disco accuracy and power issues,any advise/ideas.

[one_shot]

if the brake is causing the issue id suggest a tko 6.5, plenty of people use those with any issues with groups opening up

i dont think the brake is causing my groups to open.
in that last 2 groups i shot with the brake,then without the brake.
group opened up without the brake.

[MustangMike]

i was making that in refernce to rsterne's comment about the brake causing the problem...

also i think maybe you need to figure out why ur breech is moving, unless on the previous page you explained that and i missed it. but my disco's breech does not move with out with our a scope...  i think youre problem might actually lay with the movent in the breech

[one_shot]

i was making that in refernce to rsterne's comment about the brake causing the problem...

also i think maybe you need to figure out why ur breech is moving, unless on the previous page you explained that and i missed it. but my disco's breech does not move with out with our a scope...  i think youre problem might actually lay with the movent in the breech

i agree....the breech moving needs to stop,ill tear into the gun tonight and investigate some.

[one_shot]

ok....i couldnt wait.

the screw beneeth the bolt was 1 full turn loose.
ive tightened the screw,reinstalled everything...including a slight stretch on the hammer spring while i was there.
i know its not a permanant solution to more fps....but it will give me a thirst for more power.
done it to my 2260,gained almost 100 fps.
unfortunatly my chronny is down,due to a stray shot from my npxl...ive shot the rear sensor...destroying the little concave lens that covers the sensor.making the chronny hard to use,sun has to be directly overhead,casting the shade of the difuser over the sensor.
maybe tomorrow ill fool with it.
i know before the mod i was in the 840 fps mark at 1800 psi.

anyway,the breech still moves alittle,but not like it was before.
ive tested with the scope,groups are all under a dime.next is to test with the open sights to see if this solved anything.
feels slightly more powerful,consumes alittle more air.

[MustangMike]

That breech screw might have a damaged thread or the hole it screws into might have a damaged thread in it or a peice of dirt is stuck to a thread.. it really shouldn't be moving at all

[one_shot]

ill pull the gun down further tonight,my groups got better.
lost about 5 shots per fill because of the hammer spring....but its worth a few extra fps.
i get less drop now.
from 2400 to 1500 is only a 1/4 inch drop in poi.

[MustangMike]

ill pull the gun down further tonight,my groups got better.
lost about 5 shots per fill because of the hammer spring....but its worth a few extra fps.
i get less drop now.
from 2400 to 1500 is only a 1/4 inch drop in poi.

it may only be a 1/4in drop in the poi but the further out you shoot its going to drop more

[one_shot]

its way better with open sights now...still needs work though.

i printed the new groups on a target i shot before the screw tightning incident,this way its eaisier to compare my findings.
the last 3 groups almost look my scoped groups!
im impressed to say the least.

[one_shot]

ill pull the gun down further tonight,my groups got better.
lost about 5 shots per fill because of the hammer spring....but its worth a few extra fps.
i get less drop now.
from 2400 to 1500 is only a 1/4 inch drop in poi.

it may only be a 1/4in drop in the poi but the further out you shoot its going to drop more

oh yeah....i understand that principle.
the 1/4 in was just reference at my 10 yard mark.
i guess i need to learn the range of this gun all over agan....or just mod this gun soon to hit high 9's-1000 fps then learn it over again.

what would be involved in getting this gun to hit the 1000 mark with 14.3 grains.
please fill me head up with known mods .
if i lose accuracy at 1000 fps,ill just stay where im at with the disco,buy a .22 mrod for the added power.

also will i lose accuracy when pushing the fps higher?

[MustangMike]

why stay at 14.3gr pellets when ur pushing 950 to 1000fps ? why get the speeds it has now but with 18.1gr jsb pellets and be getting right around 30ft lbs.

if you dont want to up the pellet weight then just leave it as is now... i have a heavier hammer spring but dont have it installed because im fine with the stock power of a disco.. but ya never know once my 15.1gr jsbs are all used up i have 18.1s left i might just swap the hammer spring out then..

[RatRacer]

Wsup Nick.

[one_shot]

ah steve....i was just reading some old threads,seen a few of your post...i was like i wonder what hes been uptoo...lol
i been ok i guess,work alot,bought some toys ect.

how are you?

[rsterne]

I wouldn't push 14.3 gr. pellets past about 900 fps.... After that, I'd start using heavier pellets.... A heavier hammer spring, combined with a 2400 psi fill will give you about 28-30 FPE (depending on pellet weight) and about 24 shots per fill, refilling at about 1300 psi....

Bob

[MustangMike]

I wouldn't push 14.3 gr. pellets past about 900 fps.... After that, I'd start using heavier pellets.... A heavier hammer spring, combined with a 2400 psi fill will give you about 28-30 FPE (depending on pellet weight) and about 24 shots per fill, refilling at about 1300 psi....

Bob

is that 24 shots in general or 24 good shots that are almost the same poi ?

[one_shot]

I wouldn't push 14.3 gr. pellets past about 900 fps.... After that, I'd start using heavier pellets.... A heavier hammer spring, combined with a 2400 psi fill will give you about 28-30 FPE (depending on pellet weight) and about 24 shots per fill, refilling at about 1300 psi....

Bob

is that 24 shots in general or 24 good shots that are almost the same poi ?

x2

[rsterne]

24 shots within about 5% velocity range, highest to lowest.... The exact count depends on pellet weight, fill and refill pressures.... You can easily get 30 shots if you're not as fussy.... or shooting at closer range....

Bob

[Ribbonstone]

C-clamp across the front of the breech...then snuggle the screw up tight (but not tight enough to strip that horrid little allen head).  Will get all the slack out of it you can that way (but be aware...you will need to c-clamp it again to get the screw OUT without stripping it).

IF the transfer port is a little long (or dosesn't fit the recess in the barrel well) will act as a "teeter-totter" point....just will never get the breech to snuggle down tight to the air tube.

One other idea...one that really worked for me, but is a lot more work: inletted barrel badn right ahead of the breech.  Its job is to make sure the breech end is stable (its how the PCP Challenger is set up...figured it was worth a try on the Disco...and its worked well for me).



The "trick"  if you want to use a standard band AND want to keep the rear sight base is to measure and cut the rear sight base.  The "nub" goes on between the band and the breech...then the band...then the front section of sight base.

[MustangMike]

C-clamp across the front of the breech...then snuggle the screw up tight (but not tight enough to strip that horrid little allen head).  Will get all the slack out of it you can that way (but be aware...you will need to c-clamp it again to get the screw OUT without stripping it).

IF the transfer port is a little long (or dosesn't fit the recess in the barrel well) will act as a "teeter-totter" point....just will never get the breech to snuggle down tight to the air tube.

One other idea...one that really worked for me, but is a lot more work: inletted barrel badn right ahead of the breech.  Its job is to make sure the breech end is stable (its how the PCP Challenger is set up...figured it was worth a try on the Disco...and its worked well for me).



The "trick"  if you want to use a standard band AND want to keep the rear sight base is to measure and cut the rear sight base.  The "nub" goes on between the band and the breech...then the band...then the front section of sight base.

that is brillant, dremel with a grinding stone shouldnt take to long.. or using a drill press and a good clamping set up you could drill it  out larger... also would need to put a groove in the stock to fit the barrel band..


wait if it comes on the challenger that then wouldnt a challenger barrel band already be big enough

[Ribbonstone]

Bit of a repost... but some of this might give you ideas:



BANDS:
After looking over a Challenger PCP, realized what that rear band (just ahead of the action) was doing. The rear band was making the rear end of the barrel  and breech more stable.  Its job seems to be to pull the action down tight to the air tube.

Tried it on both a Discovery and a QB, and point of impact stability greatly increased. Adding a set screw front band seems to have eliminated wandering zero.

Due to the Discovery's dimensions, decided to fit this one ahead of the gauge. With the QB, can butt the rear band right up to the breech. Discoveries have a sight base that is too large for a standard band. Unless you use open sights, can abandon the sight base completely.  The other trick is to cut the sight base and fit the band between the two halves. Has a nicer look this way; makes people wonder where you got a band that fits over the sight base.

[MustangMike]

man gotta add this one to the list of diy mods..

i just mounted a weaver rail to the under side of the fore stock and put a laser on it. it was intended for weaver mounted bipod but now im putting the 2nd rail from wally world on the side of the stock for the laser.. zero the scope for 35yrds and zero the laser for 15yards.. once the rail is mounted im pulling the barrel bands off and seeing how much of a chore its going to be to inlet the barrel hole