Lyman Great Plains Rifle .50 Cal Percussion, 32 in Octagonal Barrel, 1:60 Twist, Walnut Half-Stock, Double-Set Triggers
This Lyman Great Plains Rifle in .50 caliber is a classic percussion muzzleloader built by Investarm in Italy and marked for Lyman, Middlefield, Conn. It features a full-length 32 in octagonal barrel with a factory 1:60 twist optimized for patched round ball, a color case-hardened sidelock, and walnut half-stock with steel furniture. A traditional rear sight setup is installed as shown, with provisions for alternate sighting options.
Traditional details stand out on this example: a drum/snail bolster with external hammer, double-set triggers, two transverse wedge keys with oval escutcheons, and an under-rib with two pipes securing the wooden ramrod. Markings include "LYMAN - MIDDLEFIELD - CONN." and "GREAT PLAINS RIFLE .50," plus "MADE IN ITALY" over "BLACK POWDER ONLY" with the Investarm boxed "I" mark. Per factory references, overall length is approximately 49 in and weight is about 9.25 lb.
The rifle uses #11 percussion caps on a 6x0.75 mm nipple thread. Sighting is handled by a dovetailed front blade and the installed rear sight as shown; the rifle supports traditional Lyman sighting options, and an alternate rear sight is included.
Condition
Overall Condition: Excellent condition, showing only faint signs of any prior use or handling.
Bore Condition: Excellent - Clean, mirror finish, no signs of wear.
Bore Rifling: Excellent Rifling - Sharp lands and grooves.
Specific Condition Notes: Minor scratches and small blemishes are present on the exterior surfaces.
What’s Included
- Wooden ramrod with brass tip (installed)
- Wooden short-starter with brass tip
- Alternate rear sight body (primitive/fixed style; 3/8 in dovetail)
- Sighting setup as shown (see photos)
- Original Lyman Great Plains Rifle factory box (orange)
- Lyman Great Plains Rifle paperwork/manual
The 32 in octagonal barrel measures approximately 15/16 in across the flats and is secured to the stock by two wedge keys. The under-rib with two pipes and the included ramrod make loading straightforward. Steel trigger guard, buttplate, and nosecap complement the walnut stock’s satin/oil finish for durability in the field or on the range.