According to this. It’s range was 70km. It was extended to 100km. But doesn’t say how.
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The Barak 8 is a 275 kg missile with a 225 mm diameter (the booster is 540 mm wide), a fin span of 940 mm, and a length of 4.5 m. It is propelled by a two-stage smokeless pulsed rocket motor with a thrust-vectoring nozzle, allowing a flight speed of Mach 2, a range of 70 km, and an engagement ceiling of 16 km, and carries a 60 kg HE-FRAG warhead. Later the range was reportedly increased to 100 km.
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The only explanation I can give is that ;
Hisar-O actually travels at 4 Mach. So uses more fuel quicker. Too conservative specs. Still needs tweaking!
Barak 8 is manufactured so that it is lighter. Hence carries more fuel. It is a next generation missile. So should be more efficient. According to the sites it does have a booster section. Albeit not as large as the ER version.
The Barak 8 is a naval air defense missile system, jointly developed by India and Israel. Design of the Barak 8 is loosely based on the previous Barak 1 missile. Though it uses a more advanced seeker and has extended range.
www.military-today.com
This site too says it is 50-70km range
Barak 8 (the Hebrew word for Lightning) is an Indo-Israeli surface-to-air missile (SAM), designed to defend against aircraft, anti-ship missiles, and UAVs. In January 2007, after several months of intense negotiations, India and Israel signed a US$330 million deal to co-develop an all new...
military.wikia.org
Extended range missile reaches 150km. Recently tested. Has a bigger booster section.
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Barak 8ER is a version with a maximum range of 150 km. Letters "ER" in the designation denote the "Extended Range". This missile comes with a larger booster and is 6 m long opposed to 4.5 m of a standard Barak 8. Some sources report that Azerbaijan operates this extended range system.
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