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dummyracer36 · Senior Member

hi all, i tried searching for these answers and got a few answered, but i still have a few that remain. for instance have any of the mods been quantified at all? aside from aesthetics and stabilizing the barrel, are there any pre-made "hop-up" parts currently being made? or are there better parts from another make/model that can be easily made to fit? most of my experience is with magnum spring piston rifles, and this is my first Co2.

many thanks...

Dummy

AirGunEric · Site Admin

No existing 'hop up' parts that I am aware of are out there. You can get some more power by tightening up the hammer spring or adding weight to it and doing some valve modifications- ie. expanding the ports in the valve head. If you have one of the 'detuned' guns- i.e. those sold in Canada there are also modifications to be done that would bring the gun up to, and beyond U.S. factory specs.

The most you can expect out of a 1077 is around 750fps using a 7.9gr pellet- at that point you are shooting liquid/misting Co2 out the end of the barrel because it is too short to allow the Co2 to expand fully before coming out the muzzle. If expending a ton of Co2 is not an issue, there were at least two guys who had managed to get 1077s to around 900fps- with custom-made valves that had to be fit by cutting away the receiver to hold them, and they wasted a crapload of Co2 because of the barrel length.

If someone were to make a longer barrel tube and barrel shroud- then things might get more interesting...

dummyracer36 · Senior Member

thanks alot..... hadnt thought about a different barrel... hmmmmm maybe a .177 Benji Disco barrel..... the 1077 barrel is 20.38" while the Disco barrel is 24.25"

broommaster2000 · Moderator

That's a really thin barrel to begin with.

dummyracer36 · Senior Member

i'm thinkin a call to crosman is in order....... "reaching for credit card*.....
while i'm in there... gotta take a look at the Co2 fitting... i want to convert it to use the Avanti 2.5 oz refillable cylinder. it has a slightly smaller dia. than the crosman airsource.... which i think i can conceal easier in the new beech forestock i'm making. i want more capacity but dont like the looks of the airsource or any of the bulk fill conversions i've seen so far.

Slavia · Moderator

Do you have pictures?

dummyracer36 · Senior Member

not yet, i'll bring a camera to work with me sometime this week. not much to look at, other than a big block of wood with a bunch of pencil marks on it so far, dont want to start cutting until i decide on what Co2 source i'm going to use.

dummyracer36 · Senior Member

ok, design for the stock was finalized last night, and layout done this morning, made the first cut about 20 minutes ago, have taken lots of pics, but no clue how to post them on here?
any help?

Dummy

AirGunEric · Site Admin

You 'upload' them when you are typing your post. Look below the text box you are typing within and there is an "Add image to post" button. It takes you to a website where you upload the picture and then it inserts the proper information here. Click "Add image" again and put another picture up...

dummyracer36 · Senior Member

thanks alot!!! now to find the cord for the camera............

Jaxom · Senior Member

Keep us posting! I've got a 1077 also. Haven't done any mods yet, because this is my only survival rifle for putting food on the table. Don't wanna muck with it unless I have a back-up.