Why we exist
GMI was founded by mechanical engineers who design and build precision tooling for industry. We bring that same discipline to every swaging die: hardened tool steel, ground to size and measured before it leaves us.
Every die that leaves our facility is precision-machined, carefully finished, and verified for dimensions, function and consistency. In precision shooting and slug production, the barrel does not forgive poor alignment, inconsistent sizing or careless manufacturing.
What we make
Our calibre range runs from .177 to .457, covering everything from competition field target shooting to big-bore airgun applications and commercial slug production. Whether it is a single custom die or a complete slug-making system, our focus remains the same: accuracy, repeatability and long-term performance.
Our SlugMaster kit is patented for its auto-bleed and adjustable hollow-point system — innovations developed from real shooter feedback and practical production needs, not from what was easiest to manufacture.
Who we make it for
At GMI, we believe the ability to make something on your own is a powerful expression of freedom, self-reliance and enterprise. Our products are built not just to make slugs, but to help people create, experiment, improve, and even build their own precision slug-making businesses.
For the last 6 years we have empowered shooters in the USA, Europe, Australia and beyond to make their own slugs, and some of them now run their own slug-making businesses on GMI tools.
If you have a question about a setup, a size or an order, message us. We answer on WhatsApp and by email.
Talk to the people who make the dies
Tell us your calibre, press and target slug weight. We answer on WhatsApp and by email.