Air Arms Owners Club

Have just ordered myself one for my MPR, was just browsing their website and got carried away.

Anyone here have any experience with them in a s400/500?
Just had a look at the installation video and it's very easy with no drilling involved.
I know raj has one in his s200 that he was very happy with, so hopefully as good in the s400's

Only £66 with free postage from CZ, fairly reasonable price I reckon.

Hi Stoohundred,

My S400 classic has an Altaros regulator inside.
After some fiddling with the reg pressure i am a very happy bunny!.
Consistacy is great, +- 0,75-1,0m/s extreme spread is possible.
Reg pressure shlould be in the range of 105-100 Bar, then use venturi screw to set speed/energy at legal level.
Be prepared to tinker a bit and invest about one complete 12L 300bar air tank while doing so.
It aint a drop in and forget set, but neither a Rob Lane (Lancet) nor a HUMA reg are.

Kind regards,

Robert Hermens

Thanks Robert, do you know what pressure they come set at? And is it stated or marked on the reg?

I read on another thread somewhere that they are set to 120 bar as standard but as you said, I think I will want to set it to around 100 bar.

Is this easily done accurately and are there any markings on the reg to set it to?

Keep us posted on the outcome as this is something i've been looking at doing to my MPR FT too.

Zeewulf wrote:Keep us posted on the outcome as this is something i've been looking at doing to my MPR FT too.

Yeah will let you know, only ordered it today tho so may be a few weeks.

To be honest , My MPR dosent really need a reg, I have added the longer HFT 500 cylinder tube to it so I now get about 65 shots IN THE SWEET SPOT between 160-110 bar, with a maximum of 12 FPS spread.

I was just browsing the website earlier and got carried away.

Hopefully will be able to get the FPS spread down below 10fps and will get loads more shots .

Any results yet ?

I fitted one on the makers settings and got 11.4 quite consistently. Even after standing the gun for three weeks it still gave the same readings. Not bad at all.

I'm not a tuner. But my understanding is you should not really fit a reg to an AA S400 series unless its an absolute lemon. Talk to AA about their views on regulators and why a polish and lube is, on the whole, all you need. No regulated gun I have ever encountered has out performed my non-regged AAs (in terms of fps variability in the sweet spot) over the chrono or bench rest shooting and that also includes every HW100 my mates have owned....

Some tuners have told me that although regs give more shots, their variability is greater over the sweetspot.....its up to you as to whether that's an advantage.

Dr B wrote:Some tuners have told me that although regs give more shots, their variability is greater over the sweetspot....

Strange Because my regulated rifles do not have a sweet spot - the whole of the fill is the sweet spot. And there is no variability increase ... I found a big decrease in shot-to-shot as well as max - min spread.

I agree Raj,
that's the whole idea of a regulator in a rifle. They are designed to shoot the same over the entire fill. My Webley LiteW8 which was fitted by Phil Crampton of the Rat Works is good right the way through the shot count. All I need to do is get my range to the target and work out my hold over or under at that range.
My Air Arms S200 with the Altaros regulator fitted by myself, was a bugger to tune at first, as I followed the instructions to the letter, which resulted in some high flyers, but once I had sorted out the correct hammer and transfer port settings for my MK1, I am now doing the same with that as with my Webley, as well as getting a lot more shots per fill. A 190 BAR fill will give me 70 shots, while a 200 BAR fill gives about 105 shots per charge. As suggested by Altaros I just dry fire four or five shots then its within around 5 ft/per second over the whole of the fill. It is now shooting this at 11ft/lb. I found that if I tried it much above 11.3ft at the settings of the current rifle, then it would get high flyers again. I will definitely go the regulator way in the future. Unless you've tried it, you'll never know the difference, and at just £63 for the Altaros regulator its great value. Add another £100 to get one professionally fitted. The Humma and other varients are no more than £25 more than the Altaros. I only went Altaros so that I didn't need to drill a hole in my air cylinder.