Hi I can cast a leader of about 10ft without any tangles but a soon as extended more than 10ft I get tangles. I'm using a sonik sk4 aftm7/8 aftm thinking of changing to Greys Xflite or GRXI AFTM6 hoping this might help

Could be lots of reasons, the rod may be the last thing to look at.

1. Is the fly too wind resistant for the leader so the leaders failing to turn it over.

2. Is the leader really limp not transferring the power very well?

3. More likely, is your stop on your forward cast not strong enough leading to a lacklustre forward delivery that's not transmitting the full amount of energy to the loop?

4. Are your loops too big so the air resistence is killing your leader at the last gasp?

5. Are you casting at the water so the leader never gets a chance to turn over?

There are several other little things, but it's probably 3 or 4 I suspect.

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