Help with Aimpoint

[260 Rem]

Purchased this T1 about 3 years ago ...decided to change battery, and can not remove the battery cap. I have contacted Aimpoint but no reply yet. Looks like the battery cap is either cross threaded or perhaps the O-ring has slipped into the threads...but whatever, is frozen solid. I have tried with vise grips over tape on the outer ring (but need to be real careful not to distort), and a coin in the slot with a wrench. No Luck. I am thinking a hose clamp on the outer ring might help a bit, but.... any suggestions?

[Rancid Crabtree]

If your able to get a replacement cap it may be best to split the cap. Forcing it to unscrew could pile up the threads and ruin the housing.
Slot the top of cap thru with a hacksaw blade. Then use die grinder to groove the sides just shy of hitting the threads. Then use a chisel in the hacksaw groove to separate the halves.

[260 Rem]

I see Brownells sells replacement caps ... maybe mine is not an exception? Problem is that Brownells will not ship that item to Canada which complicates things.

[Rancid Crabtree]

There are ways to apply more torque without distorting like the vise grip will. But being such soft material it's likely to gall and tear the threads off the housing. Also using some heat could increase the clearances but again probably not much chance of success with soft metals.
I expect the combination of electric current and moisture has corroded the threads together.

I'd try to get a replacement cap and cut the old one apart because you will likely be able to save the housing.

[Sashi]

You could try to heat the cap.

[260 Rem]

I tried some heat with wife’s hair dryer but chickened out. I am not going to get too aggressive until I hear back from Aimpoint. If there is a Canadian service spot, I will send it for “repair” after I hunt with it ... still works fine and the battery is supposed to be good for 50,000 run hours. I just would feel more confident changing to a new battery.

[JD848]

If you can get a hose clamp taped inside so you don't scratch it around your rotary switch or tape the rotary switch and tighten the clamp till it gets solid ,then you won't tear it apart while trying to unscrew the cap making it more solid so you can put out a bit more power on the top screw cap.Find some thing like a silver dollar that fits snug in your slot so you don't strip it and snap the end of the vise grip as tight as you can on the twist nut on the hose clamp,don't go crazy on the pressure and use another set of vise grips to snap onto what ever fits tight in your slot.It has to be even level pressure as you turn so you don't bust your rotary switch, I don't want you to reck your scope so this is just a thought that may work. When you tighten the clamp make sure it makes even contact 360 degrees around the rotary switch so not to bend anything.The clamp sides maybe to wide touching the cap so this may not work.Don't start cutting things until you hear from aimpoint or send it to them for the work .GOOD LUCK