Anyone know of such a beast? I have a few ideas for a project that could use one of these. I know the PAR20 and PAR30 lamps are open rated but I'm wondering if they made the any non reflectored open rated models. As far as my knowledge, no one makes a 35/39w CMH in the ED17 envelope nor do any G12 based 35/39w CMH lamps exist.

Here's a G12 35w CMH . It's not open rated though :
https://www.ebay.com/itm/New-Hg-Ceramic-Metal-Halide-Lamp-CMH-T6-830-G12-35-Watt-HID-Bulb-ISO-9001-14001/303171377744

Thanks, but yeah it seems like my hunch is right. It's nearly impossible to find a open rated 35/39w CMH lamp in a non reflector format.

I use standard G12 or G8.5 lamps enclosed in vapour proof fixtures for table lamps and such. A bit bulky but I have never found or experimented with something smaller...

Yeah I was thinking that a scaled down vapour tight globe would be perfect for enclosing a G8.5/G12 lamp without it being too bulky.

I have only ever used 150W incandescent vapour proof for 20W or 35/59W CMH. I have thought about smaller vessels, but my ideas seem to run dry. Maybe a small Mason jar would work, but I haven't gotten around to it. I'd like to have a 20W in a glass chimney table lamp with a shade over it, but I need to find a bottle that is strong enough yet small enough to go into the chimney. Also, a small Mason jar would most likely fit properly in a conventional harp for a standard lamp shade, too.

 How about a empty spice bottle ? They're maybe 1" wide .

Well, if they can take the heat and I could find a suitable metal cover, that would work.

Yeah that might work, especially with the lower wattage lamps that shouldn't get too hot.

I would certainly not exceed 35/39W with a spice bottle. 50W lamps and above are available in ED17, so I would use that for higher wattage.

Slight bump, but there is this one lighting manufacturer that I think might make what you are looking for. They have a lamp listed in their catalog as being a 35 watt metal halide lamp with a medium base, while making no indications that it's a reflector lamp. I have no idea what the lamp actually looks like and the picture is obviously wrong. This same company has 35 watt metal halide listed as an option on some of their fixtures so I kind of wonder if it's a proprietary thing. I've known about these for a few years and have always been curious to know what they are actually like. For all I know, it's just a standard quartz lamp but in some weird 35w size.
Here's a link to an Amazon listing, but it's kind of expensive at $49.

https://www.amazon.com/Dabmar-Lighting-DL-MH35-Medium-Halide/dp/B01L8Q4JME

Here's the catalog "page" where it's listed.

http://dabmar.com/specs/DL-MH35-DL-MH1000_SPECS.pdf

There's also a dual arc version available apparently, and I suspect the image on this one might actually show the dual arc version of the 35w lamp, and it looks like it's quartz and not CMH. Still would be really interesting to have one though.

http://dabmar.com/specs/DL-MH35-DA-50K-DL-MH70-DA-50K_SPECS.pdf

Interesting find. The twin arc tube 35w looks really interesting. Too bad it's so expensive though. 

Interesting find. The twin arc tube 35w looks really interesting. Too bad it's so expensive though.

It is expensive because it is a niche product. Plus I somehow doubt the dual arctube would do much except fast hot restrike, because MHs tend to leak arctubes at EOL and so cause glow discharge in the outer. I'm afraid in that case the glow discharge will shunt the ignition pulse to a too low voltage for tye other tube to ignite and take over.
But in fixtures like wall packs or bulkheads you may get the same effect by just using two sockets and connect two regular lamps in parallel, it will become cheaper...

It is expensive because it is a niche product. Plus I somehow doubt the dual arctube would do much except fast hot restrike, because MHs tend to leak arctubes at EOL and so cause glow discharge in the outer. I'm afraid in that case the glow discharge will shunt the ignition pulse to a too low voltage for tye other tube to ignite and take over.
But in fixtures like wall packs or bulkheads you may get the same effect by just using two sockets and connect two regular lamps in parallel, it will become cheaper...

A y-shaped socket adapter can replicate such effect pretty well.

A y-shaped socket adapter can replicate such effect pretty well.

Yes, but where to find a porcelain pulse rated one ?