What Size Gun Safe Do I Need (Halve the Gun Count, Then Measure)

Gun safe size chart by what you store

Gun safe size follows what you store: handguns only need a 1-5 gun vault, while a growing long-gun collection needs a 55-72 in tall safe rated for twice its count. The size classes below follow our reading of the Sportsman’s Warehouse gun safe size chart, with the rated capacity I would shop for each situation.

Weight climbs fast with size, and our guide to how much a gun safe weighs shows the spread by class. The rated capacity column applies the halving explained next; its upper end leaves room to grow.

Why gun safe capacity ratings run high

Gun safe capacity ratings count rifle rack slots filled with bare rifles, so real capacity is about 50-65% of the number on the box. Liberty Safe says its gun count is the number of slots in the racks, and that scopes, AR-15s and accessories reduce how many guns fit. Rhino Metals says a scope roughly doubles the space a rifle takes.

We see this as the most common complaint in owner threads. On The High Road, one owner’s rule is to “always take the max number of long guns they say the safe will hold and cut it by at least 1/3.” I use Rhino’s 0.5-0.65 range to turn a rating into a real count:

Handguns on shelving or a door organizer, ammunition and documents come out of the same space, which is why the safe feels full on day one.

How to choose gun safe size in 5 steps

To choose a gun safe size, start from your longest gun and your real gun count, not the rating.

1. List every gun and mark which have scopes, pistol grips or long magazine tubes.
2. Measure your longest gun from muzzle to butt; that length sets the interior height.
3. Double your long-gun count to find the rated capacity that fits today; double it again if you are still buying (Rhino’s rule: 10 long guns, buy for 40).
4. Add shelving or a door organizer for handguns, ammunition, cash and papers.
5. Measure the spot, the doorway route and the floor, then compare them with the maker’s exterior dimensions and minimum doorway.

A safe stays where it is for years, so step 3 is where I think most buyers save the cost of a second safe.

Gun safe interior height for scoped rifles

A gun safe for full-length rifles needs about 56-58 in of interior height. A bolt-action rifle with a 30 in barrel is about 52 in long, and Tractor Supply suggests 58 in inside so a top shelf still fits above the rack.

I always check the interior figure, not the outside. Liberty’s Centurion 24 stands 59.5 in tall outside but offers 56 in of interior height, which clears that 52 in rifle with about 4 in to spare and no shelf over it. The Tractor Supply video in this section starts with the same step: measure interior height against your longest gun.

From our notes: Liberty’s Centurion 24 and Centurion 32 share the same 56-inch interior height and 26.25-inch width. The bigger rating buys 4.5 inches of extra depth, not taller room for long barrels. I now read the interior height line first and the gun count last, because a higher number on the box can still leave a scoped rifle with a long barrel brushing the ceiling.

Gun safe size vs your doorway, stairs and floor

The largest gun safe you can use is the largest one that fits through your narrowest door and sits on a floor that can carry it. Liberty lists a minimum doorway for each model: 18 in for the Centurion 12 and 25.75 in for the Centurion 32. Liberty also says to add about 0.25 in of depth for the outlet kit, 1.5 in for a plug and 1.75-3 in for the handle.

In my view, floors matter as much as doors. Sportsman’s Warehouse puts most residential wood floors at 40-50 pounds per square foot and suggests placing a heavy safe near a load-bearing wall. The Safe Keeper adds that upstairs it should sit over floor joists, not in an unsupported mid-span. A bigger safe also means a harder move: on the Smith & Wesson Forum one owner warns, “There are no small mistakes when moving a 1,000+ lb safe.” Our guide on how to move a gun safe covers stairs and when to hire a crew.

Gun safe size for renters and small apartments

Renters do best with a tall 12-18-gun-class safe of about 245-336 lb, which still fits long guns and comes back down the stairs at move-out. Those weights are Liberty’s figures for the Centurion 12 and 18. On Texas Gun Talk, one poster wrote that “A 300-400 lb safe will hold what he needs and can be lag bolted to the wall/floor.”

A small safe is also easier to carry off, so plan to bolt down the safe wherever your lease allows. One owner on The High Road keeps his safe bolted to the floor and tucked into a corner. My picks for the best gun safe for an apartment cover light models and no-drill options. Firearm storage rules differ by state and city, so read the official guidance from your state attorney general or state police before you choose where the safe goes.

How fire insulation shrinks a gun safe’s interior

Fire insulation adds wall thickness, so a fire-rated gun safe is bigger outside than its interior suggests. Liberty’s Centurion 24 measures 59.5 x 28.25 x 20 in outside and 56 x 26.25 x 13.5 in inside. That is 3.5 in of height, 2 in of width and 6.5 in of depth taken by steel, the door and insulation.

Its 40-minute fire rating at 1200°F is Liberty’s own claim; the page names no outside lab. We treat a longer rating as a sign of thicker walls, so compare interior dimensions for your guns, exterior dimensions for your room, and look for who certified the rating, such as UL or Intertek/ETL.

Which gun safe size should you get?

The right gun safe size is the smallest one whose real capacity, at about half the rating, still holds today’s guns plus the ones you plan to buy.

• Handguns only: I’d pick an extra-small handgun safe for 1-5 pistols.
• Renter with 2-5 long guns: a tall 12-18-gun-class safe light enough to move.
• 6-10 scoped rifles: a 20-40-gun-class safe with at least 56 in inside.
• 15 or more long guns plus valuables: a large 40-64-gun-class safe on a ground floor or slab.

If you already know your count, my best 24 gun safe roundup compares real rifle capacity on five models. Once the safe is in, a gun safe dehumidifier sized to its cubic feet keeps the guns dry.