Modifications Modern FWB Sport internals

[Kragman1]

Just a quick note for those who have one - I swapped out the OEM internals for a Vortek HW80 seal (perfect fit as received), a Titan XS #4 spring (a little shorter & slightly thinner wire diameter) and a snug fitting Delrin spring guide with the same design as the original but made to fit the Titan.
I am very pleased with this. The cocking stroke is now easier, smoooooth & silent, and the buzz is completely gone. Shot cycle seems to be just as quick. Less recoil too, yet apparently no loss of power after only 75 or so rounds of break in.
It started with a around 25fps velocity loss, but I'm now getting close to 14 fpe with 4.51mm FTT's, which is what I was getting with the heavier OEM spring and loose fitting internal components. Velocities are quickly stabilizing too, currently deviating by no more than 10 or 12 fps, down from about double that right after the swap.

I know that one option is to simply cut a coil or two from the OEM spring, but I would recommend this approach to anyone who can get a guide made up. It has transformed my Sport from a disappointment into a very impressive springer. Accuracy seems to be as good as anything I shoot, at least from what I can tell so far. Once I get used to it, it may be better than anything I shoot.

 

[Fishing 43]

Just a quick note for those who have one - I swapped out the OEM internals for a Vortek HW80 seal (perfect fit as received), a Titan XS #4 spring (a little shorter & slightly thinner wire diameter) and a snug fitting Delrin spring guide with the same design as the original but made to fit the Titan.
I am very pleased with this. The cocking stroke is now easier, smoooooth & silent, and the buzz is completely gone. Shot cycle seems to be just as quick. Less recoil too, yet apparently no loss of power after only 75 or so rounds of break in.
It started with a around 25fps velocity loss, but I'm now getting close to 14 fpe with 4.51mm FTT's, which is what I was getting with the heavier OEM spring and loose fitting internal components. Velocities are quickly stabilizing too, currently deviating by no more than 10 or 12 fps, down from about double that right after the swap.

I know that one option is to simply cut a coil or two from the OEM spring, but I would recommend this approach to anyone who can get a guide made up. It has transformed my Sport from a disappointment into a very impressive springer. Accuracy seems to be as good as anything I shoot, at least from what I can tell so far. Once I get used to it, it may be better than anything I shoot.

Where can I get a fitted guide with that spring

 

[Kragman1]

Well, I may be able to find the dims I made it to (made it up many weeks ago). The end coils of the spring were "pinched" a little, so I did open one end coil to match the true ID of the spring. You may not need to, it depends on your spring.

Give me a little time to dig this stuff out and I'll post it here. Glad to give details and help out. I'll be able to post dimensions for a spring guide that works with an OEM spring as well - one of those and a Vortek HW80 seal should also do wonders for a Sport.
And, sans the ability to make a custom guide, even a soda bottle sleeve over the factory guide would be great.

 

[Kragman1]

Just a mini update - I did get it to the range today, but in very gusty and swirly wind so not much for groups to show. But I now have around 150 rounds through it (guesstimate) and I ran it.over the chrono when I got home.
Velocity with the Titan #4/Vortek HW80 seal is at least what it was with the OEM spring & seal, cocking is easier and when I did get a small break in the wind the rifle shot very impressively.

Numbers:


That's right around 14 fpe for the tight-ish R10's and 14.7 fpe for the easy fitting JSB 8.44's. The Superdomes were too tight really, and it shows in their relatively low velocity.

I don't know when the seal will be done sizing itself. It could be done now for all I know. But wherever the numbers end up, I am more than happy. I expected to lose some velocity with the shorter/fewer coils spring. But it looks like I'm keeping it all and not sacrificing accuracy. Win/Win in my book.

 

[Kragman1]

Fishing 43 - I didn't find my own notes, but I'll look harder. If I don't find them, I can recreate the numbers. Just give me a little time.

 

[Fishing 43]

Fishing 43 - I didn't find my own notes, but I'll look harder. If I don't find them, I can recreate the numbers. Just give me a little time.

Thanks I appreciate your time and effort.

 

[Kragman1]

FYI all - like I said, I did get it to the range yesterday, and it was in my hands during the best lull of the afternoon, so I made haste to try to get a good sight in.
The descending shots were from vertical scope adjustments, just trying to get to the 1" sticker. Then a bunch of shots trying to make a group before I lost the wind. Then a slight W&E adjustment and fired the last shot (nearly centered) during another lull.

Amazed by the small group in poor circumstances. There is one shot outside the group I measured, but I figure that was either me or the wind and I chose to leave it out.

Two other owners moved on from this rifle before it came to me. I'm really excited to see what it may become after a simple tune.