Questions about Surefire C2

berry580

Flashlight Enthusiast
Joined
Oct 17, 2008
Messages
1,138
Location
Sydney, Australia
I want to know whether this would fit a SureFire C2? I asked the seller, he said it'll fit the SF 6P and 9P, so does that mean it'll also with the C2 or not?
I want to use my C2 in a 2x18650 format, if the Solarforce extension doesn't fit the C2, does anyone know what would fit?

My C2 currently has a z41 tailcap, i know about SF's click-on lockout feature and i couldn't momentarily press the tail button in regardless how the much the tailcap is loosened/tightened on the body, so should it allow momentary on or not when without a drop-in installed? I just have this stupid fear that after i buy the drop-in and have everything ready, the tailcap may turn out to be faulty... lol
 
I have used that extension on my M2, which is the same body as the C2 so YES it will fit the C2 body.

I can't comment on its use with the stock Z41 though, since mine is modded.
 
It should fit. Any part that is for a 6P will fit a C2. The threads on the tail and head are the same. Is your C2 already bored to fit 18650 cells? If not all you will be able to fit is 17670 size.

I am not sure what you mean about your tailcap. It should currently have momentary and twist for constant. Are you saying yours is broken? Surefire will replace it if that is the case. Z41s are just about bulletproof.

Zach
 
My C2 currently has a z41 tailcap, i know about SF's click-on lockout feature and i couldn't momentarily press the tail button in regardless how the much the tailcap is loosened/tightened on the body, so should it allow momentary on or not when without a drop-in installed?

The z41 has no 'click on' feature.

Does the light come on when you screw the z41 on fully?

If it does, you should be able to back it off until the light goes off, then a momentary press of the button should turn on the light. There is no click.

If it does not behave like this, it is broken.
 
It fits and the Z41 works 100% on the end.

The only hassle I see is that the tube hits the outer edge of the C2 before the inner contact ring is touched.
Meaning that any contact is made through the threads rather than on the surface made for this.
Mine does this on 6P, 6PD, C3, L2m and even a slight gap on a full sized L2.
These extensions are thread contact only it seems.
By turning 1-2mm off the end it will make contact on the rim like the tailcap does. It does make for good looks outside as there is absolutely zero gap.

You will of course need to bore the C2 out to take the 18mm cells, but the extender is good.

I use the 1xCR123 extender with the same thread contact issue on my personal protection 6PDL and the Z59, I trust it with my life.
 
First of all, thank you everyone above with all the help/recommendations/opinions/information provided.

So the Solarforce extension fits on the C2, that'll be perfect, 2x18650! :twothumbs

Yes, my C2 is bored to accept 18650, so I won't have any issues taking 18650s.
Well right now, my C2 doesn't have a drop-in, and the z41 tailcap cannot wouldn't move AT ALL. What i mean by that is it wouldn't even allow 'momentary' activation regardless how it twist the tailcap relative to that indentation on the body. If I try push the tailcap button, it feels like a solid hard rock, I have no idea whether its broken or not, but there's no rattling.
Any idea, anyone? :thinking:

Drop-in.... i don't know, but i do fancy good regulation. But now that I can use the 2x18650 format (i'm planning to use 18650s exclusively), i believe many drop-ins will offer good regulation.
Any good money for value recommendations? (i.e. not looking to pay $50 for a drop-in)
 
I would check Nailbenders thread. 2 18650's will give you a ton of runtime with whatever you choose. How bright are you looking for? A Malkoff M60 would go awhile in that setup. As far as the tailcap it might be toast. I would try some light banging on it!! If that doesnt work call surefire for warranty. Or else get a mcclicky kit and just upgrade it yourself.
Zach
 
Well right now, my C2 doesn't have a drop-in, and the z41 tailcap cannot wouldn't move AT ALL. What i mean by that is it wouldn't even allow 'momentary' activation regardless how it twist the tailcap relative to that indentation on the body. If I try push the tailcap button, it feels like a solid hard rock, I have no idea whether its broken or not, but there's no rattling.
Any idea, anyone? :thinking:

You mention that your C2 has no drop-in currently installed. Without a drop-in (or with one but without batteries), the momentary switch on the C2 or 6P etc doesn't do anything. It needs the pressure on the spring so there is something to actually push down on. With a drop-in at one end, and some batteries in there, you should find it is fine.

If you want to simulate this to test, remove the head from the C2, put in 2 xCR123A or 1x18650, then hold you thumb over the head end and put some pressure down on the + end of the battery. Keep that pressure (simulating the spring of the drop-in), put the tailcap to fully tight, unscrew a 1/4 turn or so, and then try the momentary switch.

Obviously nothing will actually happen, but you will at least feel the switch pushing in and springing back out as you release.
 
Last edited:
I would check Nailbenders thread. 2 18650's will give you a ton of runtime with whatever you choose. How bright are you looking for? A Malkoff M60 would go awhile in that setup. As far as the tailcap it might be toast. I would try some light banging on it!! If that doesnt work call surefire for warranty. Or else get a mcclicky kit and just upgrade it yourself.
Zach
well brighter the better. the C2 light is just my upgradeable toy where i change the drop-in whenever something "better" comes out.

You mention that your C2 has no drop-in currently installed. Without a drop-in (or with one but without batteries), the momentary switch on the C2 or 6P etc doesn't do anything. It needs the pressure on the spring so there is something to actually push down on. With a drop-in at one end, and some batteries in there, you should find it is fine.

If you want to simulate this to test, remove the head from the C2, put in 2 xCR123A or 1x18650, then hold you thumb over the head end and put some pressure down on the + end of the battery. Keep that pressure (simulating the spring of the drop-in), put the tailcap to fully tight, unscrew a 1/4 turn or so, and then try the momentary switch.

Obviously nothing will actually happen, but you will at least feel the switch pushing in and springing back out as you release.
i did exact what you suggested, to simulate an installed drop-in.
There is some difference when i push the tailcap, although i think is probably insignificant.

From rock solid (tailcap fully tightened), it allows a 1mm movement when indents on tailcap aligned with indent on body. But it feels around the same compared to when the tailcap is removed from the body and attempted to be pushed in then, feels nothing like the switch being activated.

You think I should be ready to claim warranty? Would i have to send the tailcap to the US?

thank you.
 
Last edited:
I think you might have 2 problems, but not with the tailcap.

Firstly, the simulated pressure might not be as much as you will actually have with a drop-in and battery installed.
There is no way to know that though for now.

Secondly, you might be under a misapprehension of what the momentary switch on the C2 (and 6P etc) actually does. To turn the flashlight on and off, fully tighten the tailcap, loosen it some. To use momentary, fully tighten so it comes on, the loosen it until it turns off. If you just loosen it very slightly you will then only need a very slight press to have it come on again in momentary. If you were to loosen the tailcap say a 1/4 turn, or a 1/2 turn, you would then need more of a press, and you would also feel it more, a definite push in, spring back out.

It is very unlikely that tailcap is faulty, although it can happen of course. This is not because Surefire make them so well, but because there isn't really anything to fail. Other than stiffness or something actually stuck up in there like dirt or grit, it's pretty much just a spring.

Try this. Remove the tailcap. Wedge the tailcap between 2 fingers on one hand, and put the thumb of that same hand on the spring inside the tailcap. Now with the other hand, push down on the switch, and push back against that pressure quite hard with the thumb that is on the spring. With pressure on the spring you should be able to then feel the switch pushing in, then pushing back out against you as you release. That's all it is really.

Anyway, do these tests if you want, but overall I'd say is is unlikely you have a fault, other than the mentioned stiffness or grit, which is easily fixable.

If you do have a faulty one, like I said, it can happen, do the following.

Call Surefire, don't bother with email.
Just tell them it doesn't work, nothing happens.
Leave out the part about the bored tube, 18650, aftermarket drop-ins.
I don't know if they would not support you based on those things, but there's no point complicating matters.

If you do that they will most likely just send you a new one.
 
thank you Niconical alot for the detailed help, everything makes sense now.

I actually went a step further and took the tailcap apart and realise this tailcap doesn't have clickie switch so it'll never have what i was initially looking for it order to be considered as"working".

Throughout my flashaholic experience, I've only came across twisty and clickie switching mechanisms. That's probably the REAL problem. This type is totally new to me. I'm surprised I have yet to hear anyone mentioning how different Sirefire "momentary lock-on" switches are. So simply, so stupid, so robust.

From being confused, I've went through being anxious, angry, surprised and now impressed
 
Good to know it's clear now.

You're right about the simplicity and robustness. If you look inside the tailcap you'll see that deeper in, around the base of the spring, there is a metal ring. When pressure is on the spring from the batts, that ring doesn't reach the corresponding end of the body tube (and complete the circuit), unless you tighten it fully, or push down on the switch. That's all it is, pushing the 2 metal parts together manually, hence very little to fail.

Your C2, the 18650 battery and a good quality drop-in and you have something that really can't be beaten. You'll easily find something half the size, twice as bright for a quarter of the cost, there will always be a smaller/brighter/cheaper flashlight, but the C2 will serve you just the same for many years, with of course the option for updated drop-ins as and when you want.
 
Another thing, don't get hung up on the position of indentations on the tailcap and body, they may or may not actually line up somewhere meaningful.
 
Top