Notable in the production is that the main actors all have the same character names in every movie; James Ellison is Shamrock, Russell Hayden is Lucky, Julie Adams is Ann, and well-known character actors Raymond Hatton and Fuzzy Knight play the Colonel and Deacon, respectively; and this is despite Hatton and Knight playing both good guys and villains, actual Colonels or nicknames, actual Deacons or a person named Deacon. I suppose if you shoot six movies at once it's hard enough to keep everything straight without having a different name in every movie.
The same supporting cast mixes it up and plays different parts in each movie, bad guys and deputies and barbers and bartenders. Notable among them is former silent star Tom Tyler, at the end of his career and generally playing the villain's right-hand man.
Apparently they shot all the scenes for each movie at each location--be it a ranch, a saloon, the western town streets, and so on--at one time, and moved on. Some stock footage--notably of a runaway stagecoach--is repeated also. Of course, when these movies were made there was no notion that they could or would be watched back to back on DVD, so these elements would never be noticed by moviegoers, and was a pretty clever idea by director Thomas Mann. They are all also apparently rewrites of other b-movies from decades past.
And the movies, perhaps in spite of or because of their shortcomings (and short running times), are pretty enjoyable. My favorite is COLORADO RANGER, where the Shamrock Kid, Lucky, and the Colonel are rogues hired to run off some homesteaders; they take a shine to Ann instead and switch sides. This one shows an easy camaraderie as the trio cheat at cards, practice trick shooting, and end up having to take care of a baby--who they pacify by letting him play with a gun.
CROOKED RIVER changes it up as Lucky leads a gang of bad guys against Shamrock, but has a change of heart when one of his henchmen (John Cason, who has memorably bad guy turns in several of these ) blinds Lucky to make off with Lucky's kid sister Ann. Lucky was getting tired of the outlaw life anyway and jumps back over to the right side for a memorable finale.
FAST ON THE DRAW starts with one of those repeated stagecoach scenes, and Shamrock's parents are killed by outlaws, with little Shamrock the only survivor. He develops a phobia against guns, which is unfortunate when his motor-mouthed sidekick Lucky brags them up to the point that they are made lawmen in a town terrorized by an outlaw called The Cat. Fortunately Shamrock gets over his childhood fears in time to deal with The Cat.
In MARSHAL OF HELDORADO Lucky takes what he thinks is a sweet job as sheriff in a town without realizing the short life expectancies of the former lawmen. The town is terrorized by the Tulliver Brothers (with good scenes from all the usual supporting cast), and Lucky's only help is Shamrock, who plays a guileless Eastern dude (who rides into town on a mule!). Naturally Shamrock has a few tricks up his sleeve after all--including inducing two of the outlaws to shoot each other--and the good guys win in the end.
WEST OF THE BRAZOS is a knotty yarn for a b-western as The Cyclone Kid (John Cason, good again, and Tom Tyler gets a bigger villainous part too) pretends to be Shamrock to claim jump on his family ranch. But Shamrock is on his way home after many years away. He crosses paths with a wounded marshal, who convinces Shamrock to impersonate him to capture The Cyclone Kid. Shamrock ends up in jail for impersonating a police officer, and fake Shamrock seems triumphant, but Lucky saves the day with a neat trick. Lucky has an interesting role in this one; he was deafened during the war and has learned to read lips, and a couple of memorable scenes make it look like he has nerves of steel because he can't hear people shooting at him.
HOSTILE COUNTRY is probably the least of them, as Shamrock goes back home after his mother's death (again) to meet a stepfather he doesn't know (also part of WEST OF THE BRAZOS) and finds his stepfather making enemies of everyone around, including Shamrock and Lucky. As in most of these, everybody isn't quite who they say they are and some fistfights and gunplay is required to sort it all out.
These have been nicely collected in a two DVD set called The Big Iron Collection, and is worth checking out and thinking about.