Raptor gets an upgrade

Captain's Log, Stardate 20200512

I removed 2" from the barrel as planned. Re-threaded on my lathe, and I started rummaging through odds and ends to cobble together a shroud to tension the barrel as a stop gap.

Well, I found that using the JSAR tensioner with a tapered end cap from an old 600mm FX Crown barrel kit, and a 500mm FX Dreamline seems to work pretty damn well, despite being an ugly Frankenstein setup  

That’s not ugly...that’s sheer genius on your part! And, it WORKS . Nice work.

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Thanks! Hoping that JSAR will sell me a tube for their 24" Raptors, but something like this should get me by for a bit lol

Too late to drive out to test it at paper today - but MAN, it's still SMOKING with power! When I got this rifle, the reg was set to 2050-2100psi and shot the 44.75gr JSBs at 888fps. With this 24" barrel, I had to turn the reg down to 1800psi, giving me 890fps.

Unfortunately, it isn't quiet. There's an air stripper built into the Dreamline shroud, and I have a Ronin on the end. Not enough to make it backyard friendly! I need that longer JSAR tube to tame the noise

Dang! A whole lotta power with the longer barrel at that reg pressure! You definitely need the longer tube! Luv what you’re doing with yours

. Enjoy following your thread....fun stuff! Friend just purchased a Crown Continuum and difference in speed between the 380 barrel and 700 is 100fps’

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Get you some hammer weight higher VDT! I got around +200fps with Monsters in mine.

Speaking of dwell, when I opened thr buffer - I saw the target velocity that I was looking for with the 26" (vs 17") to be confident enough in cutting it down to 24". I might even consider 21-22" if this length bugs me in the field, but right now the length seems completely manageable.

This little Dreamline shroud is NICE with the built in air stripper. If it shoots well, I might just wind up getting one in 600mm and call it good!

Started my next mod nonetheless. Removed a few mm off the FX endcap and cut an external o-ring groove to dampen everything better..




Fits like a tight glove  

Really cool build Mtn!

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Thank you sir.. Still have a ways to go, but I'm hoping to get'r all dialed in soon!

Kicks like a mule when the power is cranked up .. first time I've had to be mindful of eye relief with an airgun, luckily the SideShots have that rubber piece in the end!  

Good work my friend, why didn´t you make an adaptor instead of working the barrel direct? that way you can use it in any AG .30

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It wouldn't have been worth it. The barrel OD is 0.551" seats in the block 3.75" and has to be turned down to 0.5" to fit for that length. The probe can't be any longer than it is (only goes in ~0.55").

Well JSAR would not sell me a shroud tube for my Mini, so I was in my own to setup a proper shroud for my 24" barrel. I went with a 20.5" 6061 aluminum tube, had to do some work to it to receive the Raptor air stripper / threaded barrel tensioner thing for the muzzle.

I also spun the JSAR part on my lathe, and cut out a larger groove for a fatter o-ring (which compresses against the inside of the shroud tube). The o-ring they were using was real thin and I felt that it could be improved, but I can run a 15 x 3.5mm in there now.

My groups had tightened up when I was out a couple of days ago. i was running my reg at 1800 with 44.75gr JSBs, using the Frankenstein FX Dreamline shroud system. I'm banking on tighter groups with more shroud volume and much better barrel tensioning with this bigger tube:

 

Nice! If you wanted to save some weight you could get something from..Clearwater Composites.

https://www.clearwatercomposites.com/products/carbon-fiber-tubes/colored-tubing-round/

If your Raptor grip and stock were an OD green, the Texalium color would probably go really nice..or in today's parlance..sick!

https://www.clearwatercomposites.com/products/carbon-fiber-tubes/round/std-mod-round/?filter_nominal-id-range=0-500-0-999

Standard dark gray carbon would go with what you've got.

You'd just need a hi-speed carbon fiber cut-off wheel to make the cut smooth without splinters..an arrow cut-off saw would work.

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Thanks. I couldn't run CF tubing for a shroud on a hunting rifle like this. I've worked with carbon fiber tubing before, and I'm just not a fan of the material. This tube is pretty light though. I plan in adding an aluminum air cylinder next, mounting a small M-LOK rail, and adding a tensionable barrel band system that I devised In my mind for it.

Unfortunate you couldn't get part support from Jsar, I'd imagine for the average Joe that cannot machine/fabricate their own would be a bit upset having to outsource this job elsewhere. I fear they'll go the way Wicked Air Rifles did if they don't turn things around...



Great work nonetheless. I would personally keep the aluminum shroud on over carbon fiber..being 30 cal and seeing quite high pressures, carbon fiber threads would have to be re-enforced to withstand it all over the course of its life..IMO.



The rifle is begging for a paintjob/hydro dip to match the stock! Would look pretty slick in dessert sand or some kind of green.

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Yeah, the entire reason that I started to do this 24" barrel project was to have an accurate barrel on this rifle since the 17" had a defect. I bought the blank from TJ's long ago, did all of the work myself, thought I could help out JSAR by purchasing a shroud and save myself a few hours cleaning up and painting one on my own.

That said, I've been thinking about hydro-dipping the rifle in Multicam or powder coating the shroud in tan. For now, I'm just going to leave the shroud in a 600-grit satin finish. I still need to test and tune this thing to see if it can handle big slugs accurately at high power like I planned. About to go full Jedi on this thing and figure that out.

Very nice shroud and machining to get it tensioned properly with larger threads and o’ring! The hydroo dip would look marvelous! Definitely go full Jedi on this beast! I think only Jacob and one other person is holding down the fort, covid related...reason why they cannot take on other projects. That’s some serious power using a 1800 psi reg settling on a .30! These balance valves open so easily...my HS is backed almost completely out with reg @ 1600, easy quiet power in .22. Cannot wait to see your project complete! Luv these TJ. barrels! Keep up the awesome work!

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Thanks dude! I had my rifle pushing 65.5gr ammo at 140FPE with the 26" barrel at just under 3K PSI. My goal is to run it as low as possible, but I need it to push heavy lead. Ideally, no more than 200bar (which still gives me a decent shot count for hunting believe it or not), but ~160-170bar seems to move the 60+ grainers at the velocities that I need.

BOTH times that I had this rifle out to test, I forgot to bring my 50gr JSBs I definitely want to see how they do with this rifle while I have it tuned low.