Today I visited several of my local RFDs in the hope of acquiring some new brands of .410 cartridge to test. Happily, I was successful and came home with four new cartridges to pattern. Although a planned brief trip out tomorrow morning will give some time for patterning work, it’s unlikely to be long enough to finish testing the Bornaghi and Eley cartridges and complete reasonable tests on all four of the new cartridges as well, so what I’ve brought home today should keep me busy for the next few weekends, if not longer.
As it happens, I’m currently in the process of designing a portable, collapsible pattern plate which will take 40″ square pieces of cardboard or paper and hold them securely for the purposes of shooting patterns. The idea behind it is to speed up the patterning process with the use of pre-cut squares of cardboard that can be slotted into a frame and to overcome the issues we had last weekend with wind and – to some extent – the driving rain. I’ll post again on this subject at some future point when a little more progress has been made.
I could post a picture of four boxes of cartridges and leave it at that until I come back with the test results, but those of you who know me will look at it and think “hang on – this chap has been banging on about not using over-sized shot in a .410 for as long as I’ve know him and now he’s gone out and bought cartridges loaded with exactly that!?” With that in mind, I thought it might be worth briefly explaining the rationale behind my decision to buy these particular brands and leave the other kinds in the shop.
But first, here’s the picture:
Lyalvale Express Supreme Game 16g / #6
My purchase of the Lyalvale cartridge is probably the most irrational of the four cartridges I’ve acquired today. On paper, it is unlikely to produce the usable 40-yard pattern I seek (presumably containing only around 150, over-large pellets to start with) and I would be extremely surprised if the reality is any different. A fibre wad is also likely to prove detrimental.
The cartridge therefore holds only one point of interest for me: it is the one of the two lightest 3″ loadings commercially available (along with the still-elusive Gamebore 16g load) and I will pattern it purely to see whether a reduction in shot charge produces any noticeable improvement in performance (obviously remembering that there are many other factors that will also influence the pattern test results).
Fiocchi Magnum 19g / #7½ (Italian) & 18g / #6 (Italian)
My research into the extraction of best possible performance from my new .410 is not, of course, done in isolation. Opinion on the major UK shooting forums, both past and present, has always been that the Fiocchi “Magnum” loading is the “go-to” loading for people serious about hunting with a .410.
Although I had never attempted wingshooting with a .410 until the arrival of the Yildiz, I found the 19g/#7½ load to be an excellent clay-buster with my previous .410 – back in the days where I still could afford to spend £50 on a morning’s entertainment! I always recall, however, that it was a little sharper on the shoulder than I’d generally prefer in a small gauge gun.
It’s not so much that I mind recoil – my 12 gauge doesn’t come out of the cabinet for less than a 39g cartridge, which I find surprisingly manageable – but more that if one is going to use a lighter load, one expects consummately less recoil with it. In defense of the cartridge, however, the sharpness of the kick may have something to do with the facts that the gun fitted poorly and – if memory serves – weighed less than 5lbs.
I digress. The #7½ (an English #7) version of the Fiocchi cartridge should give in the region of 225 pellets to play with and, whilst I haven’t had the chance to open one to look at the contents yet, I’m told has a full-length plastic wad, which should be a boon to performance as it’ll protect the shot from deformation against the barrel wall to some extent. I am greatly hopeful that this will be “the one”.
The #6 version of the Fiocchi cartridge is also labelled “2.7mm”, which is an English #5½ – a somewhat unusual shot size by anyone’s standard – which should give in the region of 155-160 pellets in the cartridge. It is just as unlikely as the Lyalvale cartridge, I would expect, to produce the 40-yard pattern I am looking for. However, it is widely employed for bird hunting by of serious .410 hunters and comes highly recommended by several persons whose experience I trust enough to make it worth testing.
Apart from anything else, larger pellets (i.e. #5½) should fly truer, all other things being equal, since they are proportionately less deformed by impacts with barrel, other pellets and choke. Although I believe my understanding of the behaviour of shotguns to be deep and broadly correct, I am concerned that my belief that the use of larger shot (i.e. size #6 and larger) in the smaller bores damages performance does not become a prejudice and in so doing, arbitrarily exclude a range of potentially useful cartridges. I must therefore take measurements and prove that an obvious dearth of pellets in the cartridge will lead to insufficient pattern density at range – hence, buying the #5½s on the basis of others’ recommendations.
Eley Extra Long (Subsonic) 18g / #6
Why, oh why, I hear you ask, would I apparently ignore the experience I have already gained with the Eley Extra Long cartridge in its supersonic #7 flavour and buy another box of cartridges of the same construction which contain fewer pellets and expect them to produce better patterns?
Well, dear reader, I’ll admit it: I don’t really expect this version of the Eley cartridge to offer better performance than the previously tested loading, but there is a method in my apparent madness – or at least a handful of things that make me think that this is a cartridge worth testing.
You’ll note from the subtitle that this is the subsonic version of the “Extra Long” cartridge. Yes, it’ll have a rolled turnover rather than a crimp. Yes, it will contain a thin fibre wad that offers barely any cushioning of the pellets under acceleration. Yes, most of the pellets will get scraped up the barrel as the cartridge is fired.
What’s also true, however, is that those pellets will be accelerated more slowly, to a velocity 400fps lower than the supersonic version of the cartridge. Yes, fewer of them will be cold-welded and damaged under that acceleration. Yes, they’ll scrub the barrel walls 25% less quickly. Yes, they’ll hit the choke 25% less hard. Yes, they won’t experience the turbulence of acceleration through the trans-sonic region and back again.
It is for these reasons that, by all accounts, subsonic cartridges tend to produce far superior pattern performance to an identical load accelerated to supersonic velocity. There is little concrete information to go on, but the best source I have suggests that in most cases, improvements of 10-20% pattern density can be achieved simply by lowering the muzzle velocity of a cartridge to below the speed of sound. Twice that degree of improvement is apparently not unheard of.
Now it may be the case that even a 20% improvement in performance will not get these Eley cartridges to produce a usable 40-yard pattern. Given that the shot size is #6, I’d need them to produce a genuine full-choke performance of 68-70% to achieve what I’d consider to be the minimum acceptable pattern density (120 pellets in the standard circle) at 40 yards. No cartridge I’ve tested thus far has even approached that kind of performance.
Furthermore, on the basis of my own experience, I’d prefer at least 140 pellets in the standard circle, which represents an 80% performance for this cartridge: I’m not convinced that kind of performance is achievable on a consistent basis in a .410, even with a subsonic loading. However, I am interested enough in the possibility that I will test these cartridges, if only to have some real-world data to fall back on when I next need to argue for or against (as the case may be) the use of subsonics.