Power Tuning Mods for the FX Crown

[srtmat]

@mtnGhost

I have done the pellet probe and transfer port mods and found a nice 40fps gain in both my 380mm and 700mm barrels. Do you think putting in a larger valve seat will gain me anything?
With the current mods I’ve been running the reg down at 140bar. Got more shots and still shoots a little hotter than stock.

 

[mtnGhost]

@mtnGhost

I have done the pellet probe and transfer port mods and found a nice 40fps gain in both my 380mm and 700mm barrels. Do you think putting in a larger valve seat will gain me anything?
With the current mods I’ve been running the reg down at 140bar. Got more shots and still shoots a little hotter than stock.

Definitely. Which caliber?

 

[Runefalk]

Sorry wrong post

 

[Runefalk]

@runefalk, thanks for the reply.

One question ... is the spring that pushes your custom hammer the original one?

From what I read in the forum, I realized that I will have to get various hammers with different weights ... from 7 to 11 grams and do various tests and understand what is the weight that gives me the speed performance I am looking for. Unfortunately, Italy is now completely blocked by the virus, so it is impossible to have brass hammers built and on the web you can only buy the hammer sold on ebay, plus from the US seller .... 1 month to get it.

I'm using the stock spring. 

You can use the Fx Boss hammer weight. If I remember correctly I think it weight around 13 gram so then you can cut it to the weight you want

https://spares.bagnallandkirkwood.co.uk/product/part-a7-fx-boss-hammer-weight-17003/

 

[srtmat]

Sorry .25 cal.

And can I replace just the seat?

 

[Mask]

https://spares.bagnallandkirkwood.co.uk/product/part-a7-fx-boss-hammer-weight-17003/



https://spares.bagnallandkirkwood.co.uk/product/part-b12-fx-streamline-hammerweight-19215/



https://spares.bagnallandkirkwood.co.uk/product/fx-hammer-weight-11540/

@runefalk, looking in the UK online shop, I saw that they sell hammers for other FXairguns. In addition to the FX boss hammer, will the other hammers be okay? So you are 100% sure that the FX Boss's hammer can be used as a custom hammer for the Crown. If so, I buy two and cut the stem to different lengths, to have two hammers with 2 different weights.



I should also buy a spare spring holder,https://www.europeairguns.com/en/fabricantes-2/fx-airguns/springholdercrown

to have 2, for the 2 hammers with different weights, to be cut to different lengths. Exact?

 

[Mask]

Ahhh .... Is it better to use a brass hammer or a steel one?

 

[Long_Gun_Dallas]

I just got a piece of brass bar stock and cut my own weight. If you want to take weight off, brass is pretty soft and easy to work with. Other option is to order a heavy weight or 2 and a scale. Take some material off til you have it where you want. I only made 1 weight. 7gr for .22 was all I needed.

 

[Mask]

From what the friends of the forum write, from what I understand, for a cal. 25, you need a hammer weighing at least 9/10 grams.

I don't have the tools to make myself a hammer with brass, so the idea of ​​the edge already made in steel is interesting. I am still considering where to order the parts I need ... in theory I should order spare parts from 4 different sellers, with shipping costs that almost exceed the value of the parts ordered.

 

[Mask]

I finally started to dismantle the crown to understand how it is made and which pieces to buy. I can't disassemble the VS. I watched Ernest Rowe's video and he VS removes it with some ease with surgeon's forceps. I don't have this gripper, so I'd like to know how you managed to extract the VS. Thanks for any help.

 

[Mask]

The needle that closes the VS is the one with black Teflon, which has a size, as you can see from the photograph, of 5.97 millimeters in the metal part and 6.87 millimeters in the widest part, the black one in Teflon. My question is this ... is this needle ok if I change the 5.5mm VS and mount the 6.35mm VS titanium? Or you need to change the needle, as well as the VS.

 

[Mask]

 

[Mask]

The ORIGINAL VS that I can't get out of the Crown castle

 

[srtmat]

I would like to change mine out as well.

I saw these for sale at 910 airgun tuning.

https://910airguntuningandrepairsllc.com/collections/frontpage/products/valveseat-installation-tool-for-fx-airguns

 

[Mask]

Ahhh ... I talk to a friend, who owns an Impact cal. 30 and he told me that Huma's brass TP gave him a lot of ammunition insertion problems. He advised me to buy a TP equal to the original one and to modify it with a Dremel, enlarging the hole. Do you have experience on TP Huma?

 

[Mask]

That's fine to install the VS, but to remove the original VS, nothing is done with that pin. It takes pliers or some other tool that can enter the hole and, by force, extract the VS.

 

[Mask]

After several unsuccessful attempts, I found, where I work, in the hospital, an old hemostatic forceps and, after a few modifications with the hammer, I managed to transform it into a suitable tool to remove the 5.5mm VS. Now I order 6.35mm VS Titanium from the USA, hoping that the original needle will then seal well.

 

[srtmat]

Nice work. Can’t wait to hear how this turns out and what kind of gains you see.

I think I’ll be ordering a larger valve seat as well.

 

[Mask]

Thank you!!

By larger valve seat do you mean the 6.35mm Titanium VS?

I don't always understand English well.

 

[srtmat]

Yes I was planning on putting in the 6.35mm valve seat. I am hoping for all the airflow I can get.

With ported probe and transfer port. My 700mm Crown Continuum pushes 34gr JSB’s to 935-940fps. at 150bar. I’d like to keep the reg pressure as low as I can. I’m not planning on putting in a heavier hammer just yet. I’m just not sure if there is much to be gained with larger valve seat alone.

The valve seats are pretty cheap so at the very least it will be a fun experiment and easy to switch back to stock if I don’t like it.