This sounds stupid from the title but whatever 
I have a 50 watt Philips CMH.
I currently do not have ballast for it, and I am planning on finding a way to run it on some controlled power source, which is where the dimmer comes in.
I have a Lutron MAW-600 dimmer for incandescents. It doesn't really like LEDs, it leaves them slightly lit when turned off.
Maybe if I set my dimmer to the lowest position with this metal halide bulb (With no ballast due to the fact I can't find a fixture or ballast anywhere currently), it (45% chance) may either be underpowered, or it MAY work perfectly.


The picture is of the bulb in question, when it was still sitting at the ReStore (The one I went was extremely overpriced)


I do not plan on going this way permanently, only until I find a good fixture and/or ballast for it.

I'm no expert, but I don't believe it won't turn on at all with just a dimmer. It shouldn't fry the dimmer either, but you're better off just waiting until you get a proper ballast to light it.

All low wattage metal halide lamps require about 1000 volts to strike. The circuit you propose here will not allow ignition. Otherwise, a dimmer is not a substitute for a ballast. I wouldn’t try it even if I could make the lamp strike.

The 1000 volts are not supplied directly from the ballast but use an ignitor to strike the lamp. The ignitor shuts off when the arc has struck (it doesn’t have a function other than during startup).

They need > 3.5kV in fact to ignite, so no way.

You need a magnetic ballast with at least 220V open circuit voltage + 3.5kV MH ignitor, or better an electronic ballast. As commercial lighting (sadly) is moving away from discharge lamps, surplus electronic ballasts are cheap/easy to find and work well.

 Here ya' go ! : https://www.ebay.com/itm/325569682126  $28 with free shipping !

Looks nice. But I have to admit here in the European part a modern 50W electronic ballast by Philips weights may be around 150g and just fits on a palm The price for NOS was about the same.

Electronic ballasts will never last as long as a pile of steel and copper.

Yes. Kinda... But I have a small pile of Osram Powertronics for 70W MH from around 2008-2010. They look that they were in daily use until replaced with LEDs about 1-2 years ago. So more than 10 years in use in a hot ceiling, but still ok. Also, N3210 wanted just to play with a lamp. For home use, small neat electronics are just more fun (IMHO).

This sounds stupid from the title but whatever 
I have a 50 watt Philips CMH.
I currently do not have ballast for it, and I am planning on finding a way to run it on some controlled power source, which is where the dimmer comes in.
I have a Lutron MAW-600 dimmer for incandescents. It doesn't really like LEDs, it leaves them slightly lit when turned off.
Maybe if I set my dimmer to the lowest position with this metal halide bulb (With no ballast due to the fact I can't find a fixture or ballast anywhere currently), it (45% chance) may either be underpowered, or it MAY work perfectly.


The picture is of the bulb in question, when it was still sitting at the ReStore (The one I went was extremely overpriced)


I do not plan on going this way permanently, only until I find a good fixture and/or ballast for it.

Do not even try anything like that.

If you would be lucky, the lamp won't ignite (as it requires 1500V or above for a reliable ignition).
But if the lamp happens to ignite (even when very rare, it may happen), you will get big BOOM from essentially a short circuit, destroying both the lamp and the dimmer.

Dimmer is essentially just a switch, so it won't limit the current in any way, it just controls how long the lamp is connected to the mains, so just the duty ratio. It assumes the current to be still limited by the load resistance, so the duty ratio just get translated to how much average power is being delivered to it. So it works only with resistive and maybe inductive loads (with inductive the timing results into varying current, but only if the dimmer control still works correctly with that).
For discharge ballasting you really need an element limitting the current, so an inductor or for some cases a resistor.

All low wattage metal halide lamps require about 1000 volts to strike. The circuit you propose here will not allow ignition. Otherwise, a dimmer is not a substitute for a ballast. I wouldn’t try it even if I could make the lamp strike.

The 1000 volts are not supplied directly from the ballast but use an ignitor to strike the lamp. The ignitor shuts off when the arc has struck (it doesn’t have a function other than during startup).

Actually, ignitors with a pulse voltage of 1000v and below are specifically designed for striking probe start metal halide lamps and Philips HPI metal halide lamps on European 220v-240v mercury vapor series choke ballasts. As RRK said, the ignitors for low wattage pulse start metal halide lamps and all other pulse start metal halide lamps typically have a pulse voltage between 3500v and 5000v because a 1000v pulse voltage is insufficient to ignite a pulse start metal halide lamp.

You may be able to use a 50W incandescent lamp in series with the MH bulb, but the circuit would have to run on 240V. Personally, I have never seen a 240V 50W incandescent lamp here in the USA. You might have to import one from Europe, or some other mainly 240V place. After that, you would need to find a way to provide a pulse of a few kV. An ignitor is cheap, so you could just buy one of those. One annoyance of this circuit is that you will need to find a 240V power source. A dryer plug will do. I believe this circuit will end up drawing 100W of power. Take this all with a grain of salt, as I am not very experienced or learned in the broad field of electrical engineering.

I've never seen a 50W incandescent lamp here, either. They mostly went from 40W to 60W.

The usual ratings were 15, 25, 40, 60, 75, 100 & 150W. Occasionally 200W but that was it for the most part.

Not sure about 240v 50w incandescents, but 50w 120v incandescents used to be almost exclusively the rough service type. I suspect the wattage was bumped up to 50w in order to maintain a similar output as a 40w general service incandescent.