Novice Tune-Up on a B3-1

[70GTvert]

Yup, right up there. Now look around and see how much it would cost to buy a new gun with those #'s advertised right from the start. Plus, odds are they would not do what was promised either. Now for the good news, That spring was far harder to put in then a replacement Gamo Big Cat spring. And the overall design is both cruder and more difficult to, so if you ever get a Cat, it will be a breeze. Same with many others to. The RS-2 has the need for an adapter for the spring compressor, but even it is basically the same.

[hyounker]

Dave,

I have not tried to space the spring yet.  It was a bear to get that thing in there, and my first attempt at a spring compressor is dying a slow death.  Don't want to risk to much pressure just yet.  I have some oak blocks in the works for my second attempt at a spring compressor.

Nonetheless, I walked around the backyard today and fired about 50 rounds at just about anything that has no worth!  Fun, but I was really just trying to shoot the rifle as much as possible.  I'll probably chrony some more rounds tomorrow after church.  

Thanks for all your help and input on this project!  I have a few scope mounts and a compact scope on the way and I can't wait to get this thing together with all the parts and see how she holds a group.

[hyounker]

John,

Amen!!  Not to mention the testosterone one generates disassembling and reassembling a gun!  Endless worth!

I have a Gamo 850 and that will be my next project.  And I am still looking hard at that RS2.  I fondled one at Wal-Mart the other day, and at that price, one will be part of my future!

New scope and mounts on the way!

[davee1]

Your Welcome...one thing that I forgot tomention was that after you get the QF2 spring in there and actually cock the B3, the spring takes a "set" and actually gets shorter than it was when it was new and unset. The forces that you felt when you installed the QF2 spring are quite powerful...and one can easily see why everyone warns of the risk of injury. The good news is that now that the spring has set, it will be a little easier to get out/in...but still dangerous. So I'm glad that you don't want to take any chances about your spring compressor breaking on you. I bought one of those cool B-Square compressors that used to be available a few years ago...its built like a tank...but it was expensive. At first I used a pipe clamp type spring compressor, but that didn't feel right to me, so I jumped for the B-square. Sounds like you have a good design for your compressor, because you have no injuries...now you just need to make it a little stronger. I'm going to take a picture of my B-Square to stimulate the creative juices...maybe you'll see something that you can incorporate into your own compressor. Look for that pic in a little while in this thread.

[davee1]

In all its splendor

[ronbeaux]

I'm glad I read through this post. I got my 97 taken down and waiting on lube to get here to put it back together. Looks like I'll be hunting me up some washers for the bearing and the spring ends. And soaking the leather seal.

[hyounker]

After installing the new qf2 spring, it didn't take long to realize that something was wrong inside the b3.  I tried to cock it after about 120 shots, and something was grinding.

I took it apart to find that the oilite bearing that I had placed over the rounded end of the original spring guide had broken into three pieces.  Probably not a surprise, as it was unsupported around its perimeter.  However, the oilite bearing in the pistion was in perfect condition with no wear at all.

So far, I would say that the oilite bearings will hold up fine, if they are laying flat and completed supported.  My guess is that if I had placed a couple stainless or carbon steel washers under the oilite bearing on the spring guide, it would have held up fine.

Nonetheless, my new spring guide will fix the problem of the round end on the original spring guide, so this will be a non-issue.  I'll continue check the oilite bearing in the piston for wear each time I disassemble the rifle (which is about 3-4 times a day!!!).

[davee1]

Yep, sounds like those bronzies need support. They are being subjected to incredible forces inside of there, and then the stronger QF2 spring did that one bronzie in. Hopefully they will hold up with more support. It will be interesting when you start with the spacing experiments to see if they still hold up. LOL we always end up at whats the worst that could happen?

[hyounker]

Thanks to a friend and Kev (mcmi), I was able to replace the factory spring guide with a new aluminum one that also incorporates the cover, eliminating that ugly plastic cap.

I also bought a clevis pin and was able to grind the head thin enough to use as the main spring pin.  There was excess room around the action, so I didn't have to break out the dremel for any stock work.

With the qf2 spring and the new spring guide, I am still averaging just under 700 fps.  I took all the sites off, so I can't see just how accurate it is yet.  I've got a Leapers compact scope and one piece offset mount here, just need to find some time!

Thanks again to mcmi and davee1 for the ideas to help me solve some of the problems with this old gun.

[shadow]

Looking good keep us updated, we all like to hear how the B's are doing. Ed

[mcmi]

This looks sweet. You did a nice job on the aluminum spring guide. It looks like a really nice fit. Keep us posted, brother.

[hyounker]

Has anyone punched any holes in the B3s for scope stops.  I thought about mounting the scope the way I want it, then using the mounts existing scope stop pins to mark where holes should be.

Any advise?  Should I drill all the way through, or how deep?

Thanks, as always!

[davee1]

That looks fantastic Henry!!!

About those scope stop holes...I've been pondering the very same thing. I think the most solid way is to drill and threada hole or holes all the way through into the spring guide. This would allow a metal piece of some kind to act as a scopestop. Of course this would all be behind the moving parts and spring of the B3. So you would have a metal piece with holes drilled in it, aligning with the holes going all the way into the spring guide, and then screws going thru the metal piece into the threaded holes. Thread the holes into the spring guide with 10-32 or so, something easy, readily available, and beefy enough to act as a scopestop. Thats the way I'm gonna do it when I get around to it...in the mean time I'm using the open sights.

[mcmi]

hyounker - 2/1/2009  2:39 PM

Has anyone punched any holes in the B3s for scope stops.  I thought about mounting the scope the way I want it, then using the mounts existing scope stop pins to mark where holes should be.

Any advise?  Should I drill all the way through, or how deep?

Thanks, as always!

Get the scope set up where you want it and use a transfer punch to locate the spot you want to drill. A transfer punch of the right size will fit perfectly into the hole provided for the set screw and allow you to perfectly transfer it's center location onto the rail.

I just drilled mine right through and cleaned the inside up with a file.