Mighty Armory BIG BOY .375 CheyTac, XC, 50 BMG, .338 Lapua Decapping Die
Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes with .078 Decapping Pin
Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes with .058 Decapping Pin
Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes such as the 50 BMG with .110 Decapping Pin
Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes with optional thread reducer bushing
Mighty Armory 50 BMG Decapping Die Bushing
Mighty Armory Big Boy Decapping Die Locknut
Mighty Armory decapping shaft for the big boy decapping die
mighty armory steel decapping pins
Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes with .078 Decapping Pin
Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes with .058 Decapping Pin
Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes such as the 50 BMG with .110 Decapping Pin
Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes with optional thread reducer bushing
Mighty Armory 50 BMG Decapping Die Bushing
Mighty Armory Big Boy Decapping Die Locknut
Mighty Armory decapping shaft for the big boy decapping die
mighty armory steel decapping pins

Mighty Armory BIG BOY .375 CheyTac, XC, 50 BMG, .338 Lapua Decapping Die

Mighty Armory BIG BOY .375 CheyTac, XC, 50 BMG, .338 Lapua Decapping Die

Mighty Armory

$69.95
$99.95 $69.95
Sale Sold out
Shipping calculated at checkout.
The Mighty Armory BIG BOY Magnum Decapping Die is built specifically for reloaders working with .50 BMG, .375 CheyTac, .338 Lapua, XC cartridges, and other large magnum cases. From the first pull o...Read more
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Product Description

The Mighty Armory BIG BOY Magnum Decapping Die is built specifically for reloaders working with .50 BMG, .375 CheyTac, .338 Lapua, XC cartridges, and other large magnum cases.

From the first pull of the press handle, you’ll feel the difference. The BIG BOY is all strength, perfect alignment, and repeatable performance decap after decap without fail.

The BIG BOY reloading die is precision CNC machined with 1.25 x 12 threads. The decapping shaft and pin are machined from high-grade tool steel, then heat treated and tempered for ultimate durability. 

1,000 lb Bend-Rate Steel Pins – No More Snapped Pins
Mighty Armory’s flat-tip steel decapping pins are rated to withstand up to 1,000 lbs of force, dramatically reducing bent pins and primer ringers. These pins have been proven in the field since 2017.

Perfect Vertical Alignment = Less Stress on Pins
Precision CNC machining and rigid die geometry keep the pin perfectly centered through the flash hole — less flex, fewer failures, smoother operation.

The Big Boy decapping die is pictured with an optional 1.25 to 1.50 Press Bushing Reducer if needed for your press. Bushing is not included with the decapping die.

Mighty Armory Decapping Pins are toughest in the industry. Swiss machined, rolled threads, hardened tool steel, heat treated and tempered for ultimate strength.

Construction & Engineering

  • Precision CNC machined die body
  • 1.25 x 12 threads for large-format presses
  • Decapping shaft & pins made from hardened tool steel
  • Heat treated & tempered for extreme durability
  • Flat-tip pin design reduces primer ringers
  • Modular, tool-free design
  • Swiss-machined pins with rolled threads
  • Designed for perfect vertical alignment
  • Made in the USA

Compatible Cartridges

  • .50 BMG
  • .375 CheyTac
  • .338 Lapua
  • XC cases
  • Other large magnum and heavy brass cases

World’s Toughest Reloading Dies
Precision Reloading Tools
Made in the USA

Get Tough. Stay Mighty.

What's Included

  • Mighty Armory BIG BOY Decapping Die (reducer bushing is not included)
  • Two (2) Mighty Armory Steel Decapping Pins. Choose pin size: .058 for small flash hole, .078 for standard flash hole, or .110 for 50 BMG cases. 
  • Nylon Nut
  • Locknut

Popular Questions

1. How do I know which Mighty Armory Decapping Die I should choose for my reloading bench?

When selecting your decapping die, ensure the universal decapping die bore length and diameter are tall and wide enough for the case you will be decapping.

For instance, the Mighty Armory Magnum or PUA die will decap up to a .338 Lapua caliber case size. Popular caliber sizes we decap with the Magnum & PUA Decapping Dies include .308 Win, .30-06, 9mm Luger, .40 cal, .45 ACP, .44 magnum, .380 ACP, and more. 

If you are loading on a single stage or turret press, the Magnum Decapping Die or PUA Decapping Die would be your best choice. It offers a primer flicker spring to prevent primer pull back and jams down your shoot.

If you are loading on an autoindexing press, the XMS, XMA or Super Duty Dies are an excellent choice. These dies offer a primer flicker spring and a gravity case guide with an optional compression spring for the guide. 

If loading on an autodriven, autoprogressive, we recommend the XMS Decapping Die. If you're looking for a smart decapping die, select the Super Duty Decapping Die paired with our auto-drive shut-down sensors. The Super Duty Decapping Die is a 100% spring operated design.  

If loading .338 Lapua up to BMG 50, the Big Boy Decapping Die has you covered. Three pin sizes are available (.058, .078 and .110). Know the size of your flash hole before you make your decapping pin selection.

Click here for more Frequently Asked Questions

Instructions

Click Link for the Big Boy Decapping Die Instructions

Step 1. Remove the shaft from the die body. Turn the pin into the shaft.

Step 2. Add a touch of purple VIBRA-tite 111 to the shoulder of the shaft and pin. Snug it with a 3/16th wrench. Do not over-tighten the pin or could result in snapping the shaft.

Step 3. Screw the nylon nut all the way onto the shaft. Turn the shaft all the way down into the die. Hand tighten.

Step 4. Set the die into the tool head deep enough to decap your cases.

Step 5. Add the optional reducer bushing for 1.25" to 1.5" tool heads.

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Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes with .078 Decapping Pin Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes with .058 Decapping Pin Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes such as the 50 BMG with .110 Decapping Pin Mighty Armory Big Boy Decapping Die for Extra Magnum Case Sizes with optional thread reducer bushing Mighty Armory 50 BMG Decapping Die Bushing Mighty Armory Big Boy Decapping Die Locknut Mighty Armory decapping shaft for the big boy decapping die mighty armory steel decapping pins

Mighty Armory BIG BOY .375 CheyTac, XC, 50 BMG, .338 Lapua Decapping Die

$69.95
$99.95 $69.95
Sale Sold out

Go Big or Go Home!

From you moment you see the Big Boy Decapping Die, you will see the quality and strength. Understand the precision machining as soon as you turn it into your tool head and lock it down. First pull of the lever and that primer is history! Decap over and over again without fail.

MIghty Armory Decapping Die for 50 BMG cases

Powerful Refinement

7075 billet with anodized finished die body. Will not rust, will not fade, will not wear away.
decapping die for extra large case sizes

Precision Machined

CNC machined for perfect vertical alignment. Rifle barrel steel shaft will last a lifetime. M2 heat-treated steel pins will knock out primers like a boss.
Decapping dies for reloading 50 BMG and 338 lapua cases

Decaps Magnum Case Sizes

Depriming BMG 50, Cheytac, XC and 338 Cases? The Big Boy has you covered.

MIGHTY ARMORY

PRECISION MACHINED

All reloading dies are precision CNC machined for tight tolerances and perfect vertical alignment. You will immediately see, feel and shoot the difference with Mighty Armory Reloading Dies.

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SUPERIOR MATERIALS

We machine our reloading dies from high-grade, hardened tool steel built to withstand the pressures from automated and lever presses. Our dies are designed and built with quality materials to last a lifetime on your press.

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MADE IN AMERICA

Our goal at Mighty Armory is absolute quality products and customer service. We take pride in our innovative designs and precision machining. We don't believe in cutting corners and don't mass produce. American craftmanship is at the heart of our business.

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