One of a long list of cartridges improved by Parker Otto (P. O.) Ackley, chiefly through the 1950s, the 30-30 Ackley Improved offers a significant performance advantage over the parent case because it shortens the neck significantly, without compromising bullet pull. This is possible because the 30-30 case headspaces on the rim and it has an unnecessarily long neck. The resulting increase in usable capacity is significant. Other examples of AI chamberings that benefit similarly include the 375 H&H, 300 H&H, 30-40 Krag, 25-35, 22-250, and 250 Savage. Ackley’s design was genius. He reduced case body taper to about 0.001-inch per 0.1-inch length, which works perfectly. In the lever-action rifles in which the 30-30 was usually chambered, pressure is low enough that extraction is never an issue. However, some of the loads Ackley advocated in his 30-30 AI generated pressure far exceeding SAAMI pressure specifications; see below to understand why this is dangerous. Regardless of that, the AI design is just about perfect and harder for gunsmiths to screw up when applied to chambers for rimmed cases but they can get it done! Generally, AI designs are superior in all ways when chambered correctly. However, I must add one note of caution, Ackley and others of the era were dangerously lax when it came to respecting the value of proof-testing. Many of the recommended loads of that era generated pressure exceeding Proof-Load-Pressure. Many years ago, one of the bullet makers was sued when a customer used its data to load for the 257 AI using a propellant that generated phenomenal ballistics. Unfortunately, the published load also generated pressure exceeding normal proof-loads for the 257 Roberts or any other commercial chambering. This was common practice for the era. Just plain bad luck caught up with that Company and the unfortunate shooter. The gun failed and the shooter was killed. There was no arguing the matter, the load was patently unsafe because it entirely circumvented any value of proof-testing with normal Industry-Proof-Loads. The result was inevitable. Any one of tens of thousands of handloaders could have been that unlucky guy. Any one of the many companies publishing similarly derived data could have been the unlucky one. As it was, the company involved was sued for $5,000,000 and ruined. It had to sell out and therefore lost control over a lifetime of investment. It never has entirely recovered. Refer to the 22-250 discussion for another example of what the habitual use of loads exceeding the pressure for which a gun has been proof-tested can lead to. As with all cartridges used in guns with a tubular magazine, a properly applied crimp can smooth and ease chambering and a crimp is critical to lock the case mouth into the cannelure and thereby prevent recoil and chambering forces from driving the bullet into the case. In some instances, a roll crimp might be the best option But the Lee Factory Crimp Die usually does a better job and the crimp it applies will not damage a cast bullet as chamber pressure drives that from the case. Heritage of this case dates to 1879 with the introduction of the 38-50 Ballard case.