Looking for a different way to trim? A faster way to convert .223 to .300 Blackout? The Mark 7 Power Trim Xpress is the answer!
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About the Power Trim Xpress
Both Lyman and Mark 7 offer the Power Trim Xpress, a press-mounted electronic case trimmer for progressive, automated, turret and single-stage presses. This time-saving machine also trims and case forms .300 Blackout from .223 brass!
From Mark 7:
Works on most Progressive, Automated, Turret or Single Station Presses
Our new Power Trim Xpress case trimmer will tackle the toughest commercial trimming jobs yet is priced to fit any reloaders budget. The trimmer features a powerful variable speed DC motor. The motor is often found on industrial CNC equipment, so you know that it is a tough work horse, yet it is also a slim design that takes up minimal room.
The trimmer will speed through standard trim jobs as well as easily handle cartridge conversions such as 223 to 300 Blackout.
The trimmer will accept standard trim dies and is equipped with a vacuum manifold to cleanly evacuate chips. In addition, the trimmer comes with a long-lasting carbide cutter. (Note: some photos show additional items not included with product. Product includes: Trimmer, vacuum manifold, motor, power cord and mounting hardware.)
What’s in the Box
Included is the power supply with variable speeds, vacuum adapter, motor assembly, adapter flange, mounting screws, power cord, and 2-flute ⅜” solid carbide end mill.
It does not come with a trim die or extended shellholder.
Set-Up and Use
I opted to set up the Power Trim Xpress on a Lyman Victory single-stage press.
I secured this on an Inline Fabrication Ultramount on the Ultimate Reloader Bench System and added an extended shellholder and .300 Blackout trim die.
I sized a few .223 cases to roughly position the die and checked with a Sheridan slotted case gauge to see where the shoulder was at. (Remember, not all .300 Blackout gauges are created equal! Lyman case gauges are also to SAAMI spec.)
Next, I installed the cutter to the motor, the motor to the trim die and connected the power. Before clamping the motor down, I needed to position it appropriately. There is 0.050” drop for each turn of the motor down into the die and I needed to come down 0.156”. I did an initial cut, measured, and adjusted, using calipers as it got closer. (I zeroed the calipers on factory brass.)
I also verified the shoulder bump and trim length with a Hornady headspace comparator and compared it to factory ammunition. The vacuum adapter was the last addition after all was verified. Trimming went smoothly!
Conclusion
I was primarily concerned with quickly converting .223 to .300 Blackout. The Power Trim Xpress did this wonderfully! It’s also incredibly versatile, compatible with both single-stage and progressive presses.
Get the Gear
The Power Trim Xpress is available directly from Mark 7 Reloading and Lyman.
Also watch Midsouth Shooters Supply!
Lyman Pro Trim-Die .223 at Midsouth Shooters Supply
Lyman Pro Trim-Die .300 Blackout at Midsouth Shooters Supply
Sheridan Engineering .300 Blackout Gauge
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Thanks,
Gavin Gear
