Choosing an SCR for Coilgun: Alternatives to BT151-650R for 48V 240A Firing Circuit

Hi, I start this thread saying that this is my first post on this forum and that I'm not english so I could do some grammar mistakes.I'm working on a coil-gun, here's the circuit.
The problem is that I am not able to choose the right thyrsitor, I've tried with a BT151-650R, but it died.I've measured the resistance through the fire circuit, and I got .2-.3 Ohms, then I calculated the max current I could get at 48V and I got 240 Amps.Can you suggest me a cheap SCR which can meet circuit's specs?

Matteo, it is not just the resistance that is in play here but the inductance of your inductor L1.Also, your capacitor is labelled 60 mF.  does that mean 60 microfarads (you can use uF for this) or 60 millifarads = 60 000 microfarads?The BT151 is rated at 12A continuous, but can take short currents of 100A, for 10 ms, so your figure of 240 A may be right or near what is happening.I'd suggest you use a stud mount thyristor if you can find one, they are known to be very rugged.  However they will probably cost more.  You also get TOP-3 case ones which are like a bigger TO-220 like the BT151.it's difficult to recommend a particular thyristor without knowing where you are - you can try Newark/Farnell/Element14, and you can sort on various parameters  including price, but you'd probably find cheaper suppliers.  If you're in Australia I can send you one - I have a few knocking around.You don't need to worry too much about high voltage since you are only using 48V.  But make sure that the thyristor is rated for 50 amps or more, and has a peak non-repetitive current of 200A or more for your circuit.Let us know how you go...