300 BLK trim dies is for the Dillon Power RT1200 trimmer only, and needs a Modified 550, 650 or 1050 toolhead. Single stage OK with an Extended Shell holder. Do not order the die if your not using the Dillon RT1200 power trimmer, dies are wear items, and no replacement when you wear out or break your die. No die rentals(buy die, use die, ask to return your used die as New). If you let your cases spin in the die while trimming, a die might only last 10k cases, non-spinning(don't use to much lube), they last 40K plus. These dies are made from a 300 Blackout reamer and are stamped 300 Blackout. Trim dies do not come with a Lock ring, but you can use a ring from almost any set of dies. Many think the 300 Whisper and 300 Blackout trim dies are the same, but the cases coming out of the dies look DIFFERENT. The 300 Blackout trim dies leaves a sharper shoulder just like 300 AAC Blackout brass, and the neck isn't sized as small vs the 300 Whisper trim die.
Trim dies are $57.95 with $6.80 Priority mail shipping. Both a trim die and 550 or 650 toolhead will fit in the same package. Toolheads can be selected in the drop down menu below with the trim die. Tool heads are available for both the Dillon 550 and 650 Presses for $49.95. These parts along with a RT 1200 Power trimmer ease the pain of making 300 Blackout brass from .223 or 5.56mm new or once fired brass. Once fired Military brass make good 300 Blackout brass. I've had great luck using Lake City cases.
The 300 BLK trim die can also be used with a single stage Press, you just need an extended shell plate to raise the chip window above the top of the Press. This trim die does NOT work with the Hornady LnL AP progressive press, the window to suck away chips is encased within the top frame of the press.
The Threads on the trim dies will fit tight on your toolhead and RT1200, this will help keep your motor square with the case mouth. Oil should not be needed, but might help on tight fits. If you have trouble with a die, I'll offer a replacement vs cash back.
I use a swab with lube to put into the die before use, and the first set I use a little more lube on the cases. The die needs 20-40 cases run through to get BROKEN in!!! Use a Headspace gauge or Case gauge to set Headspace. Once your die is broke in, you can use less lube while trimming cases, you don't want to have the cases spinning in the trim die.
Select trim dies and toolheads from the drop down menu below. 550 toolheads are out of stock
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|Trim die has 3 exhaust ports to carry away the chips. I use the Hornady headspace Gauge to set up the shoulder setback.|