Forster NR1204 Inside Neck Reamer .20 Caliber (0.2065″)

Description

If you shoot a .20 caliber and you've ever felt a bullet drag going into a fired case neck, that's exactly the problem this little tool was made to fix. The Forster NR1204 Inside Neck Reamer is cut for .204 diameter bullets and measures 0.2065", which is ground roughly .0025" to .003" over max bullet diameter. That extra clearance is intentional, matching the kind of neck fit a lot of reloaders want on a loaded round, and it keeps thick necks from spiking chamber pressure or throwing flyers downrange.

How the NR1204 Works With Your Forster Trimmer

This reamer isn't a standalone gadget. It mounts in the cutter head of a Forster Original, Classic, or Power Case Trimmer in place of the pilot, so if you already run one of those trimmers you're set. You lock a fired case in the trimmer, line up the mouth, and turn the reamer in to shave excess brass off the inside of the neck wall. Timing matters here: reaming is done after the case has been fired with a full load and before you run it through your neck or full-length sizing die.

Why the 0.2065" Reamer Earns Its Spot on the Bench

Forster grinds these from high grade, wear-resistant tool steel, so the cutter holds an edge through a long life of brass prep. The staggered tooth design is the detail folks tend to notice most, since it slices the brass cleanly without the chatter you'd get from a straight-fluted cutter. That means a smoother, more uniform neck wall and better concentricity when you seat bullets.

It's a favorite among .20 caliber wildcatters and precision handloaders who want tighter, more consistent necks than factory brass delivers out of the box. A quick way to check if you even need it: slide a bullet into a fired, unsized case neck, and if you feel interference, that neck's a candidate for reaming. Pair it with your existing Forster trimmer setup and it becomes one of those quiet workhorse tools you reach for every loading session.