B40 Barrel and shroud removal
B40 havent been as accurate as i wanted….could be that i cant shoot springer for shit or it could be the rifle.
i decided to take the plunge since i didnt get any better today after trying several things….the shroud and barrel has to come off
reading the net, i find that this is a paint cause of the brow epoxy used by the chinese….i found the post where he suggest to heat the base, and i think hmm its just glued in the base….WRONG.
the shroud only goes in the base of the rifle about 1mm, the glue that need to be heated to be able to pull the damn shroud off runs the lenght of the entire barrel GRRRRR so after a lot of useless heating at the base i decided to get violent, and it finally starts moving, i got the tip of the shroud in the mill vise. i actually manage about 5″ before i need to add some more heat…..after 15-30 minutes (i loose track of time) it finally comes off, what a bitch that was to get off….
if you wanna remove it….heat the entire shroud minus4 inches at the front…..and start twisting it, you can tighten it down in the vise pretty hard as the shroud is very thick walled, and the vise will be clamping down on the endcap which is also pretty thick, so i think it will be hard to crush the tube.
i do advise setting up a fan to keep the awefull epoxy fumes that will be smoking from the rifle when you heat it up, away from your face
Barrel is left with some scratches from the removal of the shroud….it is press fittet, but only about 5mm or so rest is glue, and the nut that sits inside the reciever…grab your 17mm bit and try unscrew it…if it wont heat it for 10 secs with a gas flame and you should be good to go…untigten it, so it just has 2 revolutions before it come off….
start heating the barrel base and the rifle body, keep the flame on the barrel to avoid damaging the bluing, mine changed color a bit 🙁 heating the barrel only should heat the body from the inside, but will take a bit longer than just torching it all, clamp it in a vise again….heat and try twisting the body….keep heating till the glue lets go…i used a pair of screwdrivers one through the cocking arm linkage hole, andone through the scopestop hole, it will require quite a bit of force (alot actually)
the first ½” i couldnt twist it all so i took a roundstock of aluminium and dumped through the pody so it was sticking out the back and started hammering, be carefull to use something softer than the barrel…aluminium.
once the press fit was passed i could start to twist it loose, keeping the heat on the barrel once every 2-3 minutes….and it finally came out YAY
all in all about 1 hour used
wonder hot it all is going to fit together again, if glue is needed or the nut will be able to hold it in place.,,,it was too hot to mess with when i quit
i considered getting a 16mm barrel and thread it at the base and then thread the rifle body as well
well gotta recrown the sucker first , and get that real nice…might shorten it, and sckip the barrel all together, anyone know how long the TX200 HC barrel is ?
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GRRRRRRRRR
rifle has been put together quick when i shot the groups above….no loctite or anything….it was shooting well so i decided to finish the rifle
i pulled the shroud off only to see rust marks on the crown….wtf…crown had gotten full milltech treatment…i think the rist came from the insiede of the shroud, there might have been some moisture in there from when i shot pellets into a bucket of water to see how they looked…i use a lid to shoot through to limit splash…but it must have gotten in there
ok i push a pellet into the muzzle head first ever so gently, and with some light polish get the rust off…give the shroud a spray of wd40 and run a brush up and down to coat it all….barrel gets a liberal amount of oil on it….and crown gets another milltech oil treatment (heating it up 3 times etc…)
spring is removed as i have gotten some tar for it and i want to give it that….a medium coating…just enough to pull string of it between coils when you run your finger over it….thats how i was told to do it….about to put it all together and i notice the front spring guide on the floor….hmm did that just fall out today or was it missing all the time ? i clean it up and give it a light moly coating
i reassemble everything with blue locktite, give the shroud a dab of crazy glue, and let it all sit for 30 minutes.
the i go to shoot it….its off a bit…but thats ok….then it starts to shoot 1″ groups at 10 yards !!!
its back to its old self !! GRRRRRRRRR well a little better but not much
crown looks perfect, its smooth cocking, lowest vibrations ever recorded with that rifle….everything is as it should be….except it wont group any more !
can it be the front springguide adds too much preload to the spring, and thats why its not grouping…is it because the front guide adds more power that its not grouping….
everything else is about the same….
thanks i will try and get it off then
Here is mine without barrel sleeve. It has now German made Haenel 300 series barrel (NOS parts) and it’s lightyear ahead original. Sorry some poor pics.
http://s246.photobucket.com/albums/gg101/Tunajussi/Bam%20B40%20177%20cal/?albumview=slideshow
Cocking arms muzzle end plug is threaded (mine wasn’t glued) and I think they use this construction both end. Apply some heat and twist.
TX200HC barrel length: 242mm – overtube 320mm
http://www.air-arms.co.uk/TXANDHUNTERCARBINE.htm
i was gonna give it the benefit of the doubt and cut it a new crown…had that not worked i would have sold it….
but its much better now….so im gonna go ahead and tune it with some tar and moly…thread the shroud for some small setscrews so it wont be hard to take that off
was thinking of shortening the shroud, to save some weight or replace shroud with carbon tube, as it weighs a ton…does anyone know how the cocking handle is attached ? i think its glued in place the rest of the rifle is.
i managed to shoot some more yesterday, and i tightened 5 shots groups to ragged oneholes when i do my part, it is now up to me to be accurate and not the rifle….it doesnt mind being held tight anymore, or rested…it does mind here the shoulder is placed but otherwise it just shoots now…
might get the dremmel going….and checker the handle and forearm…might even go nuts, and mill the stock like one of them falcon skeleton rifles….still thinking about that one
might be a “keeper” gun after all. Nice improvement.
second try
2 groups of 5 shots
lower one i pulled 1 shot so i added one
i could have polished it up to perfection, but decided chinese is chinese and this would have to do…picture makes my crown look more rough than it is
but the results are amazing !
before trying my best at 16 yards
after i tried the same…it was shooting high so i lowered it a bit…yet still got this group
i dont think it was as hold sensitive as i thought i was…now it just shoots !, was the crown and breech all along
Nice job. Damn, that old crown was rough 😯
That’s a good looking crown 😀
Looks like it would shoot rb good too.
got a bit more done today, man was my hands and fingers aicking from yesterday….realized i hat gotten some cuts…anyhow
the original crown was slightly offset, hard to see but once spining in lathe it was clear as day, so it ripped it a new one…
then pushed a pellet through and i couldnt understand there was scratches, turns out the breech was nipping the pellet as it went in, so it got 10 secs spinning max in lathe with some sandpaper in there, that took care of that
noticed the pellet wouldnt seat all the way in but have about .005″ sticking out, so in chamfered the breec a bit, and now its flush
pushed another pellet through and it came out nice, but the rifling is real shallow allmost non exciting, shooting into water and the skirt has a bit more rifling to show, guess the pressure flares out the skirt more than when just pushed through, and pellet was nice and uniform in the riflingmarks.
so rifle went back together….and it shoots one holers at 10 yards, gotta wait till tomorrow and see if its gotten better at 16 yards
if its better, it will be torn back down and get shroud glued in place, i whish there was a way to avoid the shroud, it does practially nothing to the noise, and just adds weight and lenght, which i dont need.
i might cut a ring out of the shroud, and use it to to get the cocking arm holder in place on the barrel, and then shorten the cocking arm a bit to fit, make a hunter carbine out of it.
here some pictures
before
after
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turns out it just needed 50 shots through it after assembly and it got nice and accurate again….however…never again a chinese springer ! too much trouble, when you can have a rws34