Eotech EXPS/XPS Battery Cap Tightness?

[TF82]

The other day at the range I was shooting with my EXPS2 with an Energizer battery that was pretty much new (only used to turn the sight on and off a few times over the course of a couple of months). This was the first time I shot this particular sight and after about 20 rounds it turned off under recoil. I turned it back on and it went a few more rounds then went off again and would not turn back on like before. I changed the battery and tightened the cap down using a coin and it worked fine after that for the rest of the time (about 150 more rounds).

Prior to this the battery cap was hand tight, but tight and when I changed the battery it didn't feel loose, but obviously once I tightened it with the coin I couldn't open it by hand anymore.

I've read that turning off during recoil is an indication of a low battery but this one was pretty new and when I put it back in it turns the sight on without any flashing. I searched pretty thoroughly and can't really find any examples of these sights failing in this fashion like the AA versions would.

Has anyone noticed that these sights can be somewhat sensitive to the tightness of the battery cap or might I have a bigger problem on my hands?

[Ryno12]

I believe the shutting down during recoil were only with the inline AA units.

I have seen only one time where my EXPS suddenly shut down & after removing the battery, I noticed the contacts of the battery itself had an oily residue. A quick wipe clean and it was back to business. Never happened again.
If the battery door is tight & the battery contacts are clean, you shouldn't have any issue.

[markm]

My XPS has a clear stopping point when hand tightening it. There's no ambiguity about it. And when the battery is about to croak, you'll see the reticle blink on and off.

[TF82]

Okay, so it seems like it's probably a battery issue then. Has anyone has problems with Eotechs draining batteries when they're off?

[Boba Fett v2]

Nope. Never experienced any battery issues with EXPS.

[TF82]

Okay, maybe the issue is with the battery and not the sight. I did notice there is a little room for the o ring to move around on the cap and when I moved it all the way back I got that definite stopping point so maybe that was the issue. Either way I won't panic now and I'll try to get to the range again soon to give it another run. Like I mentioned, after the battery change/coin tighten it worked fine.

[HD1911]

That O-Ring still in good shape?

[Hmac]

EXPS2 reticle will flash under recoil if the battery is low.

Failure
: The reticle is flashing/ flashing on and off/ unit turns off during recoil:
Corrective Action 1
: This is the low battery indicator. Replace the battery.

Corrective Action 2
: If the battery is low, a high recoil weapon platform can cause the
reticle to flash on and off, even before the low battery indicator takes effect. Replace
the battery

[TF82]

HD1911, it looks fine. I was thinking maybe it was out of place and creating some tension as I screwed it in that led me to believe that it was tight when it wasn't.

Hmac: I did see that, but what strikes me as odd is that the battery was an Energizer that I bought at Target (not from the Internet) only about a month before taking it to the range. Even if I turned it on for an hour a day, which I had not, there was no way it should have been low at that point. That was why I was wondering if there were any issues with Eotechs draining batteries when off.

Like I mentioned, I'm wondering if it could have been a bad battery. What is weird though is that when I install it, it still turns the sight on and doesn't flash at all.

[HD1911]

HD1911, it looks fine. I was thinking maybe it was out of place and creating some tension as I screwed it in that led me to believe that it was tight when it wasn't.

Hmac: I did see that, but what strikes me as odd is that the battery was an Energizer that I bought at Target (not from the Internet) only about a month before taking it to the range. Even if I turned it on for an hour a day, which I had not, there was no way it should have been low at that point. That was why I was wondering if there were any issues with Eotechs draining batteries when off.

Like I mentioned, I'm wondering if it could have been a bad battery. What is weird though is that when I install it, it still turns the sight on and doesn't flash at all.

Gotcha. Glad it's G2G for ye. I would place the odds of getting a Bad New Battery over getting a Bad New Eotech EXPS.