Choosing a dc step-up type for solenoid

I want to step up 3-5V from an alkaline battery to ~50V to charge a capacitor, the capacitor then provides current to actuate my solenoid.


I am actuating a solenoid powered by batteries for a mobile project. In my tests raising the voltage gets the solenoid to move faster and with a shorter duty cycle. Raising the voltage as high as I want is using too many batteries and adding too much bulk. Right now I am using four 9Vs to achieve 36V and plan to take it even higher.
This is my simple test circuit I have been actuating the solenoid with. https://www.flickr.com/photos/dwest2/4684625445/sizes/o/


I came across a circuit drawing that got me thinking about stepping up the voltage from some lower voltage cells. In theory a few AAAs should provide me with enough power. https://www.edn.com/archives/1995/081795/17di6.htm

This seems perfect, but I will have to redesign around my own requirements. I don't even know if a boost type stepup circuit is right for me. There are so many different types of stepups, I am hesitating about which type would be best for my application. If someone could point me in the right direction and link to a sample circuit, I can go from there. Thanks.

I think I made a decision. I am leaning toward a Step-Up (Boost), FlyBack, Sepic.

SEPIC converters are readily available, provide me with the voltage boost I want, and can even handle currents up to 5A.