Diana Diana 54 air king pro 7.5J

I have a 7.5 J coming and I’d like to see if anyone has ever converted one to full power. From the very little information out there about the low power versions it looks like there’s more than likely a transfer port restriction in the form of a washer with a tiny hole ( 2mm or less) as an air passage and more than likely a weak spring in there. I’d like to hear first hand from someone that has gone down this road before.
I did send Hector an email asking about a short stroke piston but he didn’t seem certain as Diana uses all kinds of different methods to detune their rifles.
I have a Maccari spring , piston and breech seal coming from ARH and hoping I’m not missing anything.
I’d really like to get this rifle shooting close to 20 FPE as long as it likes the 10.3 JSB pellets.
This one came up on sale , brand new for 550$ snow pesos ( canadian dollar ) which I thought was a very good deal, considering there are some vendors still asking 1100$ for exact same rifle. So even after the extra parts and a bit of time I think I’m still way ahead ( if that even makes sense)


I was supposed to be downsizing my collection. Throw that plan right out the window. 😂
 
I have a 7.5 J coming and I’d like to see if anyone has ever converted one to full power. From the very little information out there about the low power versions it looks like there’s more than likely a transfer port restriction in the form of a washer with a tiny hole ( 2mm or less) as an air passage and more than likely a weak spring in there. I’d like to hear first hand from someone that has gone down this road before.
I did send Hector an email asking about a short stroke piston but he didn’t seem certain as Diana uses all kinds of different methods to detune their rifles.
I have a Maccari spring , piston and breech seal coming from ARH and hoping I’m not missing anything.
I’d really like to get this rifle shooting close to 20 FPE as long as it likes the 10.3 JSB pellets.
This one came up on sale , brand new for 550$ snow pesos ( canadian dollar ) which I thought was a very good deal, considering there are some vendors still asking 1100$ for exact same rifle. So even after the extra parts and a bit of time I think I’m still way ahead ( if that even makes sense)


I was supposed to be downsizing my collection. Throw that plan right out the window. 😂
While your at it call Hector back and get a tuner from him. It cut my groups from a tuned 54 in half and that's with 15.89 JSB at 760 fps.
 
While your at it call Hector back and get a tuner from him. It cut my groups from a tuned 54 in half and that's with 15.89 JSB at 760 fps.
I’ll be calling him once I get the rifle tore down and take some measurements. I do have a couple air strippers from different suppliers , and they do improve groups a bit. Knifemaker ( who I haven’t heard of in a few years ) and I worked on some vibration dampeners a while back. I still use them on a couple of my high power slug shooters. Think dead blow hammer.
 
he drives me nut as a presenter, but he does have some interesting products
the idea that you could respring a 48-52-54 to full power and not need a spring compressor is an appealing idea
i made a comment on a UK forum about using a magnetic dish for the parts, he tends to scatter them around and i was watching a video and he made an effort to point out he got one and was using it

good luck with your rebuild
mike
 
he drives me nut as a presenter, but he does have some interesting products
the idea that you could respring a 48-52-54 to full power and not need a spring compressor is an appealing idea
i made a comment on a UK forum about using a magnetic dish for the parts, he tends to scatter them around and i was watching a video and he made an effort to point out he got one and was using it

good luck with your rebuild
mike
One of his spring guides gave way on my HW80 Wouldn't use his kits
 
he drives me nut as a presenter, but he does have some interesting products
the idea that you could respring a 48-52-54 to full power and not need a spring compressor is an appealing idea
i made a comment on a UK forum about using a magnetic dish for the parts, he tends to scatter them around and i was watching a video and he made an effort to point out he got one and was using it

good luck with your rebuild
mike
That’s funny. Many years of racing slots and RC cars taught me to use those. I also have a mat, kind of like a large mouse pad, that’s very handy.
 
small parts disappear we have all lost something an spent 30 minutes looking and then find it and wonder how the hell did it get over there and many of these parts are not available and if they are, will cost you 10 bucks to replace
i just fixed 5 Ruger MK ll because they would not cock and i use stick magnets for the small parts
no matter how hard you try you will lose a part