Factual error: Dutch police cars don't look like they do in the movie, with their blue and white checkerboard pattern. They had blue and orange diagonal stripes on the side. In this movie, they look much closer to what British police cars look like.
Factual error: Twice in the movie a Jumbo Jet (a Boeing 747) from Pan Am appears. The movie is set in 1969, when that plane had its maiden journey, but it wasn't flown commercially until 1970.
Factual error: When Dracula is about to bite the neck of his female assistant you can plainly see him in her vanity mirror and as all good horror fans know, you can't see a vampire in a mirror, especially Dracula.
Factual error: That is not a crocodile that attacks Sue. It more closely resembles an American alligator - the squat, rounded snout gives it away. Australian crocodiles have a much sharper, more angular snout. There are other tell-tale physical features, most notably the placement of the alligator's teeth when it closes its mouth, but that's the main one.
Factual error: The story is set in 1976. "Funkytown" is used in the movie and the end titles. The song was not released until 1980.
Factual error: The movie takes place during the 1990s, but throughout the movie cars are shown with Illinois license plates with "Illinois" written in cursive. These plates were not introduced until 2001. (00:24:45)
Factual error: In the movie, we see the Statue of Liberty with its current bluish-green color. The statue only got that color over time, and as it was still being built, it should be its original brown.
Factual error: When the B-52 is flying low over Russia, the shadow on the ground is a Boeing B-17G, a World War II propeller driven bomber.
Factual error: When the barracks are completely flooded, Eggsy uses his bare fist to punch through a large two-way mirror to escape. The fact is that any glass (or plexiglas) thick enough to contain hundreds (or thousands) of tons of water without bursting would be as impenetrable as concrete to Eggsy's bare fist. He would need a chisel-tipped jackhammer to penetrate such a mirror.
Factual error: The terrorist with the AK47 is unaware of the fact that a Harrier is hovering just outside the window until he slowly turns and see it there. He does a double take when he sees the Harrier just five metres away! A Harrier is an incredibly loud aircraft; you can hear them from three kilometers away. At that range the floor would shake with the noise and he would have been in no doubt whatever that he had been under attack for some time.
Factual error: In the montage sequence showing Drew Barrymore hanging out with the math club, they have a Pi poster with 3.1457869986. Only the first 3 digits are actually correct. (Pi = 3.1415926535897...) (00:25:20)
Factual error: Dexter the capuchin is in the African mammal display. Capuchins come from South America.
Factual error: When it's 00:00 on January 1st, it's not night in Sydney, it's 11 AM. When they 'reveal' stuff at the end of the movie, and they show that things happen exactly at 00:00 in the night in London, it can't possibly be dark in Sydney, Australia.
Suggested correction: It shows that Sydney is at dusk and is becoming dark, so around 5pm-6pm-ish, not 11am during the day.
Factual error: It is stated that Miss Trunchbull competed in the Olympics in shot put, javelin, and hammer throw. According to her jersey those were the 1972 Olympics. The hammer throw wasn't added as an Olympic event for women until 2000.
Factual error: They are present at Frankfurt, Germany. But with a closer look you see a cathedral at the right side. This cathedral and the central station are located in Cologne, Germany - they are about 220 km apart. (01:04:15)
Factual error: During Jack's sliding down the rope scene, it is very noticeable that each one of the English soldiers fire their weapons more than once, which is impossible for that time, knowing that repetition weapons weren't invented until the mid 1800s. (00:20:00)
Suggested correction: The first repeating firearm was invented in 1718.
I think you are talking about the Puckle gun from 1718, which was a crewed gun, not a rifle. The earliest repeating rifle is from 1630, with more variants made till the era the movie takes place in (early 18th century). However, these had all what you call single-action triggers (manual repeating), meaning they need a large lever to reload after firing. The guns in the movie obviously don't have such a lever. What the poster probably meant by repetition weapons is double-action trigger rifles.
Factual error: Opening scene shows NYC 1962 as a 1964 Chevy Impala rolls by.
Factual error: All the Cisco VoIP phones seen in the film have the booting Cisco logo on them and would not work due to no connection.
Factual error: The movie is set around 1995. But the SWAT team in the movie is wearing gear from the 2000s. (MICH-2000 helmet, modular tactical vest, M4 variant with picatinny rails and scope). Plus, in a scene when the guys are shopping for a taser (gun shop scene), some of the rifles on display are from 2000s era. AR-15 variants with variant stock, foregrip and picatinny rail. Those style of weapon system were unheard of in early 90s. Even Special Forces just adopted it by the late 90s.
Factual error: The picture of Eddie and Teddy on the road with dad, supposedly taken in 1906, shows a Ringling Bros and Barnum & Bailey circus poster. In 1906, the Ringling Brothers circus and the Barnum & Bailey circus were two separate circuses playing in different parts of the country. They did not combine the two shows until 1919. (00:27:00)
Suggested correction: You can tell by the shape of the snout and the ridges above the eyes that, although animatronic, it is meant to be a Marine Crocodile that is native to Australia. It doesn't resemble an American alligator, which doesn't possess those pronounced ridges. Also, freshwater crocodiles can be seen in the boat ride scene where Mick motions for Sue to lean up off the edge of the boat. They have the narrower, angular snout that you referenced.
The placement of the alligator's teeth when it closes its mouth shows that it is more like an alligator than a crocodile. In fact, the animatronic puppet is a bizarre mish-mash of physical characteristics of both crocodiles and alligators.