FX Impact MK II .357 barrel tension to help with harmonics and barrel droop

Hello I have been working on this project for about 3 weeks now. I watched Ernest's videos on how to put your barrel under tension to help with barrel droop and harmonics. I purchased the 14mm x 20mm 3k carbon fiber tube that he used in video and cut it leaving about 1mm longer on the length but then I was stuck trying to figure out the size and thread of the liner lock witch after talking to FX USA it's a 13mm x .5 pitch on the threads witch is micro threads. I hunted down a tap from McFaddendale hardware witch was special order and $25.00 but then I was in a position that I also wanted to be able to use my moderator so I needed 18x1 threads to put moderator on so things were getting more complicated so reevaluated the situation and came up with this. I took old .357 shroud and went to my buddies shop where we chucked up the original shroud and bored the cone out to 20mm to allow the 14mmx 20mm carbon tube to slide onto the barrel leaving about 1 mm longer then barrel length and laving the 13 x .5 treads from the liner lock exposed so now I slid shroud over the 14x 20 carbon fiber tube that is full length of barrel and the shrouds now can screw back onto the liner lock and tension the barrel. I will get some pictures of what it looks like in a couple of hours.
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I did a barrel tension mod a while back but did it the easy way.

https://www.airgunnation.com/topic/finished-up-on-my-impact-barrel-tension-mod/

I did it this way until I got all of the parts together to do the above. The Delrin piece as just a tiny bit longer than the space between the barrel shroud and the barrel guiding block at the rear. So when the shroud is tightened up it tensions the barrel. I was quite surprised at how much droop this took out of the barrel and how much more stable it was.






 
I was shooting mostly sub MOA at 100 yards before I did the mod so they shoot fine without it. This did not improve my accuracy. Although it may have helped with POI shifts I used to get every now and then. I just like the fact that there is no longer much droop in the barrel and it is so much more secure than the way it comes from the factory. I also replaced the four NBR 70 o-rings that hold the barrel with NBR 90.

Many if not most of the airguns out today could do with a bit more stable barrel.
 
The 14mm x 20 mm is the outer barrel carbon fiber tube i ordered 2 36in 3mm thick carbon fiber tubes off of Amazon they shipped out of china had them in 3 days. Amazon link for carbon tube. https://smile.amazon.com/gp/product/B0798MDN9J/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1  . The inner carbon tube that goes around barrel sleeve i got from Utah airguns. Here is the link. https://utahairguns.com/fx-carbon-fiber-liner-sleeve/. The shroud showen above just has a cabon fiber vinal wrap on it.