I have a decoy RSC that I keep some low-value items in to hopefully take the brunt of an attack if a thief wants to try his hand at opening a safe... to keep them busy and not focused on where the real valuables lie... that being said, it still contains things of some value, that I occasionally use and I don't want openly accessible etc.

Anyways, the digital lock failed (it's a cheap one) and the backup key was misplaced in a move... and I needed something out of that safe for a Women's Range Day I was hosting at my private range...

I had 1-1/2 hrs before start time of the range day... I pulled it off in 20 minutes.

Had I not cared about completely destroying the RSC I could've done it in less than half the time. But I cared about the items in the safe at least a little bit and I wanted to maintain the integrity of the safe making for an easy repair. I also didn't want to make a massive mess so I was holding a shop-vac hose between my legs to catch most of the metal shavings and gypsum dust.

I removed the digital lock, used a hole-saw to drill an access hole. Then, like an amateur (even though I knew better), I tried drilling the mount-studs for the key lock and then punching it out. I likely did irreparable damage to the key lock (haven't had time to inspect that one yet). That failed so I went to a different approach. I could see where the bolt-mechanism reinforcements were welded onto the inner steel layer of the door, I simply drilled the welds from the back side then I hit the "bolt actuating arm" with a hammer and punch to bend it out of engagement with the lock mechanism. Door handle opened just as smoothly as if I had unlocked it the proper way. To fix I just have to re-weld those welds and spot back in some sheet metal to cover the hole; the digital lock will completely mask the area I attacked. As a matter of fact, with the digital lock put back on the safe there is ZERO visual sign the safe was attacked, not even from the inside. Had it been a smart criminal that did it instead of myself it may have taken me a LONG time to notice it had been compromised.

What gauge of steel?

What type of drill / hole saw?

I'm not sure gauge...it's a "no-name" I got on a blowout sale for less than $400. It's maybe 1/8" ... but really, even 1/4" can be drilled with a holesaw, just add a couple more minutes...

Drill: 18v Dewalt Cordless, didn't even use up a full battery
Holesaw: Porter Cable regular bi-metal holesaw that can be bought for $5

If you don't care about the condition of the safe (or many of the contents) I would bet damn near any RSC or "safe" could be entered quickly. Home tools work, but a gas cut off saw, angle grinder with a few discs, sawz-all, etc can all make short work of most of the things people buy to keep guns safe. that's why I think the layered approach is where it's at. hard to get in the house, hard to find the good stuff, tools not nearby, neighbors, cameras, etc.

I realized while safe shopping I had enough stuff in my garage to get into anything I could reasonably afford

Yes!  Don't pre-install safe cracking tools in your house or garage.  I keep the batteries to my drills and saws in the safe, along with the crow bars, axes, etc.

You either: #1 Don't have enough guns, #2 Don't have enough tools, or #3 Took the "buy more than you need" approach overboard if you can fit all your guns AND tools that could be used to crack a safe in the safe...

Even some decent safes are not 1/8" thick. My Browning is 10 gauge body and feels solid, that should be 0.14". Most cheap safes are 14 gauge or 12 gauge on ~$800 models. They will deflect when you hit them with your palm.

I have a cheap Stack On safe that had a rifle box fall and block the transfer bar keeping me from unlocking it. I keep trying to find another way in but when I drilled the back of it to attach to the studs it was a joke. All I probably have to do is drill a small hole so I can push back the box but I keep hoping the jiggle method will work out.