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Check out this schematic please and help to choose IR LED distance-wise

Hi guys,

I'm making a light barrier and working on a "sender" part right now. The main thing I want to achieve is the maximum distance. I'm using Vishay TSSP4038 (see receiving signal. In the datasheet it's stated that it can work on distances about 30m. I can't get even close. With 350mA (1W) LED it's about 3m max (outdoors).

Here is my current schematic: 


T1 is 
NPN transistor. Q2 is N-channel mosfet. LED power schematic is taken from this instructable.

ATTINY25 turns the LED on/off 38000 times per second (kHz). So effectively I can double max current through LED (change R3 to 2.5). I also have some 1W chinese LEDs from ebay, which do work better (distance-wise), but I'm not sure how much more current I can give them without burning.If you think that the transmitter is good then should I provide receiver details ?

I would be very thankful if someone better than me in electronics would check the schematic and maybe give me some advice or tell if something is really wrong.

A huge thanks.

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