Last October Americans witnessed too vividly the dangers of “bump stocks,” relatively cheap devices used to turn semi-automatic rifles into weapons nearly as automatic — and deadly — as machine guns. The devices, which helped a gunman murder 58 concert-goers in Las Vegas with startling efficiency in a matter of minutes, are an easy target for gun reform.

Perhaps the Las Vegas atrocity would usher in a saner discussion of gun reforms. Perhaps the obvious dangers semi-automatic rifles equipped with features to make them more deadly would spark reconsideration of their permissive regulation. Or perhaps at least bump stocks could be outlawed and any similar modifications would also face serious scrutiny.

Even the National Rifle Association voiced support for a review of bump stocks[1], saying in the aftermath of the Vegas shooting that “devices designed to allow semi-automatic rifles to function like fully-automatic rifles should be subject to additional regulations.” President Donald Trump has asked[2] the Justice Department to reconsider Obama-era decisions that allow them.

But so far efforts to outlaw the devices in Congress haven’t borne fruit, and now Colorado lawmakers have dropped the ball. This week Republican state senators canned a bill in committee that would have banned bump stocks[3] here.

Yes, the move is not that surprising to even casual observers of what goes on year after year under the Gold Dome. Since the successful legislative battles of 2013 that enacted reasonable reforms, including capping ammunition magazines to hold no more than 15 rounds, Republican lawmakers’ main contribution to the gun-control debate has been to stick to hardliner talking points and attempt to roll back even the modest measures passed in the wake of the Aurora theater shooting and the massacre of elementary students in Newtown, Conn.

Still, we take the moment to condemn this failure. Banning these devices would have been a real service in protecting residents. Passage of such a ban also would have sent a clear signal to national lawmakers to stop dithering.

As Boulder County Sheriff Joe Pelle put it, bump stocks “present a tremendous challenge to law enforcement.” He argued the ban should be seen as a no-brainer.

And no wonder. Bump stocks allow a shooter to use the natural recoil of the firing mechanism to speedily fire off round after round with frightening ease. A New York Times analysis[4] of the Las Vegas shooter’s fire rate found that he was able to shoot about 90 rounds in 10 seconds. A fully automatic weapon can fire nearly 100 rounds in seven seconds. Meanwhile, the rate achieved by the gunman who killed 49 in an Orlando nightclub with a standard semi-automatic rifle was about 24 shots in nine seconds.

Opponents to the Colorado ban mostly stuck to arguments based on Second Amendment freedoms, but there was also the claim that some gun owners with disabilities need bump stocks for ease of use.

Read more from our friends at the NRA