shoulder.

Can an LRP load be used directly in SRP cases?

It should not be transferred without new load development. Differences in ignition, case-head construction and internal capacity can affect pressure and velocity.