Changing The Evanix REX Barrel?

I have the Rex rifle, and have converted it to several different calibers...i made my own barrels, and there is some machining required...I had to make new spacers and different hammers to get the performance I wanted...also spring changes
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 The different barrel od’s I had on hand required lotsa work to get them fitted,,I have a 177,22 308, and 45 and an arrow barrel...but I also have a pile of springs, hammers,spacers to go with it...it’s an unregulated hammer
 
Hi 17Hornet,

It looks like you're really into the Rex. Thanks for the great reply. In changing calibers, did you need to modify the valve to accommodate the difference in bore diameters? I have a lathe and do hobby gunsmithing, so machining isn't a problem. Did you use an air gun barrel or a centerfire barrel for your .308 project?

Thanks, Howard 
 
I did not modify the valve itself, but had to make a top hat to fit over the existing top hat, to accommodate the larger barrel in 45...so that meant I needed a new hammer with a larger bore for the 45 barrel...plus hammers and spacer...it was all a big experiment...

the buttstock reservoir in the picture is one I made to accommodate the sliding ar style buttstock.that uses a valve I made to fit it. The 308 barrel is a firearms barrel, the 45 and 25 barrel are air rifle barrels

fun project...have fun!
 
Hi 17Hornet,

I haven't seen much information posted on the Rex air guns , so please excuse my many questions. What can you tell us about accuracy and velocity you see with the .308 barrel? Are you shooting slugs or pellets? A couple of years ago I built a talon style rifle in .45 cal., using a 1:48" twist muzzleloader barrel (my first PCP). This haywire lashup uses a Mag Lite flashlight for the receiver and a paintball tank, with home built valve. It's kinda crude looking, but shoots. Maybe I'll post some pics .

Cheers, Howard 


 
My 308 is a 1in 10 twist.. it was a new blank I had lying around...I am able to get around 1/2” at 50 yds with the heavy jsb’s. At 100,it’s about 1-1/4...I think the barrel is doing fine, but unregulated accuracy at distance on the Rex is kinda iffy, I’ve been using different springs, trying for a little lower velocity for more shots. 650fps seems to be the best for accuracy right now.... It’s a really inefficient rifle....but fun...
 
I also have a .25 and 9mm Rex . Both fitted with lothar barrels . There’s a lot involved to swap out barrels . Lathe work for hammer , threading , machining the pellet loading tray area . I’ve also built dozens of valve combinations for both calibers . Can definitely say the lothar barel upgrade added power and tack driver accuracy. Especially the .25 . Special consideration of space between valve and end of loading tray area and relationship of valve open and full travel of hammer. Once you’ve scratched your head a few times on the way they function , huge power can be made from these beasts . My 9mm is hurtling 115 grain cast hollow points at about 1050fps with out problems . About 5 full power shots non tethered . 
 
WOW, 1050 fps sounds great Furmaha! I modified a 158 grain SWC mold to throw a 103 grain bullet for my 9mm. It seems to work well, but needs some serious bench shooting to prove it out. I'M currently machining a .22 c.f. barrel blank to try out on my Rex pistol . It'll be 14 inches long when finished. I'm hoping it will shoot .224 dia cast slugs. Do any of you guys have any advice on valve or spring mods?

Thanks all.