Peterson .375 EnABELR Brass – 50 Cases

Peterson .375 EnABELR is American-made Match-Grade brass developed for Extreme Long Range shooting. The cartridge was created through cooperation between Peterson Cartridge, Bryan Litz and Applied Ballistics. Its purpose was to deliver performance comparable to the .375 CheyTac in a shorter, wider cartridge capable of magazine feeding.

The correct name is .375 EnABELR, although the simplified spelling “.375 Enabler” is also commonly used in searches and product listings. EnABELR stands for “Engineered by Applied Ballistics for Extreme Long Range.”

Product specifications

• Calibre: .375 EnABELR
• Manufacturer: Peterson Cartridge Company
• Manufacturer’s code: 40022-R / 40022R
• UPC for the 50-case box: 810068270150
• Quantity: 50 cases
• Condition: new and unprimed
• Quality class: Match-Grade
• Case type: bottleneck with rebated rim
• Primer pocket: Large Rifle
• Nominal flash-hole diameter: 0.080 in / 2.03 mm
• Bullet calibre: .375 in
• Material: high-quality cartridge brass
• Factory-annealed neck and shoulder
• Country of manufacture: USA
• Application: ELR, long-range competition and precision rifles

Large Rifle Magnum primers are commonly used in cartridges of this capacity, but primer selection must follow current, verified load data. The physical primer-pocket size is Large Rifle.

Dimensions from the official Peterson drawing

The original Peterson drawing specifies dimensions in inches. The metric values below are rounded conversions.

Unless a separate tolerance is shown, the drawing specifies a general diameter tolerance of −0.008 in. Peterson notes that the drawing is subject to change.

The .375 EnABELR is not currently covered by a public SAAMI or C.I.P. standard. Pressure limits for the .375 CheyTac or other similar cartridges must not be assigned to the .375 EnABELR.

Latest Peterson lot data

The latest .375 EnABELR lot currently published by Peterson is C174, inspected on 28 January 2025:

Comparison of recent production lots

These measurements are reference values for individual production lots, not guaranteed dimensions for every box. When changing lots, internal capacity, shoulder position, neck thickness and die settings should be checked again.

Original Applied Ballistics design

The .375 EnABELR is not simply a modified version of an existing cartridge. According to Peterson, it has no parent case and was designed from the ground up. Peterson contributed to its internal construction, including case-wall and web thickness.

Compared with the .375 CheyTac, the EnABELR case is:

• shorter;
• wider;
• equipped with a rim smaller than the case body;
• designed for a shorter cartridge overall length;
• intended to allow magazine feeding with long ELR bullets;
• similar in internal capacity.

Recent Peterson .375 EnABELR lots have approximately 155–156 gr H₂O capacity, compared with approximately 159–160 gr H₂O for Peterson .375 CheyTac brass. The wider body therefore retains substantial capacity while allowing a noticeably shorter case.

Magazine feeding depends on the rifle, chamber, cartridge overall length and magazine design. It does not mean that the cartridge will feed from every magazine designed for the .375 CheyTac.

Main design advantages

The .375 EnABELR was developed to reduce problems associated with extremely overbore ELR cartridges, including heavy fouling, increasing velocity and pressure during extended shot strings and a very short period of stable barrel performance.

Applied Ballistics identifies the following advantages:

• ELR performance from a more balanced case capacity;
• compatibility with long, very-high-BC bullets;
• magazine-feeding capability in properly designed systems;
• reduced tendency for velocity migration during extended shooting;
• more predictable ballistic performance;
• lower cleaning requirements than larger extreme wildcats;
• no need to form cases from another calibre;
• availability of finished brass, dies and chamber reamers;
• good case life when operated within suitable pressure limits.

The cartridge was developed primarily around heavy, high-BC .375-calibre bullets, including the Berger 379 and 407 gr Solids and comparable ELR projectile designs.

Applied Ballistics testing

Before the cartridge was commercially released, Applied Ballistics conducted testing for most of a year using four competition rifles and four test rifles. Different barrel lengths, twist rates and projectiles were evaluated.

Early prototype Peterson cases were used at least eight times during load development. Applied Ballistics reported good durability, provided the cases had not been subjected to excessive pressure that permanently expanded the case head.

The testing team did not report unexplained velocity migration or unusual cartridge-related problems during its competition season. The .375 EnABELR was also used successfully in ELR competitions at distances exceeding two miles.

Testing and competition results demonstrate the potential of the design but do not guarantee a particular level of accuracy, velocity or number of reloads.

Benefits reported by shooters

Users of Peterson .375 EnABELR brass most frequently mention:

• a very strong case head;
• tight and consistent primer pockets;
• repeatable internal capacity;
• good durability through repeated reloadings;
• uniform neck dimensions;
• consistent factory annealing;
• no need to form brass from another cartridge;
• performance comparable to the .375 CheyTac in a shorter cartridge;
• suitability for magazine-fed ELR rifles;
• manufacturing quality appropriate for precision ammunition.

User reports describe cases remaining in good condition after five, eight or more firings. Actual case life depends on pressure, chamber dimensions, die adjustment, shoulder bump and annealing frequency.

Some users describe the primer pockets as exceptionally tight. A suitable priming tool should be used, and the pockets should not be modified without first taking accurate measurements.

Reloading-equipment compatibility

Specialist .375 EnABELR dies are available from manufacturers including Forster and Whidden. Because of the case size, some die sets use 1¼-12 press threads rather than the standard 7/8-14 thread.

Applied Ballistics specifies compatibility with a No. 47 shell holder. Shell-holder numbering may differ between equipment manufacturers.

Before purchasing or adjusting dies, check:

• compatibility with the current chamber drawing;
• case-body diameter after sizing;
• shoulder position after sizing;
• required neck-bushing diameter;
• the thread size of the reloading press;
• loaded-cartridge fit in the magazine.

Older user reports mention that some die versions did not sufficiently size the case body. This did not necessarily indicate defective brass, but could result from a mismatch between the die, chamber and dimensions of the specific brass lot.

Preparation before first use

1. Inspect every case for shipping damage.
2. Measure case length, base diameter and shoulder position.
3. Verify headspace and proper chamber fit.
4. Check neck clearance with the intended loaded-cartridge dimensions.
5. Lightly chamfer or deburr the case mouth if required.
6. Adjust the sizing die using chamber measurements and brass fired in the specific rifle.
7. Use only verified load data developed specifically for the .375 EnABELR.

Because the cartridge is not standardized by SAAMI or C.I.P., .375 CheyTac data must not be used merely because the two cartridges have similar capacities and use bullets of the same calibre.