How to remove this Bolt?

So I encountered what I'm pretty sure are either 8mm or 5/16" versions of the bolt pictured below.  Typically I've spun and then hurley'd larger versions of these out with relative ease, but there's a bit of a wrinkle in that the installer looks like they used some sort of adhesive (I'm guessing epoxy) between the outside of the sleeve and the inside of the hole.  That factor, plus the narrower diameter has me concerned that it'll just snap off in the hole (and leave the sleeve) if I apply any real amount of force to it in tension.  (even if I could find the right size adapter, spinning it won't do any good unless I can figure out how to break the bond created by the adhesive between the sleeve and rock)

Thoughts?  Core drilling is the best I can come up with, but I'd love to hear it if there are other ideas.

It's not mission critical that we go hole for hole, but it would obviously be preferred.  That brings up the next question: if I can't go hole for hole, what's the most elegant way to chop and patch these things?  Hammering them in and then patching is iffy as the sleeve looks like it'll still protrude a couple of mm out of the hole making it hard to patch well.  I've had mixed results trying to bash sleeves like that in with a punch.  Often it doesn't go very well as the surrounding rock is so soft that it chips out at a rate similar to or faster than the rate that the rolled metal deforms into the hole...

Red Head Dynabolt. (Cheap-ass driller had a <$1/bolt budget, I guess)

This article is for masonry applications: the author suggests you can disengage the wedge, then use a plastic wall anchor in the space between the sleeve and the concrete (or rock). That doesn't sound do-able to me, but might be an avenue to explore. Drilling a tiny shallow hole next to the bolt in order to insert a screw that will hopefully bite the sleeve more than the rock? Similar to removing a Triplex, but without the help of a flange. The glue does add to the difficulty tho, and the rust and the weak steel don't help.   

https://hipages.com.au/article/how_to_remove_a_dynabolt_or_sleeve_anchor 

BITD it was popular to put silicone chalking inside the holes. The thinking was that is kept the water out. Yeah that didn't work out great, in fact it made them rust faster. 

If it's glued in and you're installing glue-ins you can just drill a hole directly above the old stud. HowNot2 did a video on that a while back.

If you’re talking about the ones with a 5/16” threaded core and a 3/8” sleeve, you’d normally hope to have a few mm of the sleeve sticking out of the wall. There’s more info here in the forums referring to them as lok-bolts (Redhead sleeve anchors). Typically you tap the core in, pinch the sleeve and core together with Vice grips, and wiggle it out of the hole, but I’m sure having glue present makes this quite a bit harder. I haven’t dealt with that combo.

Unless the Vice grips wiggling works, I’ll be a bit surprised if there’s a way to remove those at all. Maybe you could use a 5/16” to 3/8” coupler nut and a short piece of 3/8” thread to adapt a 3/8” spinner tool to that bolt? Spin, then use the adapter to connect to a Hurley Jr? I’ve done something similar with 1/2” wedge bolts. Good luck!

Find the one who installed them and make them drill them out while you watch with crossed arms and a big frown.

Probably would go straight to chop and patch on this if hole for hole is not mandatory. I would cut the stud as close as possible without scarring the rock, drive it back as far as you can, then fold the sleeve into the void in the center to keep it from mushrooming out as it would if you tried to hammer it straight in. If you are patching tuff the copper and grey instacrete mixed to match the tone of the rock in that location has worked nicely for me in the past.

If you are going up to a 5/8" hole and really want to reuse the location, "redneck core drilling" (tiny holes around the sleeve with a really skinny sds bit) may be an option to not have to core drill/water cool for removal, but depending on the amount and quality of the epoxy likely will be just wasted time...

For chop/patch of adhesive anchors in general I have found that using a grinder with a small wheel helps to let you slightly recess the remaining stud so you can patch flush.

Drew Nevius wrote:

There’s more info here in the forums referring to them as lok-bolts (Redhead sleeve anchors). Typically you tap the core in, pinch the sleeve and core together with Vice grips, and wiggle it out of the hole, but I’m sure having glue present makes this quite a bit harder. I haven’t dealt with that combo.

This is what I've done. You can also tap around the sides of the bolt (maybe with the hammer pick or chisel) to "unstick" a heavily corroded anchor, or in this case, glue to make it easier to pull with the vice grips. If you can get a good grip on the sleeve, and it is loose, the anchor ought to come right out. Easiest bolts in the world to remove without an adhesive holding them in. 

Never heard of anyone filling a hole with silicone... People where still "sealing" the edge of the hole when I started placing bolts -- after they were already hammered in. Most of us that were taught that figured out how stupid it was and quit doing it.