UPDATE 1-Taser 2nd-quarter loss narrows

* Q2 loss/shr $0.01 vs $0.03 year ago

* Revenue up 4 pct

* R&D expenses jump 45 pct

July 29 (Reuters) - Stun-gun maker Taser International Inc (TASR.O) posted a narrower quarterly loss helped by new product development efforts as it moves from a products company to a full solutions provider. Second quarter net loss narrowed to $723,403, or 1 cent a share, from $2.0 million, or 3 cents a share, a year ago. Revenue rose 3.5 percent to $21.8 million. Gross margin, however, fell to 63 percent.

Analysts on average were expecting the company to post a loss of 4 cents a share, before special items, on revenue of $19.1 million, according to Reuters Estimates.

Research and development expenses rose 45 percent to $4.4 million, driven by development efforts on multiple new products.

The company's Taser guns, also known as conducted energy weapons, incapacitate people through a 50,000-volt jolt of electricity.

Shares of the Scottsdale, Arizona-based company closed at $5.55 Tuesday on Nasdaq. (Reporting by Bhaswati Mukhopadhyay in Bangalore; Editing by Savio D'Souza)