On Tue, 04 May 2021 17:58:20 -0400, Radey Shouman
wrote:

An 18" bolt cutter will go through a 5/16" Master lock shackle in a
second or less. Long ago I went through dozens at work (keys had
been lost).

You might have some difficulty cutting through the Master Lock Boron
shackle. I also have an 18" bolt cutter (that I carry in my car). I
have little difficult with the smaller shackles, but can't cut a
shielded shackle or the hexagonal boron steel shackles.

However, you bolt cutters are obsolete. What you (and I) need are
hydraulic bolt cutters.

https://www.ebay.com/sch/i.html?_nkw=hydraulic+cutter

"[765] How Tough are Master Lock’s Boron Carbide Shackles?"
https://www.youtube.com/watch?v=ICudP7-FxVw

"[789] Hydraulic Cutter vs. Bell’s 16mm Shackle Bicycle U-Lock
(Catalytic 750)"
https://www.youtube.com/watch?v=-nPY7cLu0S4

Hint: Do NOT ride your bicycle through town with a pair of 18" bolt
cutters tied to the rear rack. The police have the irritating habit
of asking far too many questions about the bolt cutters.

--
Jeff Liebermann
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558