Gun safes, concrete, and AnkaScrews

tl;dr Would eight 10mm x 60mm AnkaScrews into concrete be sufficient for a 3-gun safe?

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Standard question from a newbie. I've read the FSA guide (but not the legislation)
https://www.firearmssafetyauthority....e-guidance.pdf

I'm securing a small 1.45m high 3-gun safe to the concrete foundations in the under-garage (side and back). The concrete is absolutely solid. I've no building plans (old house), so am not sure where the damp-proof course is (or anything else I might not want to hit). There is rebar.

I'll also likely be replacing the safe with a bigger 6mm one later, and would like to be easily able to remove/hide the fittings and make good.

The safe comes with 6 expansion bolts (4 base, 2 back) 70mm deep, 7mm wide. So they comply with the basic regs, but I'd rather not use expansion bolts as they'll make a huge mess when I remove them later.

I quite liked the idea of lots of inset drop-in anchors that I could then just fill over when I change the safe, but they tend to only have 20-25mm engagement with the thread. No matter how good they are in practice, I imagine many inspectors will fail them because of the 50mm engagement guidance.

I'd like to use Ramset 10 x 60mm AnkaScrews (galvanised), as they're easy and clean to remove (if you have access to the inside of the case). 54mm of thread, so that should be enough, and reduces the risk of hitting rebar/damp membrane. 4 in the base, and I'll drill a couple of extra holes in the case and put 4 in the back.

Pass? Fail? I've seen someone who knows what he's talking about from a building/engineering point of view recommend them on this forum, but not whether the inspector is likely to approve.

Would be OK. But just drill over deep holes for expansive anchors and later you can hammer them down below surface level and cover the holes easily

You can buy glue now that would take the conc off if you tried to remove the safe. I hate drilling holes into conc floors, had to fix a broken damp course

One of the risks of drilling into the concrete is hitting a spot where for whatever reason the slab is thinner than it is meant to be and you punch right through. I had that happen when fitting the anchor bolt for the bottom stud of one of the partition walls I put in my basement - was supposed to be a 100mm+ slab but drilled in 70mm thereabouts for an anchor bolt with 65mm penetration needed and popped through and found clay as I was getting to the marked depth. Hmmm...

What you can do is use a high quality permanent and fully underwater rated sealant (not roof and gutter silicon) and plug the hole with that until it's full, then fit the anchor bolt. It's not the "approved" repair for a breach in the damp proof course, but from my experience of it and if you use the right product with a cleaned up hole to remove any dust etc, it is as effective as not holing through and the DPC wasn't damaged.

For the anchor bolts, the Ankascrews would work I think as they have a similar rating to the wedge anchors, but I don't see any reason not to use anchors. You can drill the hole deeper than needed, and at removing time pull the wedge bolt up, cut it off, and punch it deep down as someone else suggested. If you get the type where the wedge sleeve is one piece and not two (some makers have a wedge section that is the same for all their sizes of anchors and then a different length sleeve for the various lengths of bolt to take up the extra space), you can sometimes punch the bolt down and lift the wedge sleeve out of the hole and then recover the bolt with a magnet as well.

Ankascrews perform far better that Dyna bolts etc as the diameter is bigger of the steel doing the biting to the concrete. Example a 10mm Ankascrw is 10mm diameter + the threads, a 10mm Dynabolt is only 8mm internal bolt likewise a 12mm Dynabolt is only 10mm.

The kN in both shear and tension are higher in Ankascres than Dynabolts. Trubolts are similar in performance to Ankascrews however you are left with a protruding thread where as the Ankascrews leave only a hole.

Bottle brush the dust out of the holes vigorously
Some malphoid/dpm/tarpaper in a layer under the floor of the safe will separate the steel from the damp concrete, smearing it with grease would also help

With anka screws I find that you can nip them up and the max torque arrives quite quickly, too much and they just spin

If they won't rattle in they often take dust off the internal faces so rattle them back out, blow out the hole and try again

If you go dynabolts you can undo them later, pin punch the shaft down into the hole and fill em back up same as an ankascrew hole

Ankascrews will be fine, and for a non-endorsed small safe I'd probably only use one in the bottom and a couple of coach screws into the wall. Even for a 6mm endorsed 10 gun safe I'd probably only use a couple into the floor and a couple of wall fixings - the vetters seem quite happy at that.

i got vetted a week back, he was more than happy that my safe was dynabolted and screwed. he also commented my security setup was over the top but that it was a good thing.

Ankascrews is what I used, the inspector tried tugging on the safe, looked at the heads and passed it.