Support Equipment

KM-1J gunner's quadrant

Also known as
  • KM-1J
  • KM-1J quadrant
  • KM-1J gunner quadrant
  • KM-1J gunner's quadrant

The KM-1J gunner's quadrant is a Croatian M Adler D precision elevation instrument for indirect-fire weapons. Official product data presents it for mortars, guns, rocket launchers, and howitzers, including all MMB17 mortar calibers plus the RAK-SA-12 and LRL rocket-launcher lines.

KM-1J gunner's quadrant, Indirect-fire elevation measuring instrument, Support Equipment
Image source: M Adler D Products Page
Profile / Specs

Profile

Origin
Croatia
Built by
M Adler D
Type
Indirect-fire elevation measuring instrument
Service note
Contemporary
Designer
M Adler D
Produced
Current production

Specifications

Function
Measures barrel elevation and can set firing elements if a weapon's elevation or angle-of-site mechanism is defective
Applications
Mortars, guns, rocket launchers, and howitzers
MMB17 application
All MMB17 calibers: 60 mm, 81/82 mm, and 120 mm
Rocket-launcher applications
RAK-SA-12 and LRL in 128 mm / 107 mm product families
Angular division
1/6400
Elevation range
00-00 to 08-00 lower group; 08-00 to 16-00 upper group
Sighting accuracy
1.5 minutes lower group; 2 minutes upper group
Bubble-level sensitivity
30 seconds
Operating temperature
-30 degrees C to +55 degrees C
Storage temperature
-40 degrees C to +70 degrees C
Device weight
0.9 kg
Complete set weight
1.8 kg
Elevation Instrument Role

The KM-1J is cataloged here as support equipment because the available official data documents its measuring and fire-control-support role, not independent weapon employment. M Adler D describes it as a barrel-elevation instrument that can also help set firing elements when a weapon's elevation or angle-of-site mechanism is defective.

Measurement scale

Official data gives a 1/6400 angular division, lower and upper elevation groups from 00-00 to 16-00, and a 30-second bubble-level sensitivity.

Named applications

The named product applications are all MMB17 mortar calibers, RAK-SA-12, and LRL; guns and howitzers are described more generally as conventional client-inventory systems.

Field envelope

The device is listed at 0.9 kg, with an operating-temperature range from -30 degrees C to +55 degrees C and storage range from -40 degrees C to +70 degrees C.

Compatible Mortars

M Adler D lists the KM-1J as an elevation instrument for mortars and names the MMB17 calibers in its application data.

Compatible itemItem typeCompatibility evidence
MMB17 mortar family, 60 mm, 81/82 mm, and 120 mm smoothbore mortar family, ArtilleryMMB17 mortar family60 mm, 81/82 mm, and 120 mm mortar family

The official product data lists the KM-1J's mortar applications as all MMB17 calibers: 60 mm, 81/82 mm, and 120 mm.

Sources: M Adler D Product Data

Compatible Rocket Launchers

M Adler D lists the KM-1J as an elevation instrument for the company's light and towed rocket-launcher families.

Compatible itemItem typeCompatibility evidence
RAK-SA-12, 128 mm towed multiple launch rocket system, ArtilleryRAK-SA-1212-tube 128/107 mm rocket launcher

The KM-1J application data names RAK-SA-12 in the rocket-launcher category, while the RAK-SA-12 product data identifies the launcher as a 12-tube system available in 128 mm and 107 mm calibers.

Sources: M Adler D Product Data

LRL lightweight rocket launcher, Single-tube lightweight rocket launcher, ArtilleryLRL lightweight rocket launchersingle-tube 128/107 mm rocket launcher

The KM-1J application data names LRL in the rocket-launcher category, and the LRL product data describes it as a single-tube launcher available in 128 mm and 107 mm calibers.

Sources: M Adler D Product Data

Timeline

KM-1J gunner's quadrant Key Events

  1. Current M Adler D product data lists KM-1J applications

    M Adler D's current product data presents the KM-1J as a gunner's quadrant for mortars, guns, rocket launchers, and howitzers, with named applications across MMB17 mortars plus RAK-SA-12 and LRL rocket launchers.

    Sources: M Adler D Product Data

Media

KM-1J gunner's quadrant Images

KM-1J gunner's quadrant, Indirect-fire elevation measuring instrument, Support Equipment - view 1
Source: M Adler D Products Page
KM-1J gunner's quadrant, Indirect-fire elevation measuring instrument, Support Equipment - view 2
Source: M Adler D Products Page
KM-1J gunner's quadrant, Indirect-fire elevation measuring instrument, Support Equipment - view 3
Source: M Adler D Products Page
KM-1J gunner's quadrant, Indirect-fire elevation measuring instrument, Support Equipment - view 4
Source: M Adler D Products Page
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Sources

M Adler D KM-1J Product PagePublisher: M Adler D | Note: Supports the canonical official product URL for the KM-1J; exact specifications are carried in the site's product data script. | Accessed: 2026-07-13M Adler D Products PagePublisher: M Adler D | Note: Supports M Adler D's current product-program context and official KM-1J image provenance. | Accessed: 2026-07-13M Adler D Company PagePublisher: M Adler D | Note: Supports Croatian ownership, limited-liability company status, and manufacturer background. | Accessed: 2026-07-13M Adler D Capabilities PagePublisher: M Adler D | Note: Supports M Adler D's production-program context for mortars, rocket launchers, optics, and supporting fire-control instruments. | Accessed: 2026-07-13M Adler D Product DataPublisher: M Adler D | Note: Supports KM-1J identity, specifications, official image paths, and applications to MMB17 mortars, RAK-SA-12, LRL, and conventional guns/howitzers. | Accessed: 2026-07-13