FX Wildcat MK3 Comp BT tune

I have a 22 cal Wildcat MK3 Compact BT. It was set up fairly well from the factory, but I wanted to bump up the power a bit but still be able to shoot pellets and slugs without sacrificing much shot count. I found that the OEM hammer weight was 11.50 grams. I had some other weights from a factory tuning kit and a power kit weighing 12.96, 14.3 and 26.1 grams (see picture). I installed the 12.96 weight and I can keep the reg at 90-100. It shoot 18,3 gr up to 940 and 25.4 at 840 fps. What hammer weights have you guys used?

Weights L to R: 11.50 (OEM steel), 12.96, 14.30(brass) and 26.1 grams (tungsten?)
Hammer weights.jpg
 
The 11 gram weight is actually for the .25. I am very surprised that your Wildcat is working right with the heavier hammer weight and that low of a pressure. Does your adjustment wheel work correctly or is it reversed?
The 11.5g weight is what came in the gun. According to the FX parts list, there is only one hammer weight for all guns and is not caliber specific. The power wheel seems to be working ok, but numbers 5,6, and 7 give me the same velocity, then it drops off at 4,3,2, and 1.
 
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Their schematics does not list the full range of those weights. Typically it is a 7g for .22 11g for .25 and 13g for .30 I always ordered the 11g version for my guns as it was the best one for a pretty full range of pellets and slugs....unless trying to really push heavy slugs. the heavier the weight the higher the pressure you are going to need to really match to get things really working in harmony. You can dial your adjustment screw in to compensate, but that does have a limited amount of travel.
 
I just installed a new hammer in my WC3bt also in .22. It looked like the copper colored one on the far right in your picture. I didn’t weigh it before installing (oversight on my part), but it came with the pin probe in the FX slug kit I ordered. I haven’t started adjusting the regs yet, only had time to install yesterday. What settings are you all using on your regs with the different hammer weights? I am hoping to get mine set up for lighter slugs (18-23gr) and heavier pellets without needing a slug liner.
 
I just installed a new hammer in my WC3bt also in .22. It looked like the copper colored one on the far right in your picture. I didn’t weigh it before installing (oversight on my part), but it came with the pin probe in the FX slug kit I ordered. I haven’t started adjusting the regs yet, only had time to install yesterday. What settings are you all using on your regs with the different hammer weights? I am hoping to get mine set up for lighter slugs (18-23gr) and heavier pellets without needing a slug liner.
That's the heaviest one-26 gm. I used the second from the left at 12.5 gm. The OEM part was 11.5 gm. Right now, I've backed off from the high power and will shoot 18.1 gr pellets for the most part. My reg is set at 95 and with the hammer set at #7, it shoots them at 927 fps. I works quite well with 20.2 gr NSA slugs at 868 fps. If you want more power, then jack up the reg pressure, but you will lose shot count. I'm getting 60 shots per fill. I wouldn't go higher than 110. Setting the adjustment screw on the hammer will throw a lot of that out the window. I tried screwing it out to max as Ernest Rowe did on this video
but this wastes a lot of air. I adusted the screw like this video and it's perfect.

The NSA 20.2 slugs (.217 dia) shoot fairly well. FX Hybrids and NSA 23 gr? Meh! This gun will shoot the JSB 25.4 gr pellets pretty well, but you will have to push the power to get the speed of these up to around 880. I have no intention of buying a slug barrel, because I really don't care for slugs. Ted Bier adjusted his Wildcat BT Compact to shoot 23 gr NSA really well, but that's all it will shoot and shot count is about 1 magazine I figure.
 
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That's the heaviest one-26 gm. I used the second from the left at 12.5 gm. The OEM part was 11.5 gm. Right now, I've backed off from the high power and will shoot 18.1 gr pellets for the most part. My reg is set at 95 and with the hammer set at #7, it shoots them at 927 fps. I works quite well with 20.2 gr NSA slugs at 868 fps. If you want more power, then jack up the reg pressure, but you will lose shot count. I'm getting 60 shots per fill. I wouldn't go higher than 110. Setting the adjustment screw on the hammer will throw a lot of that out the window. I tried screwing it out to max as Ernest Rowe did on this video
but this wastes a lot of air. I adusted the screw like this video and it's perfect.

The NSA 20.2 slugs (.217 dia) shoot fairly well. FX Hybrids and NSA 23 gr? Meh! This gun will shoot the JSB 25.4 gr pellets pretty well, but you will have to push the power to get the speed of these up to around 880. I have no intention of buying a slug barrel, because I really don't care for slugs. Ted Bier adjusted his Wildcat BT Compact to shoot 23 gr NSA really well, but that's all it will shoot and shot count is about 1 magazine I figure.
Thanks for the input and the videos. Appreciate it.
 
I just installed a new hammer in my WC3bt also in .22. It looked like the copper colored one on the far right in your picture. I didn’t weigh it before installing (oversight on my part), but it came with the pin probe in the FX slug kit I ordered. I haven’t started adjusting the regs yet, only had time to install yesterday. What settings are you all using on your regs with the different hammer weights? I am hoping to get mine set up for lighter slugs (18-23gr) and heavier pellets without needing a slug liner.
I've got the same gun and caliber. I had to install the slug kit to get the speeds I was after. My regs are 175/135 I tried most all .22 slugs and the nsa .218 in 20.2gr shot the best @970fps.
 
I've got the same gun and caliber. I had to install the slug kit to get the speeds I was after. My regs are 175/135 I tried most all .22 slugs and the nsa .218 in 20.2gr shot the best @970fps.
I'm using 0.217 slugs. The same as Ted Bier in his Teds Holdover video on Youtube. A tighter slug will slow down velocity.
 
The 11.5g weight is what came in the gun. According to the FX parts list, there is only one hammer weight for all guns and is not caliber specific. The power wheel seems to be working ok, but numbers 5,6, and 7 give me the same velocity, then it drops off at 4,3,2, and 1.
There are multiple factory hammer weights available depending on what Cal and when it was made. Sometimes FX mixes them up and sells a new rifle with the "incorrect" weight. So your reg setting being on the low side of the scale, one of the lighter versions would likely be the best valve/hammer balance. There are also two different size springs, and customers/FX mix and match different weights depending on desired performance. There is a 52mm and a 56mm spring.