By Kent · Lock Depot Staff Writer

The door already has a cylindrical cutout. Do you re-prep it or work with it?

A school district calls about a corridor door on the science wing. The old lockset died, the hardware budget got cut twice this year, and the facilities guy wants to know if he needs a locksmith with a mortiser or just a screwdriver. That question, cylindrical or mortise, comes up on more retrofit jobs than any spec sheet admits. Sargent makes both a cylindrical lock, the 6500, and a mortise lock, the 8200, and the right call depends on what's already cut into the door, not on which one sounds tougher.

Sargent 6500: drops into an existing cylindrical prep

The Sargent 6500 is a Grade 2 cylindrical (bored) lockset. Check the cutout and backset on your door before you order. It ships less cylinder, so order a mortise cylinder separately to match the building's existing keyway, and it comes in the same function families most schools already spec: storeroom/closet (65G04), entrance/office (65G05), and classroom (65G37). Storeroom keeps the outside lever locked at all times, key-only entry, free exit from inside. Classroom is the one that trips up a substitute custodian: it locks and unlocks from outside with a key, but the inside lever is always free, so a teacher can lock the door from the hallway without a student getting trapped.

Sargent 8200: a mortise pocket, and a heavier case

The Sargent 8200 is a full mortise lock. It needs a mortise pocket cut into the door edge, not a bored hole, and if the door doesn't already have one, that's a re-prep job, not a drop-in swap. What you get for the extra work is a heavier case and a lock body that carries more of the door's structural load at the edge, which is why architects still spec mortise on new construction and on doors that see real abuse. Same function logic carries over: 8204 is storeroom/closet, 8205 is office/entry. If a facility is standardized on 8200s building-wide, matching the function code keeps the spec sheet consistent even when you're mixing mount types across a renovation.

The price gap is real and it's not close. A 6500 cylindrical runs a small fraction of what an 8200 mortise costs in the same function and finish. That's not a knock on the mortise lock. It's a mortise pocket, a heavier case, and more machining, and all of that costs money. It's the reason a tight hardware budget pushes toward cylindrical every time the door prep allows it.

Which one for the corridor door

If the door already has a cylindrical cutout, order the 6500 and move on. Re-prepping a working door for a mortise pocket to save nothing but bragging rights is a bad use of a facilities budget, and I'd tell any GC that to his face. If you're specifying new doors, or the frame is getting replaced anyway, that's when the 8200's heavier case earns its keep, especially on a door that takes real traffic. I won't spec cylindrical on a door I know is going to get slammed by a cart every day. That's a mortise door.

One thing that catches installers replacing a Schlage or Arrow cylindrical lock with a Sargent 6500: check the existing prep against the part before you order. Do not assume the hole in the door fits, especially on an older door that's been rekeyed and swapped more than once.

Stocking both on the truck

If you're a locksmith fielding calls from a district with a mixed building stock, older schools on mortise, newer additions on cylindrical, it's worth carrying both function families rather than guessing over the phone which one a given corridor needs. A quick look at the door edge on arrival tells you which one you're dealing with in about ten seconds: a bored hole means cylindrical, a rectangular pocket in the edge means mortise. Show up with the wrong lock body and it's a second trip, and nobody bills a district for a wasted drive without an argument.

Warranty backs up the price gap a little: the 6500 carries Sargent's 7-Year Limited warranty, while the 8200's cast stainless steel chassis is backed for 10 years. That's not a reason to spec mortise on a door that doesn't need it, but it's a real data point if a facilities director is weighing the extra cost against how long the lock has to last.

What we stock

We carry the 6500 storeroom function and the 6500 entrance/office function on our Sargent hub, both in Satin Chrome. If you're already committed to mortise, our piece on the 8200 function codes for a school corridor breaks it down in more depth. And if the budget calls for cylindrical everywhere, we've also written up the Sargent 10 Line, Sargent's other cylindrical family, separately.

Common questions

Can I put an 8200 mortise lock into an existing cylindrical door?

Not without re-prepping the door. A mortise lock needs a pocket cut into the door edge, which a cylindrical door doesn't have. If the door isn't already mortise-prepped, that's a new door or a shop job, not a field swap.

Does the 6500 ship with a cylinder?

No. It ships less cylinder so you can order a standard mortise cylinder in the keyway that matches the rest of the building. Match it before you order the lock, not after.

What's the difference between storeroom and classroom function?

Storeroom keeps the outside lever locked at all times, key-only. Classroom can be locked and unlocked from outside with a key, but the inside lever always stays free to exit. Classroom is the one schools want on a door a teacher needs to lock in a hurry.

Is the 8200 worth the extra cost over the 6500?

On a door that's already mortise-prepped or getting replaced, yes. On a door with a working cylindrical cutout, re-prepping for a mortise lock just to get a heavier case usually isn't worth what it costs.

Will a Sargent 6500 fit where a Schlage or Arrow cylindrical lock used to be?

Measure the existing prep before ordering, especially on an older door that's been rekeyed more than once. We do not list the 6500's prep dimensions, so give us the door details and we will check the part against them.