There are any number of gunsmiths who will remind you that when you remove the revolver’s hammer spur you also reduce the hammer’s overall mass. And when you reduce the hammer’s mass you reduce the total striking force produced when the hammer falls. This they warn us can lead to unreliable primer ignition. There are many other gunsmiths who will assure you that a properly removed hammer spur does not reduce primer ignition reliability. They argue that a slight reduction in the hammer mass will actually produce an increase in the hammer’s striking force. Their argument is that the hammer’s reduced weight leads to an increased in its falling (lock-up) speed. They go on to suggest that this increased velocity produces a squared increase in the final kinetic energy number. (i.e. Kinetic Energy equals the sum of Mass times Velocity squared divided by two.) Finally there is a third group of gunsmiths that will tell you that the bobbed hammer reliability issue is dependent on the weapon being discussed. The general rule with this third group of gunsmiths is that Smith & Wesson J- and K-frame sized guns and Ruger guns can be reliably de-horned without a reduction in ignition reliability. But they warn Colt revolvers are susceptible to ignition trouble if the work is done poorly. This is because Colt parts have a much more interdependent internal clockwork relationship with each other. Change something on one Colt part and you may adversely affect any number of other Colt parts functions including reducing ignition reliability. Now based solely on my personal exposure to a large number of bobbed hammer snubs I have to side with the middle-of-the-road gunsmiths. I have seen the work of third rate gunsmiths who have bobbed the hammers on J- and K-frame Smith & Wesson and the snubs are utterly reliable with every brand of ammunition. I also know of work performed by otherwise first class gunsmiths who removed the hammer spurs on Colts. Occasionally their work produces weapons with notable ammunition ignition issues. In the interest of fairness this situation may be exasperated by the very limited number skilled Colt gunsmith compared to the otherwise larger number of Smith & Wesson skilled gunsmiths. Because good Colt gunsmiths are so hard to find too many Colts end up in the hands of gunsmiths who lack the experience to properly attend to the work. Personally I am not concerned with ignition issues from any of my de-horned self-defense snubs. But I also only turn to master level gunsmiths for such work. I also test all my modified snubs with a wide variety of ammunition many featuring the hardest primers I can locate. Any shooter who desires a bobbed, hammerless or spurless hammer but is hesitant due to reliability concerns is encouraged to research his area gunsmiths before buying the service. If additional reassurances are required consider having a heavier spring installed to increase the striking force of the hammer. This is a belt-and-suspenders approach to ignition reliability but in a self-defense weapon it is a comforting one. Conducting a through ignition test following hammer spur de-horning is also always advised. One final note, in years past Smith & Wesson and Ruger to name only two offered factory produced bobbed hammers as after-market parts. Maybe these companies or a dedicated aftermarket manufacture can be imposed upon to reintroduce these parts again.