Forty-one thousandths of an inch is a lot of choke for a 12 gauge and represents really quite a lot of “squeeze” on an already over-sized fibre wad and shot column – especially when it’s a reduction from a bore diameter of .721″ rather than the more traditional .729″, as is the case on my Baikal.
Of course, there are a small number of wildfowlers who believe that steel shot, already generally superior to lead in pattern performance terms because of its hardness, requires chokings of 0.060″ or even 0.070″ to function at its best. The fad for “terror” chokes (and bloody hell the idea scares me) giving constrictions that would make American turkey shooters’ eyes water now seem to be dying out thankfully and not before time. It is quite ridiculous to think that such constrictions could be anything other than damaging, especially when one considers that it is quite straightforward to “blow” a pattern with what many folk consider to be the standard full-choke constriction (c. 0.040″).
Pattern testing today filled out some more numbers for the Fiocchi Flobert #7½ round but, as lots of people seem to say to me at the moment, that’s much of a muchness. I’m not going to hunt with that gun, so whilst it’s theoretically interesting, knowing their performance doesn’t achieve much practical.
On the other hand, supplementary patterning for my 34g/#5 load has prompted a change of course.
Now, to be fair, today’s patterns weren’t as bad as I thought they might have been and – given the difficulty in picking out some of the pellet holes, might represent a slight under-estimate of performance. 159 and 143 in the circle at 40 yards are usable, if not spectacular patterns from the full choke barrel. However, when the half-choked barrel is producing patterns of 191 at the same distance, one has to begin to suspect a blown pattern due to excessive choke and this may be what we saw today.
The trouble with the cartridge, as it’s currently constituted, is that although it does provide fairly smooth recoil and a comfortable shooting experience, performance is mediocre and inconsistent and it does use a lot of powder, a good proportion of which is left un-burnt in the barrel after firing. A0 is really a “magnum” powder and using it on really rather a light load is wasteful.
Since I’ve been investigating loading some “traditional pigeon” shells using A1 – which ought to be a much better powder for 34g – I’m going to abandon the A0 cartridge as unsuitable for the Baikal – at least for now – and see if I get any better results with a different powder. #7 shot is proving hard to get, so 36g/#6 might do for that experiment and – if they turn out to be any good – perhaps I’ll actually end up using them in the field.
Unfortunately, I’m sceptical. Using a faster powder will increase pressures and increasing pressures is likely to damage performance. It may simply be that a tight bore with a very tight choke at the end of it is just too much for any ordinary cartridge and that I’ll have to get the full choke barrel bored out somewhat – perhaps to somewhere between the .041″ constriction it has now and the .017″ constriction that seems to perform so well with the originally-intended cartridge.
We shall see, but given my luck in finding good, performant cartridges for all of my other guns, it seems only fair that I have to do a little work to get one of them printing patterns the way I want them. Apart from anything else, it will get hugely confusing if, all of a sudden, I’m pulling the back trigger for nearby birds and the front trigger for the screamers. That just wouldn’t feel right after several years of using a near-identical 16 gauge that works the other way round…