A heavy blaster pistol, or heavy blaster, was a more powerful version of the standard blaster pistol.
Heavy blaster pistols were basically cut-down blaster rifles, utilizing a more highly powered gas chamber, firing larger, more damaging bolts with a wider beam. Though bulkier and heavier than a standard blaster pistol, the heavy blaster's advantage was firepower. It had the destructive power of a blaster rifle without the mass and weight of a full length rifle but with greatly reduced range. The power pack was generally the same size as a standard pistol and was consumed at a considerably higher rate than a typical blaster pistol. Due to the weapon's formidable power it was heavily restricted in most systems if not entirely illegal.
The Arkanians were the first to experiment with creating blaster pistols with the same energy output as blaster rifles around 5,000 BBY. It took some time for the concept to be widely adopted, and it wasn't until the time of the Jedi Civil War that power output of heavy blasters around the galaxy began to match Arkanian standards.
ARC troopers, the elite clone troopers of the Grand Army of the Republic, were trained in wielding two heavy blaster pistols at the same time. Han Solo used the BlasTech DL-44 heavy blaster pistol.