SKU: LY3662214
UPC: 011516322142
MPN: 3662214
The Lyman 66 receiver peep sight is a classic flat-receiver aperture sight built for shooters who want better precision out of lever guns, shotguns, and rifles like the Winchester 94, Marlin 336, Marlin 39A, and the SKS. It mounts to the receiver rather than the barrel, which puts the rear aperture closer to the eye and stretches the sighting radius for a cleaner, faster sight picture. We stock the 66A variant (MPN 3662214) for hunters and target shooters who prefer a peep over a buckhorn or open notch. If your gun left the factory with iron sights you've outgrown, this is the upgrade.
Adjustments are where this sight earns its keep. The Lyman 66 uses 1/4-minute audible click micrometer dials for both elevation and windage, so you can dial corrections by feel and count and return to a known zero without guesswork. A quick-release slide lets you remove the aperture for scope use or storage and reinstall it on the same setting, and coin-slotted stay-set knobs hold adjustments under recoil. The sight ships with two interchangeable aperture discs, a large hunting aperture for fast acquisition in the field and a smaller target aperture for tighter groups at distance. Construction is blued aluminum, keeping weight down to about 4 ounces so it won't change the balance of a light carbine. The flat-receiver mounting pattern is the defining fit detail.
This sight makes the most sense on a deer woods lever gun or a slug shotgun where a peep speeds up target acquisition and improves accuracy over open sights without the bulk of an optic. Swap to the large aperture for low-light timber and tight shots, then drop in the small disc for the range or longer shots across a field. Confirm your receiver is the flat-pattern type before ordering. If you're building out an iron-sight setup, pair it with one of our Lyman globe front sights, or browse the full Lyman sight lineup for tang and front options that match your build.
The 66A variant is designed for flat-receiver guns, including the Winchester 94 (pre-angle eject models), Marlin 336, Marlin 39A, the SKS, and shotguns. Verify your receiver is the flat-pattern type before ordering, since angle-eject and other receiver shapes require a different Lyman model.
The Lyman 66 uses 1/4-minute audible click micrometer dials for both elevation and windage. You can count clicks to dial known corrections and return to zero by feel. Coin-slotted stay-set knobs lock the setting so recoil doesn't walk your zero.
Yes. The quick-release slide lets you take the aperture off and reinstall it on the same setting, so you can switch between the peep sight and an optic without losing your zero.
It ships with two interchangeable aperture discs. The larger hunting aperture gives fast target acquisition in the field and low light, while the smaller target aperture tightens the sight picture for precision shooting at distance.
Lyman specifies the 66 as blued aluminum, which keeps weight to about 4 ounces. A few retailers list it as steel, but the manufacturer and most authoritative sources confirm aluminum construction.
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