TX200 Short Stroke

[cooper_dan]

Finished my TX200 Short Stroke (80mm) yesterday, and finished writing it up today.
Using standard Mk2 spring and guides, makes 10.8 ft-lb with zero power washers

Shoots better than I thought it would, a better shot than me could one hole group with this gun I'm sure of it

http:///tx200-sho...oke-conversion

[PhatMan]

Dan,

Excellent stuff, and nice article

My TX200 has gone to an even shorter stroke - 70 mm.

Mr. Price (Wonky Donky) did the work, and it shoots sublimely.

Power was originally set at my request to 10.5 ft.lb, but I now have it set at 10.0 ft.lb for some experiments that I am doing.

(lots of chappies on the Forums bemoaning that their rifles 'only' make 10 ft.lb as if it was the end of the world. I thought I would run the TX200 at 10 ft.lb for a year and see what was really what WRT that energy)

10 ft.lb gives me ca. 760 fps with JSB Express (7.87 gr.), which is the most accurate pellet in my TX.

Trajectory over 55 yards is not much different from 10.5 ft.lb (or even 11, or 11.5 ft.lb).

So far, I have not found any downside to running at 10 ft.lb

Have fun & a good Sunday

Best regards

Russ

[cooper_dan]

Thanks Russ,

10.7 is about right for me. Thats JSB exact 8.44 at 755 fps.
I think there is a lot to be said for finding the speed at which your pellet works best, not just the power it can achieve. I was watching one of the Teds Holdover videos on youtube recently, and he found that adjusting pellet velocity made a huge difference.
I've spoken to people who run high power who didn't like express pellets (820 fps = 11.75 ft-lb). Maybe there is a magic number between 750 and 800 that is perfect for soft lead pellets.....

Easier to test on PCP's is you can get to the power adjuster/regulator. Springer would need some thin washers. Maybe 1/2 or 1/4 mm ones to fine tune the pellet speed. Luckily the TX is so easy to strip this is actually a feasible test.

Thinking more down these lines, it is well known that every barrel likes different pellets. And in FT and HFT it is well known that different die numbers of the same pellet make a difference. Maybe each die number would work best at a different pellet speed too. So you could find maybe the three best pellets. Then test each of them at varying power levels to really narrow down the best combination of die number and velocity you would be on to a winner. The obvious downside is that this is a huge investment in time and not many people are likely to be able to, or want to do this.

I've put it on the list for a future test. I've got a TX200HC 'garden gun' running at 9.5 ft-lb at the moment. If I can find thin enough washers I could do this test next year

[PhatMan]

Dan,

Ta

Looking forward to more on your blog

Have fun & a good Sunday

Best regards

Russ