Power Tuning Mods for the FX Crown

@srtmat, the VS will be cheap for you Americans ... to me, Italian, between the expenses for the custom VS and the shipping costs, I will spend $ 35 ... too much for a metal ring .... but if it gives me a little more power (I've read up to 40 ft / p, but it depends on the caliber), it's money well spent.

I have a crown. 25, with a 600 mm slog barrel and the 34 grain JSB have a maximum speed of 803 fp / s. The crown is very precise, but I want a little more power, so I'm going to do all the possible jobs: TP huma, Titanium VS 6.35 mm, double-hole ball pusher, steel hammer with weight from 7 to 9 grams ( I will buy 2 of hammers and cut them to obtain 2 different weights).

For now, the pressure regulator, a generation three, will not change it ... then I will see based on the power to which I will arrive. No, changing only the VS and not optimizing the other air passages, (TP with larger hole and work in the nozzle) will not give much advantage as ft / s

I just received a Huma dual hole transfer port but haven’t had time to install it. I’m going to test and see if the dual port will out preform my modified TP. Pellets load fine but I haven’t tried slugs with it yet. 
I purchased the Huma just in case there are loading problems with slugs.
I just ordered a larger valve seat today as well.

Let me know how domed and slugs load with TP huma. A friend who owns an Impact cal. 30, he told me that his TP Huma did not make him load ammunition well, so he was forced to reassemble his original.

I am new to Fx air guns I have a Dream Tact Compact coming soon and I read some where the this gun is basically a Crown, so would these mods work on that too?

Has anyone been able to tell yet if the Huma TP is better to use or doing it yourself, and shape your own is the way to go. I was ready to order the Huma, but there has been concerns about feeding pellets and slugs, I would like to use slugs. I'm just waiting to see if I should move on or make the order.

Thank you very much in advance,

Eamon

I've had no problems with .22 JSB 25.39 gr. pellets through the Huma dual port in my Crown. Haven't tried anything else...

@BSj, therefore, for your experience, the TP double hole Huma bunziona well ... excellent !!! Maybe my friend's problem may be due to the fact that he has a cal. 30. From Huma's indications, their TP yields the maximum in cal. 22 ... in cal. 30 is perhaps not very suitable. How many fps did you earn?

Maybe 15-20. I was expecting more. Hammer spring maxed out, 150 bar. Port on 25-30.

15/20 fps !!!!

Then they are falsehoods that I read on the Huma website. But did you do all the air passage optimization works?

However the crown is not and will never be like its impact "sister".

I did not modify the probe. Other than that there isn't much to optimize.

Reading in this forum, it seems that replacing the 5.5 mm VS with a 6, 35 mm VS also makes a little difference. Perhaps doing all 3 jobs, TP Huma or enlarging the hole of the original TP, making a double hole in the probe push the ball and changing the VS, can lead to a consistent increase in speed, which every single job cannot give.

Maybe!!!!!!

I'll not be replacing the VS.

I have since installed a hammer weight and turned the reg. up to 170. Got to 960 fps. Then the hammer spring adjuster screw stripped out! I've re-tapped the block to 6-32, but don't have a long enough screw to test it yet.

Super high power isn't going to work out for my Crown...

But there is a reason why you won't change your VS. I ask you, because I would like to change this piece, but I accept all the advice.

Is your pressure regulator the original FX one, or is it the HUMA after market one? 170 bar for the original I read that it is a pressure that cannot reach.

Having the hammer spring highly compressed pushed the hammer spring adjuster screw through the adjuster block. Those tiny super fine threads couldn't handle the pressure.

This tells me that this is the weak link in the chain. If I can't run the gun with a highly compressed spring, it won't be able to achieve higher velocities. The VS might allow for a slightly reduced spring pressure, but it's probably not worth the effort.

I'm settling for 930ish fps without the weight installed.

Is your pressure regulator the original FX one, or is it the HUMA after market one? 170 bar for the original I read that it is a pressure that cannot reach.

Click to expand...

It has an AMP reg. Max on it is 170. I have a Extra high pressure Huma reg on it's way to me, but now I know I won't be able to exploit its higher potential settings anyway. Wasted $$$...

Thanks. Very valuable information

Interesting hope you guys be successful. I could replycate it then. I'm new on this Pcp

Great news. I will try it as well

I have seen that in this USA online shop they make the modification to the brass TP in this way ... They enlarge the original hole, making it flared at the sides, and they also make a hole on the other side, as in the pellet pusher. But, in your experience, the modification of the second hole higher than the brass TP will lead to greater advantages ???