First is a set of plastic vise blocks for the DPMS AR10 clone.
This allows the upper or lower receivers to be safely clamped in a vise for working on stuff.
And, in preparation for further precision paper-punching, I took the plunge and got a meplat trimmer from Sinclair.
The closed end of a jacketed bullet is the most critical part. For target ammunition, that means the tip is open, because the base of the bullet is the most important factor in accuracy.
But not all bullet tips are created equally, even between two bullets made on the same machine. One source of inconsistency is differences in the meplat. This can be fixed by trimming all the bullet tips to the same shape and length. Here's how it works:
The sharper the tip, the better, but uniform meplats are better still. Long-range (past 500 yards) shooters feel that a loss of less than 2% in ballistic coefficient is more than offset by the increased uniformity.
The main body of the trimmer is Delrin, and it holds the bullet by the ogive, the curved part of the jacket that ends at the pointy end. I found out that I can trim even loaded match ammo, because the case mouth doesn't touch the holder, so the trimming action is the same as if it was just the bullet itself in the trimmer.
In production, the actual depth of cut would be established by the adjustable collar on the cutter, after establishing the proper length desired. Of course, I need to go back to Sinclair to get meplat gauges that will allow me to measure lengths with regular digital calipers.
Still, with bullet holders in .224, .308, and .338 on hand, I could spend many quiet hours in the winter in front of a glowing fireplace, giving my meplats a trim.