Fx crown .25 cal tuning question

Hello folks,

I was watching a video from meathead Marksman in YouTube where he tunes his 25 cal crown.

He didn't push upto 900fps with 33.9 grain jsbs but in a comment he mentions that 900 fps are achievable if you set the regulator at 150 bar or a little bit more. 

I was wondering... What are the max fps/fpe that you have gained from a tune?

I just got a chrony today and wanna see how close to 900fps i can get. I have a stock fx crown. 25 cal with 33.9 heavy kings mk1. 
 
In my .25 cal. Crown, I have the simple 2018 Power tune kit from Ernest Rowe - FX and can reach 1000fps with the 25.4gr. JSB's and 885fps with the 33.95gr.JSB MkI's. My regulator is set a little above 150BAR, somewhere in the 153-154BAR range. The kit gained me about 30-35fps but that can vary depending on gun. If you are willing to buy the 2019 power tune kit from FX, which is a lot more comprehensive, power increases should be more substantial.

My chrono readings without the power tune kit, my reg. pressure set at 150BAR and my hammer spring tuned for maximum velocity were a little higher than most of the other results I've heard of from other Crown owners but there have been a couple of posts I've read where Crown owners had even higher velocities. I couldn't reach 900fps with the 33.95 JSB's but it might be possible.

One other thing... I've read many times that turning the reg. pressure past 150BAR can be bad for your gun or not advantageous without rearranging the Belleville washers. I've been told by two of the top people at FX that this simply isn't true. I really don't know who to believe or if it's true or not. I can tell you though, I've had my gun adjusted as high as about 158BAR for a while and then set at 154BAR where it's currently set and has been for a while without any problems. I have a slug liner coming any day and if it's necessary to turn my reg. pressure up, I won't worry about it one bit.

Keep in mind that velocity is nothing without accuracy. I too have tried to achieve 900fps with the 33.95's because when I install my slug liner I'm going to be shooting some heavier slugs and am hoping they'll shoot well at higher velocities. If they don't, I'll either shoot a lighter slug or turn the reg pressure down a bit. For me accuracy comes first, velocity/energy second. Good luck!

Oh, one other thing, the gauges on these guns from the factory aren't the most accurate, but these numbers I've quoted are the numbers my gun shows. I hope this helps a little.

Stoti
 
Cool, glad I could help! I don't know if they're out yet, how much or if Ernest has to install them. I think so though. That was the original plan. I just decided to stick with the 2018 kit for the time being, at least until I test the slug liner that'll be here tomorrow and see if my power is sufficient. When you go to tune your gun, start by adjusting your external adjustments, the Hammer spring and the regulator and then go from there and decide if you want to go with the full blown power tune kit. Make sure you take good notes...where your settings were when you started, everywhere along the way and where you ended up. It's easiest to measure your hammer spring tension with a micrometer so things are accurate. Bob O. has a video on AGN showing exactly how to do it. Good luck!

Stoti
 
Around 55-60. Probably closer to 55. Heck, might be less, I'm not 100% sure because I usually refill before I get down to 154BAR and haven't really been watching closely. I plan on shooting a bunch tomorrow, I'll let you know for sure. One other thing worth mentioning, I found out last week that this gun has the AMP regulator according to the serial number, even though I purchased in last July. Don't know if that has anything to do with anything but I thought I'd mention it.

Stoti 
 
Hello Skipp,

I wanna buy the power kit and if it doesn't come with the kit, the weight as well. This is the first time I hear about that... for example Meathead Marksman doesn't mention that mod at all as his crown was bone stock, at least at the time of the tuning video he made.

How can I purchase them? Do I have to call FX USA? Or how can I contact Ernest Rowe?