• The AGN App is ready! Search "Airgun Nation" in your App store. To compliment this new tech we've assigned the "Threads" Feed & "Dark" Mode. To revert back click HERE.

Tuning FX Royale 500 and Huma Regulator

Jump to latest Follow Reply
W

Widget23

Member
Dec 4, 2016
161
2
TX, United States
So I decided to replace the stock installed (by AOA) FX regulator with a Huma in my Royale 500, 0.25 caliber. I'm using JSB Exact Heavy Mk II, 33.95 grain. I am using the new FX Radar Chronograph. This is a older Royale (circa 2015, internal regulator, 3 position power wheel only). Power wheel is position 3 (3 dots).

I did everything according to the instructions, so far so good. The Huma regulator is set to 140 (which is the default it came set at, if that matters). 

I'm just not getting the magical 840 ish FPS that everyone seems to want to get with this pellet. I am seeing like 770s-780s. I was seeing only like 760 with the FX reg.

I just did a test to see where it drops off the regulator, and it is dropping off at around 110-115 bar. I filled the gun to 165 bar to start, and was able to shoot 41 shots before it started to drop off! That 110-115 bar is both the gauge on the gun, and when I hook my tank up to fill the gun, it also opens the gun's fill valve at 115 bar (reading the air tank's accurate gauge), so it seems those are the same reading.

Ideas on what is going on? If the reg is set to 140, shouldn't I see the velocity drop off at the pressure?

I tried to raise the reg to 150 bar but that actually seems like it lowers the velocity. 

Thanks in advance....
 
The velocity should normally increase some after you are off the reg, then decrease. So when your gun drops speed at 110-115, the reg might be higher. If you say the speed dropped when you increase the repressure to 150 bar, you might have the reg set to high at 140 bar also. You have to check if the hammer spring is strong enough. If the velocity can be increased when the gun is filled above regpressure, then that might solve the speed issue. If it can only be decreased, like if the hammer spring is turned all the way in, and lowering spring pressure decrease the speed, then you might have to high repressure. To find out if that is the case, the velocity should increase when you go off the reg, with hammer spring still turned all the way in. If you can reach the desired speed as the gun falls of the reg, you probably has to lower the reg pressure.

Basically if the velocity increase when going off the reg, with hammer spring turned in all the way, and the highest velocity measured as pressure drops off, will be the max speed your gun is capable off.
 
Upvote 0
Sounds like you have too low of HST (hammer spring tension) If I can, I try to tune my guns so that the transition off of the regulator is not even noticeable. That's not always possible... But it's nice when it is.. Because you will pick up a pretty sizeable quantity of shots. So, that may be what's happening. Not normally likely, but given the power you're getting.... might be more likely than not.... I would try and add some HST if you can, and see what it does.
 
Upvote 0
The HST lock nut will unscrew. If it doesn't break free with reasonable torque, apply heat.

The pressure scale on the Huma reg is, at best an estimate. If you can't reach the desired velocity at around 95% of maximum hammer spring tension, you need to bump up the reg set point. You have to be able to adjust the hammer tension to tune the rifle. Get a jam nut from FX service. You can then lock the adjustment nut without any locking compound.
 
Upvote 0
Heat gun or propane torch like said above to break the HS adjuster free, some mild porting of the transfer port will help some too. Should be able to get to 850 pretty easy with those two things.

Make sure you use metric tools on this gun, everything is metric. 5mm for the HS adjuster.

You also gain a bit of plenum with the smaller huma reg. I got mine to 900 with some mods (60fpe)





https://youtu.be/6JQqP_-1VYo




 
Upvote 0
Sounds like you figured out the regulator's factory setting was off quite a bit already. I'd think 145-160 probably would be a good range but as others have eluded to you you'll have to increase the hammer energy as well. Also, the 500 I had which was probably older than yours wasn't regulated and didn't have a power wheel. It was originally equipped with a smaller valve so that might be something to think about if yours is the smaller size (good chance it isn't though), I changed that out to a larger seat and stem and it made a huge difference. I also had AOA install a FX regulator before I started modifying it a little and that's when we found out about the smaller valve after I got it back and increasing regulator pressure didn't make a lot of difference. I then moved on to a Huma which gained me a little more plenum and power. Seems like a life time ago but here is a link to a thread on my guns transformation. https://www.airgunnation.com/topic/supercharged-my-fx500-royale-thanks-weatherby/?referrer=1

Jking
 
Upvote 0
Thanks for the information.

This gun has the Loctite on the HST adjuster nut, so trying to make an adjustment there might be an adventure (one that might be not worth attempting, maybe). I've read elsewhere on this forum of people having to basically cut it out and get a new one.
Click to expand...

You really need to use the hammer spring tension. Adjusting the gun with regpressure alone is almost impossible. Increasing regpressure alone will almost certainly lead to velocity drop. The reason is that when you increase pressure without increasing the hammerspring, the increased pressure will make the valve harder to knock open, and less air gets into the barrel. So the hammer need to hit harder. 
 
Upvote 0
You must log in or register to reply here.
Top Bottom
Back
Home
Forums
Resources
Menu