I just installed a Halo 5" IC remodel recessed can with the 5000P open trim. I installed a 15W R30 CFL bulb, and it hangs down about an inch below the trim. Not very recessed! I have the trim configured properly for R30.
I'd like a bulb that won't hang down past the trim, but produce the same amount of light. Will a PAR30 50W halogen do the trick?
I have those exact cans and they are adjustable. Take out the bulb and remove the trim. Inside you will see two or three wing nuts. Loosen these and raise the level of base to the desired location. If the base is raised all the way up, then indeed your bulbs are too long for the trim you have selected.
Also note that every trim adds a different depth as well. Trims like eyeball sockets are much deeper and may solve your problem. I suspect yours is a flush mount one, and thus the distance to the base is shorter.
To be truthful, I'm not sure about the exact model you are using, but several of the Halo recessed cans have adjustable sockets. Look up inside and determine if the socket assembly is fixed by a couple of thumb screws on a slide rail. If so you can loosen them and set the bulb socket deeper into the fixture. Usually a Par 30 bulb is perfect for these types of fixtures. I do think however, some of the CFL's are longer than incandescent or halogen bulbs because of the elongated ballast neck, especially on some of the cheaper brands. When you go to the store, take the bulbs out of the package and compare the overall length.
They make shorter CFLs. This is one of the down sides of CFLs, that I think a lot of people run into.
I know in my house they hang out of many fixtures, and I have some missing globes on ceiling fans because the bulbs just won't allow the globe to be attached. I guess I'll have to wait 7-10 years till the bulbs die to fix the problem.
You might look for incandescent bulbs of the proper type. Last time I tried to buy some bulbs for one of my fixtures I noticed the CFL version was too long, and I had to go back and round up incandescent versions.
You can go for LED bulbs which have many benefits. LED lights are the best light sources in terms of durability, energy efficiency and color quality. And they are very compact and low profile so they can fit your situation.