Can I use the RCBS Neck Expander Plug .338 as a standalone item in my reloading press?

No, this plug cannot be used on its own. It requires a dedicated RCBS Neck Expander Die body and a matching Plug Rod to function correctly in your reloading press. It is specifically precision-machined to thread onto standard RCBS expander rods.

What specific .338 calibre cartridges is this expander plug designed to handle?

The R39877 plug is engineered specifically for .338 calibre rifle cartridges, including popular rounds among Australian hunters and target shooters such as the .338 Lapua Magnum, .338 Winchester Magnum, and .338 Federal. It expands the inner case neck and flares the mouth to ensure proper bullet tension.

Why is this plug recommended when reloading cast lead bullets for my .338 rifle?

When loading cast lead bullets, this plug performs a vital two-in-one operation by expanding the inner neck diameter and slightly belling the case mouth. This slight flare prevents the sharp brass case edges from shaving off lead, wax, or copper plating as you seat the bullet, preserving both bullet weight and overall accuracy.

Are there any electrical or regulatory compliance requirements for this reloading component in Australia?

No, electrical and safety certifications such as SAA or RCM and Australian 240V plug requirements do not apply to this product. The RCBS Neck Expander Plug is an entirely mechanical, non-powered steel handloading component designed for benchtop use.

.338 Reloading Plug - RCBS R39877

The RCBS Neck Expander Plug .338 (part number R39877) is a precision-engineered reloading component designed to prepare cartridge case necks for seating .338 calibre bullets. Operating entirely mechanically without electrical power, this component threads onto a compatible expander plug rod inside an RCBS Neck Expander Die body. In a single press stroke, it performs a dual-action operation: it expands the case neck's inner diameter to the exact size required for consistent bullet tension, while simultaneously adding a slight flare to the case mouth to ensure smooth bullet entry.

Key Features

Two-in-One Operation: Expands the internal neck diameter and flares the case mouth in a single stroke, streamlining the reloading process.
Cast Bullet Protection: The slight mouth flare prevents the sharp edges of the brass case from shaving away lead, wax, or copper plating from cast rifle bullets during seating.
Concentricity and Alignment: Ensures bullets sit straight when entering the seating die, which improves overall cartridge concentricity and accuracy.
Durable Construction: Made from hardened steel for a long service life during indoor bench reloading.

Product Specifications

Brand: RCBS
Model/Part Number: R39877 (39877)
Calibre: .338 inches
Weight: 0.0188 lbs (approximately 8.5 grams)
Dimensions: 3.55" L x 2.50" W x 0.70" H (9.0 cm x 6.4 cm x 1.8 cm)
Thread Compatibility: Designed to fit standard RCBS expander plug rods used in common 7/8"-14 reloading presses.

Who is the Rcbs Neck Expander Plug .338 for?

Handloaders using cast lead rifle bullets — prevents the shaving of lead, wax, or copper plating during seating by utilizing this specialized reloading neck expander plug to expand and flare case mouths to accommodate projectiles measuring .338 inches in diameter.
Precision rifle reloaders loading magnum cartridges — improves cartridge concentricity and bullet alignment for high-power cartridges like the .338 Lapua Magnum with an ultra-lightweight reloading neck expander plug weighing just 0.0188 lbs to establish uniform neck tension.

Less suitable for: reloaders working with cartridge calibres other than the .338-inch standard, or those who do not own the required RCBS Neck Expander Die body and matching Plug Rod; these users require a different calibre-specific neck expander plug or a complete standalone expander die set matching their specific calibre dimensions.

SKU	RC39241LP
Model #	R39877
Brand	Rcbs
Shipping Weight	1.0000kg

What our Customers are Saying

We Also Recommend

Primos Hunting Game Caller Randy Anderson Predator

$61.95

Lyman Trius Trap Birdshooter 2 Fully Adjustable Wi

$160.95

Allen Cascade Neoprene Gun Sling With Molded Ends

$56.95

Cci Maxi Mag 22 Wmr 40gr Jhp Rimfire Ammunition 18

$34.95

Recommended Products

Redding 80209 Die Set 45-70 Govt 3-Die Reloading K

$201.95

Lyman Ly-Btn Brass Tapper Reloading Tool Nylon End

$26.95

Lee Precision 90843 30-40 Krag Carbide Factory Cri

$33.95

Redding 10813 Decapping Rod Assembly 308 Wincheste

$42.95

Welcome to Xhunter Australia. By accessing and using our website (www.xhunter.com.au) and purchasing from our online store, you agree to be bound by the following Terms and Conditions. Please read them carefully before proceeding.

1. Eligibility

By agreeing to these Terms and Conditions, you confirm that:

• You are at least 18 years of age.
• You are legally capable of entering into a binding contract under Australian law.
• You will not purchase any restricted or controlled items unless legally permitted to do so.

2. Product Information

• All products listed are subject to availability.
• Product descriptions, specifications, and pricing are subject to change without notice.
• We make every effort to display products accurately, although we do not guarantee that all images or content are error-free.

3. Orders and Payments

• All orders are subject to acceptance and confirmation.
• Prices are in AUD and include GST unless otherwise stated.
• We reserve the right to cancel or refuse any order at our sole discretion.
• Full payment is required before dispatch.

4. Authority to Leave (ATL) and Delivery

• By default, all orders are shipped with Authority to Leave (ATL).
• If you require Signature on Delivery, please contact us prior to purchasing. Additional charges apply.
• If an order is returned to us due to failed delivery or non-receipt when ATL is not permitted, a $25 return processing fee must be paid before reshipment or refund.

5. Returns and Refunds

• Please refer to our full Returns Policy on the website.
• Returned items must be in original, resalable condition unless faulty.
• A restocking fee may apply if an item is not in reselling condition.
• Change-of-mind returns may not be accepted for clearance or custom-ordered items.

6. Firearms and Restricted Items

• You must comply with all relevant State and Federal laws for regulated products.
• You are responsible for ensuring proper licences and permits are held.
• We reserve the right to request proof of eligibility before dispatch.

7. Limitation of Liability

• Xhunter Australia is not liable for direct or indirect losses arising from the use or misuse of products.
• We are not responsible for any unauthorised modifications or incorrect application of products.

8. Manufacturer Warranty Support

Some products sold by Xhunter Australia include a manufacturer’s warranty (for example, limited lifetime warranties). These warranties are provided solely by the manufacturer and are separate from the consumer guarantees under Australian Consumer Law.

Where a manufacturer provides a warranty:

A. The warranty is offered and honoured by the manufacturer, not by Xhunter Australia, unless expressly stated otherwise.
B. Customers may be required to contact the manufacturer directly and comply with their warranty process, which may include overseas product assessment.
C. Proof of purchase is required to lodge a manufacturer warranty claim.
D. Assistance provided by Xhunter Australia in lodging warranty claims is a goodwill service only and does not imply liability for warranty outcomes or decisions.

Nothing in this clause limits your rights under Australian Consumer Law.
Xhunter Australia remains responsible for providing legally required remedies for products that fail to meet the consumer guarantees of acceptable quality, fitness for purpose, and reasonable durability.

9. Privacy

Your personal information is collected, used, and stored in accordance with our Privacy Policy.

10. Intellectual Property

All text, graphics, logos, and images on this website remain the property of Xhunter Australia and are protected by copyright laws.

11. Amendments

We may update or modify these Terms and Conditions at any time without prior notice. Continued use of our site constitutes acceptance of any updated Terms.

12. Governing Law

These Terms and Conditions are governed by the laws of Victoria, Australia. Any disputes will be handled exclusively by the courts of Victoria.

13. 18+ Age Requirement

By placing an order, you confirm that you are at least 18 years of age and legally entitled to purchase the products ordered. We may cancel any order that breaches this requirement.

Rcbs R39877 Neck Expander Plug 338 Calibre Reloading Tool

Secure Payment Methods