x-valve first shot chuffing

[simbad2]

need help with my x valve. on the first shoot it chuffs then fires ok
its well oiled so not that
whats the first thing to look at/try

andy

[Looper]

Two things come to mind...

Are you using the largest carrier that does not leak? (check this first)
Then, what color spring are you using, try using the next smaller spring.

[simbad2]

just try it again
when it chuff the bolt only comes out 1/3 off the way also when i shoot fast its doing the same

[Looper]

Two things come to mind...

Are you using the largest carrier that does not leak? (check this first)
Then, what color spring are you using, try using the next smaller spring.

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