Last week ST?s firearms guru Bruce Potts got to grips with what he described as the ultimate fox rifle, custom built by leading gunsmith and engineer Steve Bowers (Bowers of bliss, 2 November). On paper, it sounds very impressive: the rifle sends a 39-grain bullet from a .20 PPC round through 22in barrels, which have a three-rifling groove one-in-11 twist format, at 4,000fps with 1,385ft/lb of energy. But for those of us who aren?t fluent speakers of ballistics, what does that mean? Does the thing actually work?

The only way to find out was to see it in action. The owner Nick Corbett uses this tool regularly on various estates in Buckinghamshire and Northamptonshire where he helps out gamekeepers and farmers with their fox and corvid control, and he kindly invited ST on a foxing mission in August.

Indeed, we went out twice in a week, as the first trip returned a blank. That night, we drove round the large perimeter of the estate near Milton Keynes, with keeper Jonathan Baxter at the wheel of his Mitsubishi, operating the lamp for Nick, who leaned his rifle on a Dog Gone-Good window rest. Every 10 minutes Jonathan would pick up a set of eyes across the flat stubble fields, but a closer look would reveal a rabbit, hare, muntjac or roe deer. Eventually, we rounded on a pair of bright orange eyes at the boundary of the estate, near a wood where Jonathan knew an old dog fox operated. The eyes would not stay still, however, moving on whenever the lamp lit them up. Eventually, they disappeared into the wood to shine another day.

?If I had rushed, I could have probably taken a shot at that fox,? Nick said afterwards. ?But it is never worth it, unless you are spot on. It is very likely that someone did exactly that and missed that old fox some years ago. It would explain why it is so lamp shy.? ?I suppose it is good news that we have only seen one fox,? Jonathan added. ?I think it is more likely that we have been where they are not, as there are certainly plenty of them about. It has been a lean year for rabbits this year, though ? we seem to have more munties than rabbits ? so maybe it?s a lean year for foxes too. They?ll come back, though ? they always do.?

One-nil to Charlie. We were no closer to finding out whether this bespoke fox rifle could do the job it was designed for. Perhaps therein lies the paradox that faces anyone that goes in pursuit of the fox ? you do not want vermin on your ground, but if it does not turn up, it is slightly disappointing.

Undaunted, we met a few days later at a different farm in Buckinghamshire, where Nick helps the keeper Eric Cross with fox control. Again, the estate comprises a decent acreage of fine arable land with stubbles that offer a hunting paradise for the red peril. It was on the higher ground that we started, overlooking the vale beneath us. These steep hills offer ideal grazing for livestock and natural height for pheasants to fly over Guns below. Of course, the pheasants are also highly palatable for Fantastic Mr Fox.

Nick has long learned the best place to lie in wait for these accomplished predators as they begin their evening hunt. Four roebuck scarpered as we approached a grassy knoll at the base of a wide gully beneath a wood. We were sitting on the stage of an enormous amphitheatre whose sides reached up steeply, providing a natural background for a shot. The trees wrapped round the slope like a curtain and as the sun began to set, we scanned the woodland edge for signs of life.

Nick had also set up a Foxpro call simulator, which looks like a camouflaged ghetto blaster. The American gizmo can make any number of animal calls that will attract predators or prospective mates. Of course, the vast majority are more applicable to conditions stateside, such as a bobcat in heat or a prairie dog in distress. However, a squabbling crow or a feeding mallard sounds the same no matter which side of the Atlantic you are. Nick had set the remote-control to ?partridge in distress? and we lay flat on the grass as its plaintive cries interrupted the silence.

Nothing stirred. In the distance we could hear a patient dog owner putting her retriever through training exercises, but there was no movement in our immediate vicinity. The shadows continued to lengthen until it was too dark to see suitably with the naked eye.

?You?re turning into a bit of a jinx,? Nick said, unloading the fat, stocky cartridge from its chamber and holding up the single-shot rifle for us to see it was empty. ?That?s clear now. We?ll see if we have better luck tonight with a lamp.? Two-nil to Charlie. We retreated to the farmhouse, tails between our legs. Happily there was a large pile of freshly baked scones waiting for us, expertly made by Eric?s wife Anne. We devoured the lot, seeing off a pot of tea and the entire contents of a pot of homemade raspberry jam. We waited for darkness to fall.

As it happens, we would have waited all night. A round, high moon shone from a cloudless sky, illuminating the fields like a spotlight. Even at 11pm, we could have played 18 holes without difficulty. This only added to our run of bad luck. ?I?m afraid these could hardly be worse conditions,? explained Nick, phlegmatic as ever. ?It is so still that any sound we make will carry. You ideally want a dark night with low cloud and a bit of wind to hide your noise. The fox is in the same boat, of course, as he is out hunting too. He can be bolder on a dark, windy night, as his prey will not see or hear him. Tonight he will be edgy, if indeed he comes out at all.?

But it was a good night for photography, if not a lot else. For the best part of an hour, Eric kindly drove us about the fields, forsaking a deserved bed after countless early mornings feeding his birds. Both he and Nick came armed with a lamp, but there was nothing stirring. Nick did once manage to light up a pair of yellow eyes, but they quickly disappeared over a wall. It could very well have been a local farm mog out on a forage ? we would never know.

?We?ll try one last set of fields,? Eric offered, eating further into his brief shut-eye. ?They are three huge stubbles by one of my release pens. There?s often a fox or two by there. I lost about 40 poults in one night to a fox that wriggled in. It was a massacre.? En route, Nick explained why the rifle had been such a success. ?First of all, it is entirely customised to fit me, so it is extremely comfortable to shoot. It is a heavy gun, which can be a burden, but that means it doesn?t shift at all in the shoulder, and I can see the bullet hit the fox. The accuracy is unbeatable. I zero it at 200 yards and, at anything up to 300 yards, you need only aim at the engine room and it will be effective every time.

?I use a light 39-grain bullet, which shatters on impact. The insides of the fox will be practically liquefied and it can be like picking up a bag of sand. The sole purpose of the rifle is to kill vermin ? it is nothing to do with harvesting an animal for the table ? and this is the most humane method I have come across. The fox has no idea what hits it.?

Added to the accuracy is an absolute confidence that the aim will be true. Home-loading, bench-testing and repetition have reduced any variables to their minimum. ?I am nearly always out lamping on my own, so there is no glory in taking long distance shots or showing off by aiming at the head. It is all about doing a job for a farmer or keeper. I enjoy it, of course, but most of that enjoyment comes from doing the job properly.?

Crows often provide a stiffer challenge than the foxes, as they can be harder to approach. Nick will shoot them up to 400 and even 500 yards away with little difficulty, though there will be adjustments made for wind-speed, humidity and gradient where necessary. ?You need to know your terrain and your rifle intimately if you are going to be successful at that range. Again, the .20 PPC is extremely accurate. But I have to get it right first time. A rabbit will stay put if a bullet passes over its head, but a crow is clever enough to sense something is wrong, even though it cannot see you.?

Tonight we were after foxes, however, and the final whistle was fast approaching. Nick and Eric shone their lamps across the middle field. Bingo! Wordlessly, they switched them off after Nick had picked up a pair of eyes by a hedge on the far side. It was a fox out mousing. Slowly, the Rifle gestured with an outstretched palm that we get down. He led by example, setting the rifle down on its bipods and crawling in behind the stock.

Eric sent the beam of his lamp over to the hedge and the eyes lit up again. I waited for the phizz and thump of the bullet, but it never came. The fox had not settled but had moved to the other side of the hedge. Nick dared not attempt a shot through vegetation as the bullet would disintegrate on impact with the smallest twig. Yet not all was lost and, as though telepathically, keeper and fox controller were quickly on their feet again, skirting along the bottom of the field to reach the hedge.

Nick was again on his belly and we followed suit. Eric lit up the other side of the hedge, before scanning across the field. Our fox was still there. The light went out as Nick eased himself into position. A quick nod and Eric revealed the target once more. Nick has the trigger set to a hair?s weight and will wait to have the fox lined up on the reticule before simply resting his finger against the trigger.

With that, it was over. Or was it? Eric knows from experience that one fox can often bring another and, sure enough, a second pair of guilty eyes shone back near the top of the field. It was a longer shot, but Nick made quick work of it. He would come back the next day with a rangefinder and confirm them both at 260 and 308 yards respectively. ?It is rare that I would take a shot as long as that when lamping,? he said, as Eric retrieved the bodies. Both had been killed instantly to shots that entered a couple of inches behind the shoulder. ?The slope gave a natural backstop and it is almost like daylight out here. Such is the accuracy of this rifle I needed only to aim where I wanted the bullet to go and it did.?

For Eric, the venture had been well worth halving his sleep allocation. ?They?re both youngsters, possibly from the same litter, and there?s every chance they both got into my release pen. It explains why there was so much carnage in there. I?m delighted to see the back of them.? So the rifle does work after all and not just on paper.

For more information contact Steve Bowers, Specialist Rifle Services, tel (01242) 863005 or visit www.specialistrifleservices.co.uk