An Afterthought

I have been discussing yesterday’s pattern testing results with a friend and one of the first questions he asked me during that discussion was whether I would have to go down the road of reloading .410 to tune a cartridge to my requirements. It’s certainly a tempting possibility, as I tend to find reloading enjoyable in it’s own right, strange as that may sound.

I went on to say that my thinking on what ought to make the best-performing .410 cartridge hasn’t deviated very far from where it started back before the Yildiz arrived: something like 16-18g of #7 shot propelled at moderate velocity by a full-length plastic wad.

Rather gratifyingly, most of the tests I’ve done so far have acted as confirmatory data points around that particular idea rather than contradicting it, so the question becomes not what to choose, but whether or not there is a commercially-available cartridge that fits that specification. Most of those I’ve tested so far have one component wrong – perhaps the velocity is too high, or the shot size too large, or a rolled turnover and card have been used instead of a crimp, etc.

On the basis of the data and experience in the field, the Eley Trap load is the best choice so far, but I’ve wounded several birds at longer range with it and I’d prefer not to have to rely on #7½ to get sufficient pattern density unless I have to.

The subsonic tests yesterday did clearly show the advantage of dropping the muzzle velocity. 74% pattern density at 30 yards is – percentage-wise – way above anything else I’ve seen previously and especially impressive given that the cartridge is loaded with a fibre wad. That the performance was better at 40 yards too is equally pleasing. However, the price one pays for that performance is a substantially lower per-pellet kinetic energy (remember that the relationship between velocity and energy is quadratic, not linear). Let’s say a cartridge loaded with #7 gave similar performance (and I doubt it would, for various reasons): you’d get the pellet count required for 40 yards, but probably not the impact energy because you’re starting off 300-400fps slower than a normal supersonic load. Subsonic #6 are, on that measurement, a much safer bet, I’d think.

So reloading may come into it. If I could get hold of some very hard shot (5%+ Sb), in size #6½ with little variation between individual pellets, and put 17-18g of it atop a plastic wad and a slow powder giving 1050-1080fps at the muzzle with smooth acceleration, I might just have the perfect .410 load. But that’s really not so far from some of what’s already available, and whether the difference between that and the next best cartridge would actually be quantifiable… well, I’m sceptical.

On one level, it’s just easier to stick an ounce-and-a-quarter down a 12 gauge and forget about all these minutiae!

Ultimately, more testing is required. I’ve still got the two Fiocchi loads to test and the major deficiency in the data (i.e. that I’m only shooting 2 patterns per combination at the moment) needs to be corrected. I need to go back and shoot 5-6 more patterns – at least – with each cartridge and choke, to improve the reliability of the conclusions I’m drawing from what I’m seeing.

I also have one long-term question which I still want to answer, which is exactly how close in performance terms the 2½” and 3″ loads are. We know more lead makes for better killing patterns, but I remain interested in testing some of the 2½” shells to see if the percentage performance is better with a shorter shot column. Perhaps after I find the best-performing of the 3″ cartridges, I’ll have time to look into it.