Acceptable pitch error in 16mm film perforations? What is too much?

[Lucas Xavier Simes]

Information I can find on Wikipedia suggests that the acceptable perforation pitch error in 16mm film is +/- 0.01mm.

This feels like such a miniscule number. Will variations that exceed that really jam a camera? How far can you go before a camera jams? Can I feed long pitch film into it at slow speeds without jamming it?

[Simon Wyss]

Information I can find on Wikipedia suggests

Information doesn’t suggest. What are you writing?

There are standards, ISO 69 for 16-mm. film. The permissible deviation on the hole pitch is plus minus one hundredth of a millimeter. Perforator tools are made to a tenth of that tolerance. Film is a plastic material, therefore some allowance must be made. Polyester base is dimensionally much stabler than cellulose triacetate.

Acetate film can be shrunk, hole pitch shorter by up to half a percent. Every camera should accept film that is a little shrunk but also a little swollen. Film width of 16,00 mm should run. Nominal width of strips immediately after the cut is 15,95 mm ± 0,025.

Most amateur cameras have a claw mechanism that performs a longer stroke. With a Paillard-Bolex-H it’s 7,9 mm. Professional cameras show various approaches such as a creeping-up claw, e. g. Eclair 16, or an adjustable distance between transport claw and register pin. The claw tips are tapered.

A jam most often begins by badly shrunken film climbing on a sprocket roller. If you want to avoid a jam, use polyester-base film. Contrary to the widely persisting belief there are way more jams with acetate film than with polyester. I check every camera that I service with polyester-base stock. It works always.

One film manufacturer is currently struggling to get 16 perforation right.

[Dom Jaeger]

12 hours ago, Lucas Xavier Simes said:

Information I can find on Wikipedia suggests that the acceptable perforation pitch error in 16mm film is +/- 0.01mm.

This feels like such a miniscule number. Will variations that exceed that really jam a camera? How far can you go before a camera jams? Can I feed long pitch film into it at slow speeds without jamming it?

The error tolerance you’re describing is in the manufacture, and would only affect the film stability. In other words, you need accurate perf pitch so that the recorded moving image appears stable, and without jitter. It has nothing to do with causing film jams within a camera.
There is plenty more variation than 0.01mm in film shrinkage and in the days when Fuji made MP stock there was a noticeable difference in pitch compared to Kodak that often caused noise problems in 35mm professional cameras. Many cameras with registration pins have pitch adjustment for this reason. The important thing is that the pitch stays constant through the roll, even if there is some variation between rolls. 
To cause a jam would require quite a lot more variation, and would depend on the camera. As Simon mentioned, most cameras have claw strokes that well overshoot the pitch, and registration pins are usually tapered to allow for some variation as they enter the perf.

[Mark Dunn]

I think you may be conflating pitch tolerance with the difference between camera stock, usually short pitch, and print stock ,long pitch.

The difference was to allow better alignment when making contact prints. The print stock was run on the outside of the printer sprocket with the camera stock on the inside, hence it  moved in a curve with a slightly larger radius. So it required a longer perf pitch to maintain close contact.

[Simon Wyss]

Short pitch perforation is still in use with negative stocks. Reversal stocks are perforated full pitch because they’re not intended for printing. The difference is two per mill.