Hornady 366 Parts Diagram Review

He didn’t have a replacement. But the diagram reminded him of something: part #44, the Seater Punch Return Spring. If the spring was weak, the punch would drag. He replaced it with a spring from his spares jar—a generic coil that was 0.002 inches thicker.

The 366 had simply stopped feeling right . The stroke was spongy. The index pawl hesitated. A single #209 primer had failed to seat yesterday, crushed sideways in its pocket like a tiny, silver pancake. That one misfeed meant distrust. And in reloading, distrust meant you pulled the handle again, slower, listening.

He pulled the diagram closer. Under the lamp, the paper had yellowed at the folds. He’d drawn his own notes in the margins over the years: “#27—replace every 5k rounds,” and “#63 (detent ball) WILL fly across room. Use magnet.” The diagram was no longer Hornady’s document. It was Arthur’s diary.

He decided to strip the primer system first. He loosened #58, caught the detent ball (#63) with a magnetic pick-up tool just as his own note predicted, and slid out the primer slide. There—wedged under the slide, invisible to any inspection port—was a flake of crimped brass from a military .45 case. A tiny shard, thinner than paper. That was the sponge in the stroke. hornady 366 parts diagram

So Arthur did what he always did when a machine lied to him. He reached for the diagram.

Arthur wiped the diagram clean of graphite smudges and refolded it along its ancient creases. He slid it back into the manual’s pocket. The 366 wasn’t just a reloading press anymore. It was a map of decisions—Hornady’s engineers on one side, his own repairs on the other. And between them, the trust that came from knowing exactly where every spring, pin, and punch lived.

His gaze settled on the part he’d never needed: the Primer Seater Punch (#43). In the diagram, it looked like a tiny mushroom—a flat face on a steel stem. But the callout box added a warning: “Seater depth adjustable via locknut. Do not overcam.” Arthur had read that note fifty times. Tonight, he realized what it meant. The 366 didn’t have sensors or computers. It had geometry. The punch’s travel was governed by a cam slot in the main shaft. If you over-cammed—if you forced the handle past its natural stop—you didn’t just crush a primer. You bent the punch stem. And a bent stem didn’t show on the outside. It showed in the feel, a year later. He didn’t have a replacement

He traced the primer system first. There it was: the Primer Slide (#39), a tiny steel boat that ferried primers from the drop tube to the seating punch. Next to it, the Primer Slide Spring (#40)—a fragile coil no bigger than his pinky. That , he thought. That’s the liar.

That was the difference between a shooter and a reloader. A shooter saw a tool. A reloader saw a system.

“That’s you,” Arthur whispered to the machine. “Bent stem or a tired spring.” He replaced it with a spring from his

The parts list was not merely an instruction. It was a confession. Folded into the back of the manual, the exploded view showed the 366 as no human had ever seen it: disassembled, weightless, each component suspended in its own halo of white space. The main shaft (#7) ran like a spine through the ghost of the cast iron frame. Around it clustered the cams, the wedges, the wiper arms.

He reassembled the 366 by the diagram’s reverse order. Lower tier, then upper. Cam followers greased. Pawl timed to the shell plate’s detent. When he finished, he dropped a primed case into station one and pulled the handle.

But the diagram told a deeper story. To replace #40, you had to remove the Primer Slide Stop Pin (#41). To reach #41, you had to loosen the Carrier Bracket Screws (#58). And those screws shared a line with the Shell Plate Index Pawl (#53). Everything touched everything else. The 366 was not a collection of parts. It was a grammar of motion.