Barrel Movement Solution...???

[Trajan003]

Hey guys,  I have a gamo whisper and I am experiencing  A LOT of barrel movement and wanted to try and tighten the screws.  However, I lost the tool I need.  What is that kind of tool called and what size is it?  I gotta try and fix the barrel movement as my gun is shooting all over the place!  Frustrating since I bought the gun less than a year ago....   Thanks for the help!!!

Dennis

NEVER MIND!  FOUND IT.  :-)

[gamo2hammerli]

Since you posted.....   It's the Torx screwdrivers you'll need for the Gamos.  Don't know what size though for that barrel pivot screw.  Let us know how it goes.....since I've read that that screw/bolt is really tight....maybe even epoxied on.

[Trajan003]

I ordered a pack of shims from mcmaster.com and as soon as I get them I am going to try put them  one each side of the barrel pivot screw.  We will see if it works.  I know it didn't for some but my barrel sway is getting so bad I have to give it a try.  I attached my original post so anyone can look back at the history behind this post and check out the description of the shims I ordered.  If it goes well and anyone is interested in trying it out just let me know.  I had to order 25 shims and don't have any other use for them so I would be willing to send a pair out to anyone interested.

Dennis

THE OLD POST...

  http://www.gatewaytoairguns.com/airguns/forums/thread-view.asp?tid=22557&mid=179340#M179340

THE SHIMS FORM MCMASTER.COM

1    1 Pack    99040A505    
18-8 SS Precision Shaft Spacing Shim .005" Thick, .250" ID, .375" OD, Packs of 25 (Same as 99040A500)

[Trajan003]

Didn't work, gonna try a different size.  I think .005 Thick - .25 Inside Diameter - and 7/8 Outside Diameter is exactly what I need but I can't find it anywhere...

[Trajan003]

I ended up with a round shim with an inside diameter of .35 (glad I had the extra room to work with), I went way up to a .01 thickness, and about a .81 outside diameter.  It took a little work but i managed to get a shim on each side of the pivot screw which made for a total of .02 thickness added.  I love the results so far.  The movement feels like it is all gone and very snug.  We'll see how she shoots next time I am at the in-laws.  I am happy with the results so far.

[Bogey]

Dennis,  did you have to remove the barrel?  Or did you just work the shims into place from the side of the barrel hinge?

I just worked on a Crosman Quest type that had a canted situation.  The plastic washers that come with the Ag are marginal at best.   Made new washers from brass washers that I turned down to fit.    Luckily it worked out great with the barrel centered in what I call the forks and not  leaning  towards  the right.

Congrats on your ingenuity.  Hope it stays fixed for you.

[gamo2hammerli]

Dennis, as Bogey asked....did you need to remove the barrel or just slip the shims down onto the pivot bolt/screw?  Read that the Torx head is pretty easy to strip....and Gamo really screwed it in tight....maybe even epoxied it.  Had no problems with the Crosmans' though....they use a flat-head screw head.

[Trajan003]

Yeah, I had to remove the barrel and I put a shim on each side of the barrel before putting the pivot screw back in.  Getting the shims to stay in the right place as I but the barrel back on was the hard part but it worked.

[Trajan003]

The screw was very tight but I used pliers to get a good grip on the screw driver I used to unscrew the pivot screw.  Then when I screwed it back in I used just a little Blue Loctite on the screw.  I made it really tight and didn't have any issues.  Like I said before, the hardest part was getting the barrel back on with the shims as it added a total of .02 thickness at the pivot area.  I used a lubricant to help put the barrel back in place and it should also help when breaking the barrel.

[gamo2hammerli]

Thanks Dennis. Let us know how the BC shoots now. My BC have a very slight barrel movement also....I think that`s what making my longer shots` groups open up. Or the piston seal is starting or have worn out....have almost 8000 shots through her already!!!!!

[Trajan003]

I am pretty happy with the results...the barrel movement is gone all together and I am getting the groups I used too.  Now I just need to improve my shooting...  :-)

[LongIslandArcher]

Go to Lowe's, go to the fasteners aisle and in one of the drawers where the brass washers are, pick out a pack of 5/16" brass washers.  The outside and inside diameters are perfect for the recess in the breech block.  You might have to press them in with a C-clamp though, but once they're in, they won't come loose.  The fit to the forks should be just right without any free play.  Just make sure you moly lube them before you reinstall the barrel.  If they are too tight in the fork, take a flat file and file down the brass ever so much until they fit perfect.  I lucked out with my Crosman NPSS that came from the factory without ANY spacers.  A gunsmith at Gander Mountain told me to go to Lowe's to get these washers. The fit perfectly without any modifications and I'm shooting 1-1/2" groups at 65 yards with the gun.