After looking around for a long time to find the 'optimal' regulator pressure I always seem to find the 85 bar as rule of thumb/golden number for .177 sub 12 ft/lbs. After being busy tuning for the past years I found that these golden numbers barely fit every rifle. I get that this forum is mostly UK based so be very careful not to violate any laws and some common sense is required A cumbersome way to tune is to adjust the regulator in steps of about 2 bar and install every time and do the tests. This means the testing will take weeks and requires exact placement of all the components each and every time. I do it in a different way which is described below. The items you need are: A high precision regulator with a digital pressure gauge A modified steyr air cylinder with a foster style fitting without the valve inside (to prevent effects of a sticking valve) A brass cylinder to replace the belleville washers inside the regulator The digital pressure gauge is not on my external regulator at the moment since this is a way more compact setup and thus easier to take to the range and use it as a tethered fill station. I can imagine that the high precision regulator isn't something you have laying around in the house (in the Netherlands and Belgium a lot of people that shoot our 100 meter airgun competitions actually do have one laying around ). I've done the modification to the air cylinder because I had one without the quick fill and got tired of unscrewing it every time for filling so I took out the pressure gauge and replaced it by a foster style quick fill (best fittings sell them with the M10x1 thread). For matches I have another cylinder with the factory quickfill. To get the steyr regulator to stop acting as a regulator I replaced the belleville washers by a brass inlet and unscrewed the nozzle a couple of turns. In this way the piston can not move and since the nozzle is out of reach it won't seal the regulated chamber. Now all you need to do is put the Steyr back together with the non-functioning internal regulator and quickfill cylinder and go to the range. While on the range you leave the external regulator pressurized and tethered to the cylinder while shooting. A criterium I use to find my optimum is to see at which pressure the groups are the smallest and the noise is reduced to an acceptable level (Steyrs have a tendency to bark like crazy sometimes at lower powers). If you have to buy all this it's not cheap but if you're part of a club with a lot of Steyr shooters I bet you can find an easier and cheaper way (group buy or whatever). This same technique will work for other airguns too but I just don't have pictures of them to show it. Important is that the internal regulator must be at the exact same place as when you normally use it because it restricts the flow from the cylinder to the regulated chamber. If this flow isn't restricted during a shot your results will differ a lot from the actual use case. All internal regulators shouldn't be tampered when set, due to the possibility of losing the seal, but there is a very nice topic in this section about resetting regulators Hope this helps Again, I do not advise you to violate your own countries laws. In the Netherlands we're unrestricted in power so this is no problem for me but a lot of countries do have restrictions so abide by these laws!!! Also do not go above 140 bar for those who are allowed to do so, this is an advice from steyr themselves to make sure the internals are still able to handle it without breaking. And to prove my point, I'm set at 92 bar at the moment (take some inaccuracy into account of the pressure gauge so use the same gauge for finding the optimum and setting the regulator!) instead of 85 bar..