new Barrel
I need a bit of advice re my new barrel, I can’t get JSB’s to group well. My 20” barrel gives me 1.5 – 2.0 cm grouping at 45 metres. When I changed to the 25” barrel the grouping went out to about 7cms?. I have tried everything to bring the group down.
1 \ cleaned the barrel
2\ changed valves
3\ Tested the grouping at various speeds ( 600 fps, 750 fps, 900, 950and 1250 fps) none of them group well. (the best group was at 600fps)
4\ removed the shroud
5\ Tried different pellets
I get 980 fps with the enjins (Blodnob valve) and they group well. What pellets do you guys use in your 25” barrel?
I am stumped. Is the twist on the 25” different to cater for the bigger pellets?
Thanx
Psion
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Viewing 10 replies - 1 through 10 (of 10 total)
it’s the same german barrel as this rifle of mine.
.20cal jsb pellets is 5.10mm… just polish the load port of the new barrel with fine sand paper. make sure the jsb skirt don’t got cought and get squeezed or damaged. then u should be ok. 🙂
guess it universal 😉 rapid freaking piece off overpriced shit…we will if DS can correct its flaws
1 burrs at the breech ,scratching the pellets
2 bad crown, not releasing at the same time all the way around, will make a pellet unstable(if shroud or mod help accuracy then bad crown is most likely the case)
3 bad barrel all together, not all barrels are created equally, some a shit from the get go and will never get better
4 but you seem to have that one covered…velocity….too high too low…
I thought for a second you were describing your Rapid…
1 burrs at the breech ,scratching the pellets
2 bad crown, not releasing at the same time all the way around, will make a pellet unstable(if shroud or mod help accuracy then bad crown is most likely the case)
3 bad barrel all together, not all barrels are created equally, some a shit from the get go and will never get better
4 but you seem to have that one covered…velocity….too high too low…
I thought for a second you were describing your Rapid…
3 possibilities
1 burrs at the breech ,scratching the pellets
2 bad crown, not releasing at the same time all the way around, will make a pellet unstable(if shroud or mod help accuracy then bad crown is most likely the case)
3 bad barrel all together, not all barrels are created equally, some a shit from the get go and will never get better
4 but you seem to have that one covered…velocity….too high too low…
Try slugging your barrel and see where the resistance in the barrel stops and ends.
Triggerman quote: “Don’t know if they make Kodiaks for the .25, but with the .22’s, they are awesome.”
Oh yeah you can get .25 31gr Kodiaks, and from what I understand, they’re just as awesome in that cal as they are in .22. More than a few here seem to like the Kodiak .25 as much or more than we like Kodiak .22’s.
Awhile back, I changed one of my guns 12″ .22 barrel out for an 18″ .22 cal barrel. I was about ready to pull my hair out for the first 150 or so shots through the barrel. It was slinging the 21.1 Kodiaks in any random 4 inch group at 50 yds. After about 175 shots I finally saw some consistency coming around.
Today, I have probably 1000 shots through it and can cover a 5 shot group at 50 yds with a quarter. I’ve never tried the JSB’s but have seen some post that they do get squirrly groups with them. I’d suggest running a couple hundred shots through the barrel before getting all frustrated with it. Don’t know if they make Kodiaks for the .25, but with the .22’s, they are awesome.
What brand of barrel is it? Have you checked the crown for burrs?
Viewing 10 replies - 1 through 10 (of 10 total)
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Thanx gents and Boondock
Polished the load port, needs a bit more work but the grouping has improved dramatically, now when my new spring arrives I am going goose hunting.