Benelli Crio.  03 December 2002

There are few things that are wholly new in the guntrade most ideas have been used before in so me form or another. Benelli are one manufacturer that do have very open minds when it comes to design and the manufacturing processes that they employ to produce their guns.

Their latest clay model is the Crio and although uses the same inertia principle to work the mechanism, as all other Benelli's. it is a very different looking gun and uses a manufacturing technique that is relatively new to gunmaking, nd to my knowledge has never been used in the manufacture of a shotgun before.

Namely the cryogenic treatment of the steel that has been used to make the barrel and choke tubes.
Most people will have heard of cryogenics as the thing that very rich, slightly mad Americans do when they die. Their bodies are cryogenically frozen and kept so that they may be brought back to life at some stage. I guess if you're rich enough, you haven't got anything to loose.

However, from a gun manufacturing point of view cryogenic treatment has been used in rifle barrels for a few years now, mostly in the USA, to make them more accurate.
Basically, what happens with a rifle barrel is that the barrel itself is frozen in liquid nitrogen which is approximately -195 degrees C. the barrels are taken down towards this sort of temperature. The effect of this is to give a fine and uniform structure to the steel.

In the normal manufacturing process of rifle barrel making heat treatment is carried out on the barrel after which the barrel is quenched. Due to varying thickness in the barrel contour as the barrel is cooled rapidly under quenching, so stresses are introduced into the steel. These stresses start to show up as the temperature of the barrel is raised during repeated shooting, which can cause groups to wander or open up.
What the cryo treatment does is refine the grain structure of the steel to its finest and most uniform state so that the stresses are relieved from the barrel.

When put in the context of the Benelli Crio the cryogenic treatment to the barrel and the choke tubes means that as the barrel heats up during use there is less distortion on the shot as it passes through the bore and the choke. The barrel is more dimensionally stable and this translates into better and more consistent patterns. This is because there is less deformation to the shot load on the periphery that touches the wall of the bore.

The choke tubes have been made longer to give a more gradual transition of the shot through them.
The other benefit to the barrel is the greater resistance to wear. Chamber length is 76 mm which goes hand in glove with magnum proof, so with the exception of high performance steel loads this gun will accept pretty much anything.

The other feature of the barrel is the use of carbon fibre to make the rib. There are numerous benefits to this:

The rib is much lighter so lessening the overall weight of the gun. And makes the gun inherently better handling.

The rib is a greater dissipater of heat so there is little or no chance of heat haze when shooting on those very hot days.

And the rib can be relatively easily changed should it become damaged or perhaps a different configuration is wanted.

The action of the Crio remains unchanged in that it is working on the proven formula of Benelli's inertia bolt system.

The whole working of the Benelli is around the bolt. Basically what happens is this;

When the trigger is pulled the hammer falls onto the back of the firing pin and so fires the cartridge at this point the hammer also releases the magazine stop allowing a cartridge to be released backwards and sit under the bolt. The bolt is, at this point, still in the forward position. As the cartridge is firing and causing a great deal of backwards force this causes the rotating locking head of the bolt which is engaged with the recess in the back of the barrel to lock up completely. In other words as the gun as a whole is moving backwards under recoil, so the bolt is moving forwards to counter it. In effect the bolt is staying still as the rest of the gun moves backwards around it.

This causes a large spring within the bolt to compress and store energy. As the force of the fired cartridge dissipates the energy within the bolt spring takes over and throws the bolt backwards, so releasing the rotating bolt head and ejecting the fired case. The second cartridge has been sitting under the bolt and is immediately brought up by the carrier and the bolt comes forward again to take it forwards into the chamber.

This may sound a little complicated, but it really is simple physics. The net effect is that we have a semi-auto shot gun with fewer moving parts, which overall is a good omen for long term reliability. And with no gas flying about under the forend it is not only slimmer in that area, but there is far less muck and powder residue to clog the mechanism so there is less need for cleaning.

The cover for the bolt itself is made from a separate piece of black anodised aluminium, which gives a nice contrast with the action frame. It is separate from the rest of the action frame an is held secure when the barrel is assembled on the gun.

And the action frame is made from aluminium alloy that is in turn nickel plated to give an attractive satin finish.

Woodwork is very good on this particular gun, both in quality and finish.

It is tight grained American walnut with very good figure both in the stock and the forend. One feature of the Benelli's in general is that because of the inertia bolt system there is no mechanism working under the forend wood as in a gas semi auto. So there is no movement in the forend and more noticeably, the forend slimmer than most OU guns.

The stock has Benelli's usual 3 position adjustment for drop so it can be made to suit most shooters.
The chequer is particularly well cut and I would say is almost certainly machine cut.
I think that the stock is a little short at a fraction under 14.5". And is finished with a thin black rubber pad which is comfortable. Nearer to 15" would be better for most. I also thought that the top of the pistol grip would be better a little deeper in front of the comb to allow a slightly more comfortable grip, but that may just be me.

Overall, I think that Benelli have come up with something different that does have something more to offer than the autos we are used to seeing set the standard. It is light and points well. It will need far less cleaning than a gas auto. And it also is distinctive looking.

It comes in a ABS case with stock shims and extra chokes.

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