Looking for tuning info for 25cal Evanix Rainstorm II

I wanted a reasonably light, affordable and powerful 25cal to have as my SHTF gun for hunting and for home protection, I looked at and thought about a 25cal Sumatra carbine but they seemed to be sold out everywhere I checked and they're also very loud. Pyramyd Air had a referbed Rainstorm II at a reasonable price with a 10% off code so I went that route. I know it's reasonably loud too but I don't believe it's as loud as the Sumatra. (maybe not quite as powerful either) I've read as many reviews as I could find about tuning it, but most of them were on the 30cal or 9mm. I haven't received the rifle yet but based on what information I could find, it looks to be much like cheap Benjamin guns with a descending shot string right out of the box. If this is true I anticipate having to cut about two coils off the hammer spring to get any kind of a shot curve and limit the extreme spread. I was wondering if anyone here has tuned a 25cal and could offer advice. Thanks Tracker
 
Tracker, send a pm to Knifemaker here or on the GTA forums. That dude has been in and out of the rainstorm so many times he’s got those things dialed in as far as tuning goes. Hammer springs, different hammer weights, barrel swaps, and also shooting slugs (store bought and home brewed slugs) you name it, he’s done it. He’s a top notch dude also.
 
I wanted a reasonably light, affordable and powerful 25cal to have as my SHTF gun for hunting and for home protection

I've always liked the way the Rainstorms looked. You might want to check the GTA forum. I know NomadicPirate (Manny) has a lot of experience with them.

In regards to using an airgun for "Home Protection", that's a whole different topic and I would suggest an actual firearm in 9mm and above. Just my opinion. 
 
Rainstorm are excellent rifles.

When the pandemia give us a brake, you can order to Huma a regulator for that rifle and you will have one of the best rifles you can buy. Accuracy and quality won't be the limit Shot count will be. The cilinder is not as big as I would like to.

My Rainstorm 3D in 25 cal with the Huma regulator is "extremely" accurate.

My Rainstorm in 30 Cal without regulator is super accurate and powerful. 

My Evanix, I have 6 ( Windy City 357, Rainstorm in 30 Cal, two Windy City in 25 Cal, one of them with an FX smooth twist Bartell, a Blizzard S10 in 22 Cal, and the Rainstorm 3D in 25 Cal) are more reliable (less leaks) than my Daystate rífles.

Evanix are "real" hunting rifles!

I have a JKHan bullpup in 25 Cal. with a Huma regulator. It is superb!!! It is a Rainstorm (almost identical) but with royal English education. 
 
My plan is to shoot it first over the chrony, if it has a declining string as I expect it will have the next step will be to try hammer spring adjustments, if still a declining sting I will clip a coil or two and test again adjusting hammer spring as needed. If the power curve is too severe and causes too much extreme spread causing poi shift at 50-75 yards I will order a Huma with the plenum for a 30 cal so air volume is not robbed by using a 25cal plenum. This is as much information as I've been able to research from the web. If anyone has anything else to add please chime in.

AS FOR HOME PROTECTION........ I do not own nor do I intend to own a firearm, with that said although the major use of this rifle has nothing to do with home protection something is better than nothing and this will be my most powerful pcp to date, this is not a criticism of the above post, just a reality of things that may come in the future unrelated to the current pandemic.
 
Hello,

I'm also in the market for a powerful smallbore air rifle. I have a few favorites for what you're 

looking for, such as the Sumatra ,25, that is a beast but not light. If you want big power for hunting

and self defense, the Airforce Escape is a single shot monster that I'm leaning towards because for 

that price, you won't find a more powerful production .25. I am also a fan of Evanix products and

as far as tuning goes, I would suggest going to SaddleMountain Airguns website, owned by Master

Tuner Will Piatt, who's specialty is tuning and enhancing all Korean made Airgun products. I called

him one day to ask some questions about a couple of modifications I was interested in getting in the future

on a few Korean Air Rifles I was interested in, and he sounded very knowledgeable on this subject. I would 

definitely reach out to him, or Veradian{?} Airguns website, a fairly new company that work on a multitude

of different products and seem to have happy customers. Best of luck.