Discovery

[Pete]

Every time I load a pellet , it feels like it gets held up on something.  I have to give it a good push to get it in to the chamber.  Would this be a normal condition or is there something not right?    Thanks Pete

[Truman]

I get the same thing! I think it's where the pellet is pushed over the hole for the air! I'm sure some guys here have either polished the inlet where the pellet goes in or had the problem sorted with a MAC1 tune! See who else chimes in on this because I might have a go at this myself one day!

[Curioguy]

I would also like know why this happens.  The other day I actually mangled a pellet when it hung up in the chamber after trying (forcing) to close the bolt.  I know, this is not a good practice.

[5thumbs]

You may benefit from polishing the area where the pellet is fed.  It is a pain to get the barrel off and then it took me about 30-45 minutes with 400grit sandpaper (formed in the shape of a cone), to get it to a mirror like finish.  This helped in the "smoothness" when loading, and also accuracy.  I suspected that an imperfection in this area was causing the "held up" feel when loading.   I also ordered another Disco from Mac-1.  It came polished.  I could tell because the pellet load area is black, but after I polished it it was "mirror like".  

[5thumbs]

I got this information from Mike T. over at TKO brakes.  As mentioned above, I followed these instructions with very good results for both loading pellets and accuracy.  Wanted to provide the details that Mike provided and also indicate that I used 600grit, not 400grit.


RE: The barrel lead in.

The lead-in to the bore of the barrel contains a short taper, the port were  air enters the barrel and the beginning of the rifling. That area  should  be  smoothed out so there isn't any pellet deformation when loaded. The  bolt should slide in smoothly without any catching when the pellet  enters the bore and engages the rifling. The #1 detriment to  accuracy is if the  pellet  skirt is damaged on loading.     You would need a small lathe or drill press to do a quick, perfect  job,  but  you can roll up some 600 grit wet-dry sandpaper (used for automotive  finishing) and make a tight cone out of it and using a twisting  motion, polish the bore lead-in. You need to make a slow-tapered  cone so it will enter the breech end of the barrel about 1/2".     You would need to make 5-6 of the sandpaper cones and work at it for  30 minutes or so. That fine grit paper won't remove much metal, but  will  smooth  out the area and make loading smooth as glass.

[Pete]

Is it a real big pain to remove the barrel to do this touch up ? Is the breech thats needs the work or the barrel ?

[5thumbs]

It is the barrel.   If you take your time and work slowly, it  is kind of fun.   1st time you take it apart it is like a big puzzle (for me anyway),   2nd time is easy.

[Pete]

Is there any pics that would show how to do this fix ?
                                 Thanks Pete

[5thumbs]

I dont have pictures.  Get a hold of the Disco parts diagram.  I wrote this up awhile back

Barrell at Crosman is $15
Click on the Discovery page to get the schematic
Have fun with this puzzle. Not sure this is the most efficient way to take it apart. Dont be a dumb a$$ and over tighten like I did!

1.   Empty Air chamber (Optional but I highly recommend)
2.   Remove scope.
3.   Remove trigger safety (part 5) by moving spring (part 3).
4.   Remove stock (via screw 31)
5.   Remove Trigger (screws 26 and 22)
6.   Remove plug tube #17 and Breech plug #16 with screw #27
7.   Remove bolt handle (#15)
8.   Remove barrel band (part 21)
9.   Slide bold back (bolt #14), this gives you access to the infamous screw 29
10.   remove 29 and now the entire thing comes apart.
11.   Be very careful not to loose part #23 (it fell out on me and I put the entire thing back together). Part 23 mates the air chamber to the barrel. If not for this part you could just slide the barrel off.
12.   Loosen screw 28 and the screw under the rear site.
13. Barrell slides out.


TAKE YOUR TIME and have fun with it. I always rush the 1st time and the anxiety takes the fun out of it. Good luck.

[Pete]

Well I did the polishing job on the barrel. I put everything back together , the pellets load very smooth now. But I can not sight the rifle back in .  Poi is a foot to the left and its like everything I try I can not hit the paper.  I have no pieces left over any suggestion as to what might be going on ?    
               Thanks Pete

[5thumbs]

Pete,   I hope I did not send you off in the wrong direction.   The only thing I can think of is the obvious.   Either the barrel band or loosening/tightening the screws that hold the barrel in place.   Undoubtibly you have tried these things.    Is the POI consistant?

[Pete]

5 Thumbs
     Iam sure its something that I did. I tried the barrel band, but I did not think of the set screws that hold the barrel.  That will be my next move !   I sure hope that the scope didnt take a poop.
                                Thanks Pete       If ya think of any thing else   YELL

[Pete]

5 Thumbs
     I just took a good look  and the breech does not sit flush to the air tube, I can slide a piece of paper, from the front of breech  down to where the port from the air tube connects to the barre. Is this normal ? Pete

[5thumbs]

I see no gap, however I can slide a thin piece of paper (a reciept) in there.  However, it gets stuck on something and cannot get past to the pellet lead in.   Do you feel any puffs of air around the breech when you fire and has FPS dropped?   When I initially took the thing apart there was a little round connector between the air tube and breech.  Be careful to seat this back in correctly.

[Pete]

I put everything back together dont know what I did different , but its back to shooting where I look, even with the over 60 eyes.  All the work was worth it , the pellets load very smooth now, no ,more forceing  .
                                     Thanks for all the Info  
                                              Pete
   Ps   I still have the space beteween the air tube and the breech I guess this in normal.