n00b question about 50mW

Hello, first of all sorry on my bad english, I'm from Croatia and I have bought green laser XX-852 50mW.
First question is:
Is this laser true 50mW, i measured by ampermeter on the batt. when operating, and it shown 63mW, is that reliable?
second question:
When I start up the laser with my new Trustfire 3.7V battery, the beam is very powerful and strong first 0.5seconds, and then it folds and it's not very bright.
I tought that is because of bad battery and I tried with DC transformer with 4.2 Volts and 1A, and it still folds after about half a second.

Why is that happening.

Thanks on answer.
Mijo

Pozdrav.

Yeah your english is bad

We'll take it over to Personal Messages.

4.2 V is to high.
I think 63 mA is a little low as final current draw.
Your laser is probably dead by now.
Return it or something.

4.2v shouldnt be to high...Most 18650's and alike are 4.2v when charged fully

Guys, let this thread die, it's being taken care of over PM.