Hey gang. I've taken it upon myself to update/expand the parts weights database. I'd like to add tac lights and mounts to it, but right now the selection in the database is pitiful. I have like 20. If you have a tac light or a mount, ANY kind of tac light or mount, and you own a decent scale, could you take a measurement and post in this thread? No batteries. Weights in oz if possible, but google can convert anything for me, so I'll take what I can get. Just need make, model, and weight. Thanks in advance for the data!

google sheets

I've got another mount that's out for delivery right now.  As soon as it arrives I'll weigh my light (Inforce WML, sans battery), and both mounts (Magpul offset and Magpul cantilever) on my wife's kitchen scale.

Got it!  Here ya go:

Inforce WML, White, Gen. 2: 2.6 oz.  (3.1 oz. w/incl. CR-123 battery)
Magpul M-LOK Offset Light/Optic Mount, Aluminum: 0.6 oz. (w/M-LOK mounting hardware)
Magpul M-LOK Cantilever Rail/Light Mount, Aluminum: 0.8 oz. (w/M-LOK mounting hardware)

Awesome! Thanks amigo. I'll add them to the database asap. Who else wants to help out their fellow arfcommers?

Surefire m300 300 lumen and Stream light RM1, each with battery, but without mount, weigh an identical 3.3oz

Sweet, that's two more. Who else can help?

Arisaka/Malkoff, single cell, no mount or battery, 61g or 2.15 ounces.

Fantastic! They're all going in the database later today. Who else wants to help out their fellow arfcommers?

Lumens factory E head, Ariska 300 body with pressure switch and 5" cord - 3.17 oz - with clicky - 2.64 oz
Surefire Ke1A head, Ariska 300 body with pressure switch 5" Cord - 3.52 oz  with clicky instead, 2.99 oz

don't have any mounts for these, so this is bare body with different lamp and switch combinations.

on a side note, don't bother saving weight with the lumens factory head on a single cell light. its pretty anemic .

awesome, I've added all of the above to the database. Thanks a ton guys! Anyone else want to help the cause?

I've got a 600U without mount, two versions of Arisaka MLOK mounts, X300/X300U and a G2X I can throw on the postal scale when I get home from work.

ETA:  You want with or without batteries?

I'd prefer without, I have battery weights listed separately in the database for anyone that wants to know a rough total, but since battery weight can vary a bit, measurements w/o batts are best. Thanks much!!

Surefire
X300V-A (150 lumen version with the Lever latch) - 2.85oz (81 grams)

Elzetta
High/Low tail cap - 0.7oz (19 grams)
Bravo Body - 2.05oz (58 grams)
AVS Head - 1.85oz (51 grams)
Flood lens - 0.3oz (9 grams)
Crenulated Bezel - 0.3oz (9 grams)

added! We're really making some progress. Tonight I'll go through all the Surefire data that they have posted on their web site. Elzetta is another good one to include. Any other brands that are pretty popular right now that I should look into?

I've got an old metal bodied Surefire GZ2 that weighs 5.3 ounces with the lanyard.  4.8 ounces without the lanyard.

awesome, thanks for your contribution! I'll add the data ASAP!

Can you clarify whether you're talking about weapon-mount lights only?

'Tactical' is really subject to interpretation.

For example:  I just bought a Nitecore MH20GT.  Very compact, bright, with 'tactical' features.  4.9 oz. with single 18650 battery.
It could be mounted on a gun, but it doesn't have a tactical tailcap (or even a tailcap switch at all.)  I use it for EDC, and have no plan to affix it to any of my guns.

I would, in this case, say that I'm referring to lights that people would mount on a gun...do people put lights on guns that have neither a tail cap or tape switch option?

Surefire m600P fury 4.8 Oz
Surefire M620 on LT270  4.3 Oz
Surefire M300 3.6 oz
Surefire M600V 3.3 oz

All without batteries

I have a 952V around here somewhere.....

ETA surefire m952V on haley mil620 mount 6.6 oz

ETA2: I'll dig around my drawer/boxes o' parts tomorrow, I'm pretty sure I have another couple lights floating around

awesome, thanks amigo...all the data posted thus far has been added. Anyone else?

How do I view input? I see the "rules" but can't locate data w/ scrolling, etc. Thanks.

At the bottom of the page there is a horizontal row of tabs for the different sheets. To the right of that there are left/right arrows that allow you to scroll through the tabs (sheets, technically, but it's the same thing). "Lights" are second to last, so they are to the 'far right' on that row of tabs. Let me know if I that isn't helpful.

Thanks. That worked. Didn't notice it earlier. You have quite the database going there. Very nice.

thanks. It's still sort of in it's infancy. A lot more data will be added soon. Sheets on BCGs and gas blocks are the kind of level of detail I'm shooting for everything to have eventually. It's been a labor of love in a way, but hopefully, over time, sufficient contributors will add their own data and it'll become, eventually, self-sufficient / updating. That's the dream anyway...

Surefire M300v with KM1A lens on a BCM Keymod adapter:                  2.9 oz
Surefire M300 mount alone (no light):                                                 0.8 oz
Surefire M920v mount alone (no light):                                               1.7 oz
Haley Strategic Thorntail M620 Light mount alone:                               1.0 oz
Surefire M920v with KM3 lens, Thorntail Keymod Adapter:                    6.4 oz
Surefire M920v with KM3 lens, stock Surefire Mount:                            7.4 oz
Surefire M300v with KM1A lens & Larue LT752 Mount:                          4.1 oz
Surefire M300 with KE1F lens & BCM Keymod Adapter:                        3.4 oz

You can probably extrapolate some of the mount weights from the data here.  I used my postal scale downstairs, made sure to remove the batteries, etc.

And I found a Haley Strategic mount for the Surefire M952v that I needed for my AR15A4, so winning.  Go down in the basement, weigh some lights, find the needed mount!

Somewhere around here, I have a Thorntail keymod adapter that's not attached to any lights.  If I find it, I'll make sure to get the weight.

Now, to put rifles back together!  

Awesome! Thanks for posting this. It helps!!