Alan:
Can you really imagine an aftermarket PT40 2-section integrated reflector / spring assembly?
I've accepted that I'm stretching the limit in my PT40 with 3.85 V 1.20 KPR's from Top Bulb. The only mfg. site on which I've seen those bulb specs in on OSRAM's web site. Carley says their 3.7 V 1.2 A KPR generates 5.3 mscp = 66 lumen and their 5.0 V 1.2 A KPR generates 8.4 mscp = 104 lumen. I'll assume that my PT40's NiMh's drive the 3.85V bulb at 4.5V and at an interpolated 89 Lumens. I'll accept 89 Lumens as the current limit on the PT40.
A while ago I asked people to comment on the most heat resistant 4AA lights out there, and got little response. I took this to suggest that their aren't many heat resistant 4AA flashlights on the market.
I suspect that the recently posted threads recently concerning DB 4AA's, DB 6AA's, and DB 8AA's have occured because the DB platform appears to offer the most flexible potential of commercially available underpowered lights for modding heat generating high wattage lamps and driving them with AA's, 123's, or 4/5 A cells.
Other threads relating to putting higher voltage and wattage output into Mag 2D and mag 3D's with 123 NiMh packs are also driven by a desire to generate more lumens from reasonably sized and priced heat tolerant commercially available products.
Having said that, it sure would be great to have a PT40 with an aluminum reflector and a lens that was far enough away from the halogen bulb nipple so you and I could run hotter Halogen lamps than the .50 amp OEM lamp. In the meantime, I will look elsewhere when I want > 89 lumens.
On the other hand, I reported a while ago that I was aftaid that the heat of my Carley 3.7 V 1.7 A Krypton Star would soon destroy the PT40 reflector. I haven't tried the Carley KSR 3.7 V 1.5 A bulb. This 1.5 amp bulb should generate 115 Lumens in a PT40. Maybe I'll try one just to see if my PT40 can survive running consistently at a level brighter than either my 8X or a 3-cell P90. I don't, however, want to consider risking the destruction of the PT40 until I've finished pushing the lumen limits on larger and higher potential DB's and Mags.
Until then, my PT40 will have to settle for being the the brightest light I know at it's size or less that doesn't run a P61, P90, or P91. If I push the PT 40 harder, the only LA I might beat without damaging the PT40 is the P90.