Federal Gold Medal Match Small Rifle Primers No. GM205MAR

Overview:

The GM205MAR is a Gold Medal® Match-grade small rifle primer designed specifically for use in AR-style platforms, especially those chambered in calibers like .223 Remington/5.56 NATO. It offers precise ignition, reliable performance, and consistent shot-to-shot accuracy, making it ideal for competitive shooters, reloaders, and precision marksmen.

Key Features:

Feature	Details
Primer Type	Small Rifle Match Primer
Product Code	GM205MAR
Brand	Federal Premium
Series	Gold Medal® Match
Use Case	Reloading for AR-15 platforms and similar semi-autos
Sensitivity	Less sensitive than standard primers to reduce risk of slam-fires
Consistency	Designed for uniform ignition and reduced velocity spreads
Priming Mix	Non-corrosive and temperature-stable
Cups	Match-quality cups engineered for semi-auto bolt strike characteristics
Packaging	Commonly available in boxes of 100 or bricks of 1000

Design Intent:

The GM205MAR is purpose-built for semi-automatic rifles, with specific attention paid to:

Preventing slam-fires, which can occur with soft primers in free-floating firing pin systems like the AR-15.
Withstanding higher bolt carrier impacts typical in AR platforms.
Offering tight tolerances and precision similar to benchrest-quality primers.

Comparison to Other Primers:

Primer Type	Cup Hardness	Application Type	Sensitivity	Use in AR-15
CCI 400	Softer	General small rifle	Higher	Risk of slam-fire
CCI #41	Harder	Military spec 5.56 NATO	Moderate	Yes
GM205MAR	Harder	Precision AR-15 loads	Moderate	Yes ✅
BR-4 (Federal)	Match-grade	Bolt-action precision	Low/moderate	Caution

Note: GM205MAR is similar in construction to the CCI #41 primer in hardness but built with match consistency in mind.

Applications:

Precision reloading for .223 Remington, 5.56 NATO, and similar small rifle cartridges.
AR-15 and other semi-auto platforms.
Match shooting, including Service Rifle competitions and PRS Gas Gun divisions.
Ideal for reloaders seeking low standard deviations (SDs) and extreme spread (ES) in their ammo.

Important Reloading Considerations:

Seating Depth: Always seat primers below flush. Improper seating can affect ignition and pressure.
Powder Compatibility: Works well with popular powders like Varget, H4895, TAC, CFE223, etc.
Testing Needed: Due to tight tolerances, always test batches to ensure your rifle’s firing pin consistently ignites these harder primers.
Storage: Store in a cool, dry environment, away from static electricity or open flame.

Availability and Cost:

Often in high demand due to their performance and military-style application.
Price can range from $80–$130 per 1000, depending on market conditions.
May be subject to purchase limits or backorders due to supply chain constraints.

User Reviews & Community Feedback:

Widely respected by competitive shooters for ignition reliability and tight group performance.
Frequently chosen by handloaders looking to optimize semi-auto rifle reloads without risking over-sensitivity.
Some reloaders report lower standard deviations than standard small rifle primers in chronograph testing.