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All Springer/NP/PCP Air Gun Discussion General => Machine Shop Talk & AG Parts Machining => Show Off Your Air Guns With Mods (SHOW and TELL) => Topic started by: txrascal on July 27, 2012, 09:32:50 PM

Title: B3 alterations
Post by: txrascal on July 27, 2012, 09:32:50 PM
I joined this group a few days ago and thought I would post some pictures of my old Chinese air rifle.  I purchased it at a tool sale 15-20 years for I think $19.00.  You get what you pay for sometimes. It was not very accurate, anemic,  smoked badly and was heavy and ugly.  About a year ago I came across this some information on tuning this model and thought I would try it out.  The day the parts came in I was going to take some velocity measurements.  Cocked the rifle and something went snap.  I took it apart and found that the piston had broken.  I was able to weld it back together and it has stayed together to my amazement.

I also decided to see if I could make it look like something other than a club with a tube stuck to it.  Removed the paint with the help of a heat gun and shaped the stock to something that looks a little more like a rifle stock.  The wood has a lot of filler in it but with some stain and a Tru-Oil finish looks better that it did.  The rifle shoots at an average of 560 fps with most pellets. It is a lot lighter, points easier and fits my hand much better. It does not smoke and is fairly accurate although if you want to light matches with it you better have a lot of pellets.
 
Title: Re: B3 alterations
Post by: Fwawa20 on July 27, 2012, 10:01:37 PM
Yea I bought one of these about 10-12 years ago for $20 bucks myself. It shoots pretty good actually but lacks power. I Downloaded a PDF of the net to try and fix her up into a nice looking short range hunter but haven't got around to it. This would be my first tune and I know it's a cheap rifle but I'm still hesitant. I really like the suppressors ppl were making for them on this forum a whole back when there was a craze to tune them on here. I bought the things to make one myself but am unsure how to really make it even after reading the tuning guide. U might want to check it out
Here's the link I found:
http://www.kermitairgunclub.com/projects/b3guide/B-3%20guide.html#Making_a_muzzle_brake_for_the_B3 (http://www.kermitairgunclub.com/projects/b3guide/B-3%20guide.html#Making_a_muzzle_brake_for_the_B3)
Title: Re: B3 alterations
Post by: txrascal on July 27, 2012, 10:50:33 PM
That is the link I used and I tried to post it but couldn't get it to go through.  This the first time I've posted any thing so I probably just don't know how.  It really wasn't that difficult to tune and it certainly made a difference in the rifle.
Title: Re: B3 alterations
Post by: Fwawa20 on July 28, 2012, 10:48:27 AM
Yea how much more for did you get out of the gun? Did you chrony before and after?
Title: Re: B3 alterations
Post by: txrascal on July 28, 2012, 01:05:54 PM
I was going to crony before I started the rebuild and that is when the piston broke.  Some older tests had it shooting at around 490 fps but I don't think it was shooting that fast when I started the rebuild.  I get an average of 564 fps now.
Title: Re: B3 alterations
Post by: Fwawa20 on July 28, 2012, 06:15:21 PM
Nice good increase in velocity. Some members here have gotten 700fps out of some. I'm guessing those were .177's. Which caliber do you have?
Title: Re: B3 alterations
Post by: txrascal on July 29, 2012, 01:57:57 AM
It is a .177.  It will get over 700 with lead free light pellets but I don't like using them.  This rifle does best with Crossman Destroyer EX pellets.
Title: Re: B3 alterations
Post by: 4932msmith on July 30, 2012, 03:19:46 AM
txrascal, Gun looks great. I have two of these and of all the guns I own they are my favorite to shoot(now).   I don't have a chrony to test but I can tell you that replacing the spring with the QF2 parts kit will make a pretty obvious increase in power, but the most improvement can be made to the trigger, shot cycle, and crown. Mine will cut(have not lit one yet) matches at 10 yards 6/10 shots. Also since the QF2 kits are sometimes difficult to get, I have read in the archive section of this site about  using a crosman quest spring with excellent results. They are a lot of fun to tinker with, good luck with yours.
Title: Re: B3 alterations
Post by: stilkikin on August 29, 2012, 12:50:05 PM
You could always put a gas ram from a Titan in it.
Title: Re: B3 alterations
Post by: renowntwo on September 01, 2012, 07:24:40 PM
Very nice. Great job on the tune