QB-57 Mods and Tune Completed---- New Pics

[Gene_SC]

Ok, I finished up the first stage of my mods on the QB-57 today. Custom made Delrin Spring Guide, Apex Seal with Custom Button Adaptor, along with deburing and polishing everything that moves.. Although the QB-57 is similar in mechanics, it seems to be a step up in quality.. Don't get me wrong on that.. The action was one tube and not a formed tube like the B-3.. The trigger has linkage and is quite different feeling than the B-3. There are some other similarities but just similar. I spent most of the afternoon working on the trigger and linkage. I ended up loosing a couple E-Clips and only had one spare.. Had to get more at hardware store. When the trigger was all done I did the CDT 5 Stage Lube Tune... I took my time and did everything according to that Fritz told me.. He steals CDT's secrets now and passes them off to me when I bring him $50.00 a bag, Fritz Gourmet Dinners.. Anyway everything went together well and not hang ups. I had pre lubed the trigger and slipped it in as I closed the end cap up.. So now all I had to do was hook up the linkage to the trigger blade.. Well I lost the spring.. Dang... so I remembered I had about a dozen old Gamo trigger blades and spring left over from all my GRT-III trigger jobs.. Quickly grabbed one and it fit perfect. It was the return trigger blade linkage spring not part of the actual bear trap and trigger assembly.

So not I looked everything over and it looked fine. So I cocked her and my hand slipped because I had some grease still on my left palm.. Down comes the lever on my middle knuckle full force. Yikes did that hurt like the dickins.. Learned new lesson.. Clean hands before cocking.. hehe.. I have a knot on my knuckle the size of a golf ball now and both sides of my hand hurt bad.. And after all the lecturing CDT gives me a bout safety, I screwed up and almost broke my hand..

So anyway, I cleaned up and proceeded to cock her again. Cocked fine and I placed a pellet in the port.. Put it up on the chrony and Wa La first shot was 743 fps with Gamo Round Heads.. I ended up after 11 shots at about an average of 736 fps with less than 7 deviation. At this stage I was happy but no surprised. The Apex seal fit great in the cylinder after I cross hatched it with a hone. Allot of attention went into the making of the new seal button, as far as overall height, thickness of button verses seal and of course the retaining screw had to be recessed a bit for clearance. I am happy with the results of the mods on the QB-57 and I owe a big thanks to CDT for being nice enough to guide me through many of these processes, many times.. He has the patients of a saint cause I am as hard headed as they come... Just ask Fritz.. hehe

I forgot to mention that the initial FPS of the QB-57 was in the heigh 500's when I first checked it on the chrony before I tore into it.. I think this mod made a great deal of difference in the power. I am happy with my results and will not attempt to boost the FPS up any further.. My next step is to re-finish the stock, muzzle brake, and scope. My final thread to this post will be how accurate it is at 10 meters and at 35 to 40 yards.. Below are pics of the parts, new and old.. for this mod.

Gene

[JMG]

Hmm secret spring..... hmmm apex seal.... Gene I see the similarities of the B3 my question is about the piston and compression chamber and spring. Is this the QF2 kit spring? The apex seal is it the small or large? Is it one of the Tesla's? hehe. Is it the same piston and compression chamber as the B3? I like the idea that the receiver is a solid tube and not tack welded formed sheet. I had an interestingdiscovery when dismantling my B3#1 a week or so ago for its cosmetic make over.I was pulling the piston out of the compression chamber and noticed something kind of weird that I didnt notice while I installed it a month ago or so. The piston/seal assy. slid out very easy up to where the slot is for the cocking lever shoe then it got to what I think is the right friction tightness it should be for the entire length of the chamber. I came to the conclusion that the compression chamber got overhoned by that guy thats always hangin around... you know that Itwasntme dude. SO now I am prolly gonna have to go with a large apex in order to tighten that gun back up. Hmmm questions questions questions.

John

[Gene_SC]

John, I did not have a B-3 appart to compare lengths and O/D of the QB-57 and that is why I mentioned "Similar"... The Apex Seal is a 1" seal. Standard replacement for Gamo air rifles. The spring is a Gamo spring.. Outside of the this I just made the spring guide to CDT's specs with reference to the overall fit. Believe it or not there is a technique to fitting a spring guide to a new spring which, if done properly will really improve how the action sounds and feels. Absolutly no twang. Allot of time was spent on deburing and polishing the right spots for smooth cocking and trigger pull. One thing you really have to be carefull with is honeing the cylinder. One thing I did not mention in the process was that the port hole in cylinder was rough. I cleaned it up with emery cloth till it shined.

Gene

[JMG]

Interesting points Gene. As I said this was B3 #1 that I prolly went overboard on the honing so the QF2 kit seal slides in pretty easy. The problem is that the entrance into the chamber is still snug.... not tight but snug so I cant get a real good measurement. But if my memory serves me corrctly I think I figured out that I could use a large apex seal after whittling it down some. There was something Bob had said in another thread that caught my eye I wanted to ask about, but I seem to have lost the thread lol. My question is....Bob said he would run a spring to almost coil bound to set the preload. I found this kind of interesting because there are no tune guides that say where the upper limits of your spring preload is. They give you dimensions for washers... like saying 3/8" for a B3 for example. But I never really figured out how they came up with this. What Bob had said made a little sense and I am sure he was saying it as more of a rule of thumb and not a written in stone process. So my question is this.... I just want to make sureI am understanding this correctly maybe even Bob can chime in. Here we go basically when tuning a gun, you want to preload the spring up to where it is almost coilbound.... and then use whatever spacers you are using... tophat washers yadda yadda yadda to get that preload or a little less for safety's sake. I know each gun is different but am I on the right track? I am still using the B3 as my education since it will apply to most other spring/piston guns. Oh and just for giggles and grins Gene measure the B3 stock spring ya replaced and see if that gamo spring is anything close lol.

John

[Gene_SC]

John, on the preloading of spring, Bob will have to take over.. I will have to find my old B-3 spring if it is not in the trash already:) On the QB-57, the Gamo spring worked because by measuring the wire thinkness and amount of coils calculated out to a safe tolerance. Now Bob did the calculations but I do understand the relativity of it. I know there was more preload or spring compression on the Gamo spring compared to the stock spring..

Gene

[shadow]

Well buddy, you've been busy since I've been gone. Very nice Gene. Ed

[Gene_SC]

John

I think your question about the preloading etc. might follow under certain aspects of tuning that are privy to Bob (his trade secrets) and I’m sure that he won’t divulge many of them. After all, that’s how he makes a living (if you want to call it that). He’s always working with a digital micrometer, a pencil and paper and a calculator figuring out whatever it is that he’s working on. It has taken him years to perfect his tunes and he doesn’t tune a gun like you and me.
There are a couple of people out there, especially one, that just sits back and reads every post he makes. Then they use that information to their advantage and taking away from his business to improve theirs. Then when the old fart retires it will then have an impact on me….he he
We all know that Bob shares a lot but he does have his limits. What I’m saying, is I don’t think you will see him sharing information as to how he calculates and makes determinations about different weights and measurements regarding springs, tophats and guides. He’s teaching me and I’m learning and I am also beginning to learn what the limits of divulging information are. And some informtion, not even Fritz is allowed to know... hehe
And I am sure you and the other guys can understand what I am saying..

Gene

[JMG]

I understand exactly what you are saying Gene. Its like this.... my mom makes the best fried chicken I have ever tasted. Now growing up I have watched her do it so many times I cant even begin to count. She doesnt measure anything she doesnt time anything she has been doing it for so long she just knows what to do. The only way I believe a person can get to a fairly competant state is by putting the time in the excersises and having failures and successes. Hehe and ya cant blame a guy for trying to eek out a few tips from a master right? I doubt I will ever be a master airgun tuner. But.... I wouldnt mind being somewhat compeant at it for my own personal peace of mind hehe. Hopefully I will be gettin a new job soon and the funds will be a little more flowing. Seems things just keep on hittin me though. But one of these days I am tellin ya one of my guns is goin to Bob to get a full tilt Boogie!!!

John

[Gene_SC]

Just about completed my mods on the QB-57.  Just waiting for the scope and will post some pics... I think Ric will like a certain mod and he will just have to come and see it.. Should have the scope by tomorrow and mount everything up and shoot some targets.. I have about 500 pellets through it now and the FTS has come up to an average of 750fps with RWS Superdomes and Tomahawks. It shoots straight and dang accurate at 10 meters..

Gene

[shadow]

I'm getting all tingly inside waiting for the pic's buddy. Ed

[Gene_SC]

Ok guys, I did my best to make the QB-57 a fun project and I did succeed.. I am happy with the outcome and all the little whistles and bells.. bling, bling, bling.. hehe... I got my Tasco Golden Antler Scope today along with my New Simmons Master Series Air Rifle Scope..
But back to the QB-57.. Here is what the final out come looks like. If you have been reading my progress there  is no need to go over it again..

Gene

[CharlieDaTuna]

Now dat looks like one of dem tings day use over dere in Irock    

[shadow]

VERY IMPRESSIVE BUDDY..WOW!. That looks tough and I can't get over how she look's. Great job buddy, ok i'm getting one for sure now . Back to the mod and tuning table for me hehe. Ed

[Big_Bill]

Great Job Gene,

Outstanding photographs, and beautiful job !

Did you get a new camera

[Gene_SC]

LOL Bill, I looked at the menue and changed a setting.. I hope that was the culpret.. I am taking some more pictures tomorrow of my new Simmons Master Series Scope and we will see.. Thanks for the compliment on the QB-57.. It was a fun project gun for me. And it shoots dang good too.. I am going out in the back yard tomorrow night and see what I can shoot... hehe  in the dark..

Gene