Forster 284 Neck Tension Gage

Forster Neck Tension Gage: Essential Reloading Quality Control

The Forster Neck Tension Gage is a straightforward but invaluable tool for any serious reloader. It bridges the gap between case preparation and bullet seating by giving you objective data about your brass.

How It Works

After you've sized your case necks and before you seat bullets, insert the stepped end of this gage into the case neck. The tool features four precisely machined diameters that increase in size, each etched with its measurement. Slide the gage in until one diameter achieves a slip fit—that's your inside neck diameter reading.

Why It Matters

Consistent Neck Tension — Uniform neck tension across your batch ensures consistent bullet release and improved accuracy. Variations in neck diameter lead to variations in bullet seating force, which translates to velocity variations downrange.

Defect Detection — The gage reveals whether a "donut" has formed at the neck-shoulder junction—a common problem that compromises case integrity and can cause dangerous pressure spikes.

Fine-Tuning Your Process — Once you know your actual inside neck diameters, you can adjust your sizing dies or neck-turning equipment to achieve the precise tension your loads demand.

Built to Last

This is a simple, durable tool with no moving parts. The stepped design and etched markings ensure years of reliable use in any reloading shop.

Available in five calibers to match your specific reloading needs.