The advantages of reduced-load .22 rimfire ammunition
If you’re shooting in and around outbuildings, you need a round that doesn’t ricochet. Bruce Potts looks at reduced-load .22 rimfire ammunition
Low-velocity and low-noise rounds such as the RWS Z Lang and CCI CB Long make sense when you are shooting around farms, barns and outbuildings
With cattle in the barns and grain stored over the winter months, it seems an endless task to keep hungry vermin species at bay. As soon as I have to battle against colder and wetter weather, most of my vermin control heads indoors — in and around the barns and outbuildings now become the hot spot for contact with vermin.
As the task becomes a little easier with covered protection, so the danger increases with ricochets or collateral damage to windows, machinery or livestock. Here, an air rifle seems the logical answer — and it usually is — but I like to use some reduced-load .22 rimfire ammunition, which means I can still use my .22Lr rifle.
The RWS Z Lang is a suitable round for squirrels and rats
Load up
For years I have been using reduced-load .22 rimfire ammunition, such as CB (conical ball) and BB (ball bearing) caps that are loaded one at a time in a bolt-action rifle. But these are not always available and accuracy is only good over very short ranges; conversely, they offer limited overkill or risk of ricochets. I really like the CCI CB Long rounds. They’re shorter than a normal long rifle round but share the same case size; the lighter bullet in the Long version is 29-gr, not 40 grains. Therefore these feed better in a magazine and give better accuracy, and a safer shot in a confined space compared with standard rimfire rounds.
The .22 Shorts are good, particularly for use in bolt-action or pump-action rimfires that have tubular magazines because these feed the short rounds reliably. You can usually load 22 at a time so they are excellent for scurryingrats. Another round I have been experimenting with is the RWS Z Lang, (available from RUAG), which is a consistent performer. It is a .22 rimfire round that shoots a 29-gr lead bullet at 850fps velocity for 47ft/lb energy. It is part of the Field range and, because it’s made by RWS, you know that it will have dependable accuracy. The Z Lang means Zimmer or Room Long (which refers to overall length of round). It is intended for use on short indoor ranges, but might be good at double-duty vermin control too.
True, it is a round-nose solid lead bullet but, compared with a similar .22LR subsonic round, the reduced velocity might make it much safer to use. You still have to be careful with your shot and,
as with all rimfire-use and air rifles, you need to make sure you have a safe backstop, especially with non-expanding bullets like these.
Actual ballistics
I took 10 rounds, weighed them, then removed the bullet and weighed the bullet and powder charge, and measured the velocities. Accuracy was conducted at 20 yards — the sort of range I was going to use these rounds on — then tested in ballistic media compared with an air rifle, my normal CCI CB Long and .22LR Eley subsonic round. I initially used my trusty Sako Finnfire.
To enhance the RWS Z Lang round, I shot it in a fully moderated Sako SSR.22Lr rifle. This has a ported barrel just in of front of the chamber and drops a high-velocity round to that of a subsonic— 200fps velocity drop. With the Z Lang, you have an even quieter and lower- velocity round, which is less likely to over-penetrate your quarry than a normal velocity rimfire, providing a safer shot that retains accuracy. What I like about a .22 rimfire-based vermin short-range gun over an air rifle on some occasions is that you can reload extremely fast, and it gives you FAC-rated air rifle velocities and energy levels.
I still like to use air rifles and FAC-rated ones, but sometimes it’s just easier to use a low-velocity rimfire round, or at least keep a spare mag with some in case the shot presents itself. However, look at the results: 858fps and 47.4ft/lb for the RWS Z Lang from the Sako Finnfire rifle. Though the accuracy was superb at 0.45in at 25 yards range, I had total penetration in the ballistic media. That’s because the bullet did not deform due to the round-nose lead profile so momentum pushed it through. Recovered bullets looked in perfect condition, with only the rifling engraved to the bullet’s bearing surface. Where the velocity was reduced by the Sako SSR’s ported barrel to 655fps and 27.6ft/lb over 12 yards, there was still total penetration, but at 25 yards it stuck at 6in.
The only real difference between the two velocities was a secondary cavity at 3in and 6in in the media at 12 and 25 yards respectively from the Finnfire’s 858fps velocity. This was because, at that depth and velocity point, the bullet became unstable and “wobbled” or yawed off course. However, from both guns, that’s a bullet travelling well through any rat or squirrel head dimensions.
The CCI CB Long ammunition behaved in similar fashion, so not a RWS Z Lang peculiarity. Look at the air rifle results — there is good accuracy at 20 yards, 0.40in and only 3.5in penetration at 12 yards and 2in at 25 yards. This means that there is less chance of over- penetration, but where there is over- penetration, most of the bullet’s energy is left inside the target, where it should be to cause maximum lethality.
Reduced velocity
Are you wondering why I don’t use the standard Eley subsonics because they only penetrated 6.5in in the media, less than the reduced velocity rounds? It’s a fair point, but that’s because the lead bullet is a hollow-point design so energy is dissipated from the bullet into the target quickly at a higher velocity. But 6.75in penetration at 25 yards and total at 12 yards means most of that energy — which is more than the reduced-velocity rounds — is wasted outside the vermin’s vital area. So there will be more ricochet.
I tend to use Z Lang’s on troublesome squirrels as they are quiet with a sound moderator fitted, and silent from the Sako SSR. Squirrels can be difficult to put down and a low-velocity .22, with a heavier 29-gr bullet and more than 40ft/lb energy helps to stop them in their tracks and drop them at your feet. I have nailed squirrels with air rifles but they get a death-grip on
a barn’s rafters, only to drop down later, usually when the landowner or his wife are milking the cows.
Conclusion
The true Z Lang round is designed for indoor target use, as it shows superb accuracy. However, after these tests, I might have to rethink my logic about round-nosed solid low-velocity rounds — not the round’s fault, but my poor application. If a Z Lang or CCI CB Long had a hollow-point version, it would be a totally different situation.
With a safe backdrop, as you should shoot anyway, there are no problems but care has to be taken when shooting squirrels in the rafters or rats running between machinery. I do most of this type of shooting with a straw, grain piles or silage backdrop, so a reduced .22 rimfire round still has its uses.
This is where an air rifle really does make sense, with enough power at short ranges for a humane kill but without over-penetration. In a future piece, I will look at 12ft/lb energy air rifles and FAC-rated air rifles to see if there is any advantage between the two for vermin control.
