300 AAC Blackout, 200 Gr Maker REX (Rapid EXpanding), Subsonic – 20 Rounds

300 AAC Blackout 200gr Maker REX Subsonic - Premium SBR Hunting Ammunition

The Just Cause Solutions 300 AAC Blackout 200gr Maker REX Subsonic is purpose-built for short-barrel rifle (SBR) hunting applications. Extensively used by hunters for taking whitetail deer, feral hogs, and black bear from suppressed platforms, this load delivers devastating terminal performance while remaining whisper-quiet. The precision CNC-machined Maker REX projectile expands to nearly three times its original diameter while maintaining 100% weight retention, making it one of the most effective subsonic hunting cartridges available.

Just Cause Solutions pressure tests every lot of ammunition using a PCB Piezotronics Conformal Transducer according to Voluntary Industry Performance Standard as set forth by SAAMI. Your safety and consistent performance are our priorities.

The Ultimate SBR Hunting Load

The 300 Blackout was designed specifically for short-barrel suppressed platforms, and this 200gr Maker REX load represents the perfect marriage of cartridge and bullet design. Key advantages include:

• Optimized for 7"-10.5" barrels - Delivers full subsonic performance from SBR platforms
• Devastatingly quiet - Subsonic velocities eliminate the sonic crack for true stealth
• Proven on medium game - Successfully used on whitetail deer, feral hogs, and black bear
• Massive wound channels - Expands to nearly 3x diameter (.308" to ~.900")
• 100% weight retention - Deep, straight-line penetration through bone and tissue
• Magazine compatible - Feeds reliably from standard AR-15 magazines

Maker REX Technology - Maximum Subsonic Performance

The Maker REX bullet is precision CNC-machined from solid copper with engineered expansion channels specifically designed for subsonic velocities. Upon impact, the REX projectile expands to nearly three times its original diameter (.308" to approximately .900") while maintaining 100% weight retention.

This combination delivers:

• Maximum energy transfer at subsonic speeds
• Massive wound channels for quick, humane kills
• Deep penetration even through heavy shoulder bones
• Reliable expansion across the entire subsonic velocity range
• Straight-line penetration without tumbling or yaw

Proven Performance on Game

This load has been extensively used by hunters to harvest:

• Whitetail deer - Clean, one-shot kills from suppressed SBRs
• Feral hogs - Effective stopping power on tough, dangerous game
• Black bear - Deep penetration through heavy bone structure

The 200gr Maker REX delivers the terminal performance needed for ethical hunting while maintaining the stealth advantages that make 300 Blackout subsonic so effective.

Best Applications

Perfect For:

• Suppressed hunting - Maximum stealth for close-range opportunities
• Short-barrel rifles (7"-10.5") - Optimized for SBR platforms
• Whitetail deer hunting - Proven effective within appropriate ranges
• Feral hog control - Quick kills on dangerous game
• Black bear hunting - Deep penetration on heavy-boned animals
• Close to medium range hunting (50-150 yards) - Subsonic trajectory considerations
• Situations requiring minimal noise signature - Truly quiet hunting

Optimal Range: Maximum effectiveness 50-150 yards. The subsonic trajectory requires understanding holdovers beyond 100 yards.

It is the hunter's responsibility to adequately test their rifle system at distance prior to hunting wild game!

Technical Specifications

Barrel Length & Velocity Data

All velocities remain subsonic (under 1100 fps). The 300 Blackout was engineered for optimal subsonic performance from short barrels. Always verify your specific rifle's performance and practice at your intended hunting distances.

Platform Compatibility

Optimized For:

• AR-15 pistols and SBRs (7"-10.5" barrels)
• AR-15 carbines (16" barrels)
• Bolt-action 300 Blackout rifles
• Any firearm chambered in 300 AAC Blackout

Requirements:

• 1:8 twist or faster recommended - Most 300 Blackout barrels use 1:7 or 1:8 twist
• .30 caliber suppressor minimum (not .223/5.56 size)
• Adjustable gas block recommended for reliable cycling in semi-autos
• Standard AR-15 magazines work perfectly

Why 300 Blackout Subsonic for Hunting?

Advantages Over Other Subsonic Options:

• Purpose-built for SBRs - Designed from the ground up for short suppressed barrels
• AR-15 platform - Lighter, more compact than AR-10 based cartridges
• Standard magazines - Uses regular AR-15 magazines without modification
• Proven cartridge - Decades of development and real-world use
• True subsonic - No sonic crack even from 16" barrels
• Devastating expansion - Maker REX provides rifle-caliber wound channels

Ideal Hunting Scenarios:

• Stand hunting where stealth is paramount
• Properties where noise complaints are a concern
• Close-range thick cover hunting
• Follow-up shots on moving hogs without spooking the herd
• Areas where supersonic crack would alert game

Understanding Subsonic Trajectory

Subsonic ammunition has significantly more drop than supersonic loads. Understanding this is critical for ethical hunting:

• 50 yards: Minimal holdover needed, aim point-of-impact
• 100 yards: Approximately 6-10" of drop depending on zero
• 150 yards: Significant holdover required, practice essential

Practice at your intended hunting distances. Know your holdovers. Understand your effective range before hunting.

Comparison: 300 BLK vs Other Subsonic Options

Important Safety Notes

• Twist Rate: This 200gr bullet requires 1:8 twist or faster. Most 300 Blackout barrels use 1:7 or 1:8 twist and will stabilize this bullet correctly.
• Suppressor Requirement: Ensure your suppressor is rated for .30 caliber minimum. Do not use .223/5.56 suppressors on 300 Blackout.
• NOT for 5.56 NATO or .223 Remington: 300 Blackout will chamber in 5.56/.223 rifles, which will cause catastrophic failure. Always verify your chambering before loading.
• Range Limitations: Subsonic ammunition has limited effective range. Practice at your intended distances and understand trajectory drop.
• State Hunting Regulations: Verify that subsonic ammunition and short-barrel rifles are legal for your intended game in your jurisdiction.
• Semi-Auto Tuning: Subsonic loads may require adjustable gas blocks for reliable cycling in semi-automatic platforms.

Why Just Cause Solutions?

Every lot of our 300 Blackout ammunition is:

• Pressure tested using a PCB Piezotronics Conformal Transducer according to SAAMI standards
• Loaded with premium Maker REX projectiles proven on game
• Optimized for short-barrel suppressed platforms
• Manufactured with consistent subsonic velocities
• Made by an Operation Iraqi Freedom veteran-owned company
• 100% made in the USA with American components

If we don't test it, we don't release it.

Frequently Asked Questions

Q: Will this work from my 7.5" AR-15 pistol?
A: Yes. This load is optimized for short barrels and delivers full performance from 7" SBRs and pistols.

Q: Is this powerful enough for deer hunting?
A: Yes, within appropriate ranges (50-150 yards). The 200gr Maker REX has been proven on whitetail deer, providing clean kills with proper shot placement. The massive expansion and deep penetration deliver adequate terminal performance for deer-sized game.

Q: How quiet is this with a suppressor?
A: Extremely quiet. Being true subsonic (no sonic crack), the only sound is the action cycling and the bullet impact. It's hearing-safe without additional ear protection when suppressed.

Q: Can I use this for home defense?
A: Yes. The controlled expansion and deep penetration make it effective for defense while being quieter than supersonic loads if using a suppressor.

Q: What's the effective range for hunting?
A: We recommend 50-150 yards as the practical hunting range. Beyond 150 yards, the subsonic trajectory makes precise shot placement challenging. Always practice at your intended distances.

Q: How does this compare to your 8.6 Blackout subsonic loads?
A: The 8.6 Blackout delivers more energy and penetration (350gr at similar velocities = ~750 ft-lbs vs 400-430 ft-lbs). However, 300 Blackout runs on the lighter, more compact AR-15 platform with standard magazines. Choose 300 BLK for lighter rifles, 8.6 BLK for maximum subsonic power.