Tuning Tuning my FX Crown

I purchased my Crown about a year ago. I have done nothing to it but shoot it. I have not adjusted anything but the scope to sight it in. I shoot the JSB Exact King at 25.4 grains. The same pellet I shot out of my Air Arms S510 before I sold it. I am able to shoot 45 yards in my back yard and I constantly get one ragged hole. Now most people will tell me to leave it alone, but most you airgun buffs know you just cant do that. With all the different pellets out there, and slugs, I would like to try something else. I want to try also to do some adjusting to my Crown. There is two wheels on the left side of the rifle. The one is set on 25-30 caliber, and the other wheel on the MAX setting.
What happens lets say if I turn the forward wheel to the .177-.22 setting? Lets say I turn the rear wheel to a lower setting off the MAX setting that it's on now. My thought is this...I will probably lose velosity, but I will probably gain more shots per fill. I do not have a compressor, nor a hand pump, and so I depend on having my 4500 PSI tank filled at my fire department. Most of my shooting is at Pigeons, and small rodents that do not require as much energy to dispose of as my Crown has to offer. I would also like to try the GTO pellets just to see how they work in my Crown.
So what do I do? Just experiment with the power controls by moving them? Will I be able to obtain more shots per fill by turning them to a lower setting?
I would like to hear from you!! Thank you
 
If you don't have a chrony, get one before you start fiddling with the gun. The forward wheel adjusts the aperture of the transfer port. While turning this down will slow your shots and possibly give you more shots per fill, so will turning the hammer wheel down. You won't know which one yields better results without the chrony.
 
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First, (after purchasing a chronograph), what is your goal or what do you intend to achieve by screwing with all the controls on the gun? Do you want to shoot slugs, more power, better accuracy, longer range shooting? Or are you just enamoured with all the posts here about guys tinkering, fiddling, screwing and messing up their guns? Sounds like you are happy with the way it currently shoots, so why mess with it? You may never get back there. Trust me, been there, done that.
 
First, (after purchasing a chronograph), what is your goal or what do you intend to achieve by screwing with all the controls on the gun? Do you want to shoot slugs, more power, better accuracy, longer range shooting? Or are you just enamoured with all the posts here about guys tinkering, fiddling, screwing and messing up their guns? Sounds like you are happy with the way it currently shoots, so why mess with it? You may never get back there. Trust me, been there, done that.
I would like all of the above. My accuracy is definitly there, but I wouldnt mind just trying a slug or two. If they don't shoot, then thats that. I have a 700 barrel because my gun is a contiuum. I wouldnt mind doing some 100 yard shooting or so sometime also. Wouldn't mind trying some of those GTO pellets either, but that would probably exceed the sound barrier. Just thought by using these, and reducing the power that they might work.
 
The Crown is pretty easy to play with and not mess things up. However, as had been said above, you need a chronograph to be able to do it correctly. If you make a note of your starting positions then its pretty easy to get back to where you were at the beginning.

I would recommend not messing with the hammer spring pre-tension at first. Just use the hammer wheel and transfer port to start. Then, if you can’t achieve what you want that way you can also start messing with the regulator pressure. These three gives you a wide latitude to adjust your tune and you do not need to remove the stock and mess around with fiddle little things like the (tiny) ball bearings on the inside of the hammer wheel, or the little springs that press against said bearings.

Between the hammer wheel, transfer port, reg pressure and different pellets and pellet weights there is a world of possibility and little risk to screwing up your gun. Just go slow and take notes.

And have fun. But beware, its like Crack Cocaine (or so I’ve heard, since I’ve only tried FX airgun tuning and not crack 😂). Once you start its hard to stop.

Chris
 
Record all your current settings especially the speed of a chosen projectile that you have found more accurate in your gun. That would be your baseline to return to if you don't get better performance out of your gun after you do some tweaking.

What your want to achieve is the "Harmonic Tuning" where you get the best shot counts and accuracy with a selected ammo. A holy grail once you find that perfect REG/HS combination. It will be a lot of hair pulling and stress once you have decided to go down this path. But making adjustments and learning your tool is part of the fun with this crazy hobby of ours.

Good luck.
 
A lot of my shooting is around my house removing chipmunks. My gun is 25 caliber, a bit overkill for these rodents, and I also have a couple houses next to me that I dont want to risk a ricochet. I was thinking that if I went to a light pellet, like a GTO, or something in that weight class, and adjusted my back wheel on my FX Crown, that I could get my velocity down, and also not be throwing a 25 grain pellet around.
I think this is good reasoning, but until I try it, I won't know.
Furthermore, I dont really have an easy way obtaining air. I plan on getting a hand pump, but also heard it take a lot of effort to pump up a rifle. My shooting is very sporatic, and I feel that it wouldnt be that difficult to use a hand pump. I probably don't shoot my rifle probably 20 times a week.
 
I had a tuning session with my Crown this morning. Upped my regulator from 115 bar to 125 bar and therefore needed to up my hammer spring using the Power Wheel. Please know that if you adjust the regulator much, you will likely need to remove the stock in order to make an adjustment to the hammer spring preset tension. It's not that hard, but some shooters prefer not to remove the stock. I just thought you should know. My gun is a .177 and it is now shooting the JSB 13.43 MRDs around 850fps and the accuracy increased pretty dramatically. My prior tune was shooting the same pellet at 800fps. The extra speed must be increasing pellet stabilization. Keep us posted.