Powered by liquid gas the Umarex 850 Air Magnum air rifle was the world's first mass produced, full-power Co2 hunting rifle
As you know, the legal limit for an air rifle is 12ft/lb – but when Co2 is used as a propellant it can easily produce an air rifle that goes beyond this.
I took a look at German Umarex, who are Co2 power experts, offering this mass-produced and highly affordable 12ft/lb Co2 powered rifle.
The 850 Air Magnum has a slim pistol grip with raised dots which will enhance the grip. The cheekpiece makes it suitable for both left and right handers and it has a ventilated thick rubber butt-pad. The stock is black synthetic material.
Despite being called an Air Magnum, the gun is powered by a removable and renewable 88gram tank of Co2 (88g Co2 AirSource). This is housed and secreted from view by the fore-end.
To access the inlet valve coupling to power-up, the front third section of the fore-end has to be removed. This is achieved by using the release catch found underneath the stock at the point where the jointed fore-end meets. The slotted push-in catch allows a firm thumb hold as you press inwards and push forward.
When the end cap is removed, it reveals a cavity into which the AirSource tank screws. This is half-covered to the human eye, and when the front section is pushed back into its original position, it is hidden from view.
You need to dry-fire the rifle in a safe place once you have screwed the canister into position, as you would with a low-power Co2 pistol. This is to ensure the canister is fully pierced and the Co2 feeds freely though the inlet valve and all rifle internals.
I thought that the action of this rifle was particularly well designed. After pushing forward the cocking bolt, the action takes the magazine retaining catch forward to secure the eight-shot rotary magazine and probes a pellet into the breech. This operation is gratifyingly smooth.
To load, the blacked-steel cocking bolt is a generous, chunky size and needs to be lifted up from its original forward position and pulled fully rearward. This locks in position and allows you to operate the magazine retainer, which is the lengthy, slim catch found directly behind the magazine on the right of the action.
Red dot indicates the rifle is ready to fire
The T-bar-style automatic safety catch will still be protruding out from the rear of the action block, indicating the rifle is safe. The automatic trigger safety is sensibly sited at the rear of the action block (ideally positioned for operating with the thumb of the shooting hand). You will know when the rifle is ready to fire as a red dot on top of the action base-plate now shows.
After you have taken a shot and then want another pellet in the tube, you just lift and pull back the cocking bolt (the rifle is now cocked, and automatic safety is back on), and simply cycle the action back. When the magazine is emptied you remove it by pulling back the cocking bolt and sliding back the magazine retaining catch to remove the magazine. You then can repeat the loading procedure.
The rifle already features a decent pair of fibre optic open sights, up to the task of kill-zone accuracy from 12 to 15 yards. However, it’s when you fit a pair of optics to the scope rail that you really see what this rifle is capable of.
To give you an idea, with a Walther 3 – 9 X 44AO IR Night Pro in high mounts, I’d zeroed at 25 yards and was soon making ragged 1-4in groups at the set zero, shooting bench-rested.
If you’re a skilful shooter, you will discover that the Umarex 850 Air Magnum has a kill-zone accuracy to 35 yards and beyond. I am impressed by this and it is a leap ahead in the design, function and availability of a Co2 powered air rifle for hunting.
Economical and viable
Co2 makes an extremely viable alternative for hunters looking for a rifle that has the benefits of a recoil-less PCP, without the need to buy a diver’s tank or go for re-fills. You should get 140 full power shots per 88g AirSource tank so the gun proves economical and viable to run.
I fitted the Air Magnum with a muzzle compensator for this test to keep report to an acceptable level. However, special sound moderators are available to keep this rifle silent.
My final opinion?. This rifle is impressive, highly accurate and a pleasure to handle. It’s popular with pest controllers who use it for feral control.
I was very impressed by the Umarex 850 Air Magnum. Its accuracy is on a par with most conventional PCPs, it's lightweight and good value for money.