Put the paper shims between the lamp pedestal and its guide tube - not between the switch body and battery tube. You want to shim-out most of the side-to-side play of the lamp pedestal.
As mentioned throughout these posts, there are many tricks for getting that pinpoint spot focus. Unfortunately, it takes patience to endure the trial-and-error process usually required with the Mags to get it right.
Most PR-based lamps (including the Carleys) vary a lot in how well the filament is centered relative to the base - and even if the glass bulb looks straight, the filamant varies in position inside the glass from one lamp to the next. All of this kinda stinks.
So, just to summarize a list of my best fixes (based on my experiences) here goes. Please note that there is no priority to the order of the list relative to the amount of improvement. All of them help in most cases, and some are used as a last resort to obtain improvement.
1) Teflon tape the head-to-body threads to minimize head wobble.
2) Trial-and-error (T&E) repositioning (rotating) the reflector inside the bezel until best beam is acheived. [Until someone else mentioned this, I thought I was the only one desparate enough to spend hours trying to find the sweet spot like this...]
3) T&E repositioning of the lamp in the lampholder. Note that not only rotating the lamp may help, but shifting the lamp to one side or another can/will help.
4) For lamps that I can't even get close, I hand-file away a small amount of the bulb flange to allow more freedom to shift side-to-side.
5) Paper shims alongside the lamp pedestal (only if excessive freeplay is evident).
6) "Texturizing" the reflector with clear heat-resistant paint (only if a bit of beam smoothing is desired). Results vary considerably based on application technique, etc.
7) I have sand-blasted (etched) just the lensed end of the Mag Krypton lamps to *help* tame the "grinwurst". Makes them more tolerable IMO. Should work for the Carley lamps as well, though it's not a perfect solution, and again results will vary depending on method/degree of etching.
8) For KPR's that have obviously off-center filaments, I have "flicked" them into being perfectly centered again. Flicking is done by aligning the filament parallel with a flat surface (table) while holding the lamp base with one hand. Place the glass about 1/8" - 1/4" from the surface and carefully, but sharply, flick the glass against the surface using the back of the fingernail. You are essentially "smacking" the glass lamp against the table, thus causing the filament standoffs to bend towards the table. PLEASE NOTE - I use a hard-cover book, or a magazine, several sheets of paper, etc. to provide some slight padding against the table, otherwise I fear that such an impact against a hard surface WILL BREAK THE GLASS! It hasn't happened yet, but it is possible. I can't say whether flicking the filaments like this this shortens lamp life in any way, but I haven't had one blow yet...
8) Lastly, I highly recommend the UCL lenses due to maximim light pass-through. The difference is immediately noticeable once installed.
I'd just like to mention that careful (tedious T&E) of reflector/bezel position and lamp/holder position has yielded an excellent long-throw, near-perfect beam in a Mag 2D with the 805 lamp, (3) Powerstream 1/2D Nicads, UCL lens, and a Mag 2C reflector, using no texturizing or WriteRight. (I don't know why, but the C-reflector does somehow seem to be better...) It throws *very* nicely for a "2D", and has bright run time of about 90 minutes.
Hope this helps -
John
