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Messages - xyon

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Members Reviews / Re: B30-1 .177 teardown
« on: March 08, 2019, 07:56:33 AM »
Maybe I got a Friday afternoon "special".  The breech lead in was not sufficient, so when you closed the compression tube up to the breech it was shaving a ring off the back of the pellet. I decided to fix that myself rather than return it. The power has not increased with that fix, so I'm suspecting the breech seal and/or the main spring.

Members Reviews / Re: B30-1 .177 teardown
« on: March 04, 2019, 07:04:42 PM »
Maybe the piston seal has too much friction? What about the breech seal, is that good?

I think the tight seal could sap a bit of power, but I'm not sure how much. Gamo's often have very tight seals and they don't loose too much power over it.
From what I have read on the internet, these B30's often seem to have a weak spring, People have seen quite a large increase in power from replacing the spring.

Members Reviews / Re: B30-1 .177 teardown
« on: March 04, 2019, 06:59:22 PM »
I left out the auto trigger safety part when I reassembled it for testing. But I would not remove the anti bear trap from one of these as the sliding compression cylinder is well capable of severing any digits  left in the breech.  :P

Members Reviews / Re: B30-1 .177 teardown
« on: March 03, 2019, 09:52:44 AM »
Before reassembling I checked the piston and breech seals were holding pressure, I did note the piston seal is quite a tight fit, but I though I would test it as-is first.

Now the bad news, First thing I did was chrony it. 676 fpe with 8.44gr JSB exacts :-)
That is disappointingly less than what I had hoped for. I tried a couple of H&N FTT, but they were slower.

Question now is, what is wrong???

Should I take it back to gun city, or try to fix it myself?

Members Reviews / Re: B30-1 .177 teardown
« on: March 03, 2019, 09:36:31 AM »
Done a bit more with this. Since the last pic was of the spring, I'll mention that first. You can see the spring is quite dirty, it looks like they didn't wash it after heat treatment or something like that, a bit poor.

The trigger is interesting (to me at least) as it is not a t05 or t06. I'd be interested to know where the design came from. It has 2 claws, one on each side, that hold the piston latch rod. It has 2 screws that can be adjusted to give a 2 stage pull, which I have done. When I got it, the first stage screw (hmm or was it the second) was wound all the way in meaning there was only 1 stage. I have disassembled the trigger an de-burred and polished the sears. From the few shots I have made the pull weight is not too bad, but it's no t06. It is unusual in that the pull weight decreases as you pull the first stage.

Sorry no pics of it disassembled, forgot to take any.
The other thing to note about the trigger design, is the auto safety engagement happens as soon as you lift the cocking arm. This means the rifle cannot be de-cocked as the Diana can. The trigger is blocked when the cocking arm is not in its home position.

Members Reviews / B30-1 .177 teardown
« on: February 27, 2019, 07:02:13 PM »
I  bought a B30-1 from guncity a couple of days ago after seeing that they have them for $199. I got the .177 as I have a Diana 52 in .22 which this gun is a copy of, mostly that is.

This is what it looks like straight out of the box.

I was going to shoot a group with the open sights, but after a couple of shots I saw the rear sight was wobbling from side to side. When I got back inside I noticed the screw holding the sight in place was loose, so nothing to drastic there.

The finish on the wood is reasonable with no major flaws,  I have the Diana stock next to it for comparison

B30-1 above, Diana 52 action below

Quite similar as you can see.

First surprise for me, the trigger is not a T05 or T06, also the lack of washer on the cocking arm pivot has caused the paint to wear off after just a few shots.

On a positive note, the rear of the piston has a plastic bearing. The other surprise is the piston diameter is 26mm where as the Diana 48/52 is 28mm

The spring ends were ground a bit, but not enough, to stop them gouging the washer a bit.

Next I will clean up the spring, trigger and seal and reassemble for some testing.

Modifications / Re: Gamo Hunter 440 Tune / Modification
« on: February 13, 2019, 11:30:53 AM »
Good to see you got it all back together.
You mentioned burrs on the crown, one thing I noticed was that if you go over it again with new paste and very light pressure when grinding, you should be able to remove the burr.
I just did this recently on a Gamo shadow that had a crown that a pellet would drop 10mm into the barrel, WTF, looks like it was made with a tapered reamer.

Another thing I just though of, which I haven't tried, would be to reverse the direction of the drill a few times during the process.

Cheers James, I spotted that one too!

General Airgun Discussion / Re: Dive Tanks. Failures
« on: January 23, 2019, 06:47:12 AM »
fridge compressor will do 150 to 400 psi

For Sale, Wanted, Spotted / .177 Zorak Ultra Chrony
« on: January 22, 2019, 07:51:37 PM »
Chrony test of a .177 Zoraki with an Ultra length Walther barrel.
Pellets H&N Econ 7.48gr (weighed at 7.2 gr)

Pumps   fps
1       384   3.7
2       536   1.7
3       637   2.0
4       691

as the subject says, anyone got one they want to sell. I would trade it for a custom made spring guide for your spring air rifle.

General Airgun Discussion / Re: Visual Ammo. D54 Bullpup
« on: January 16, 2019, 12:01:39 AM »
Hi and Welcome,
Got a link for the visual ammo? for those of us who are too lazy to look it up :-)

Members Reviews / Re: Gamo G Challenger
« on: January 15, 2019, 11:57:35 PM »

Members Reviews / Re: Gamo G Challenger
« on: January 11, 2019, 12:48:14 PM »
The planed two stage trigger is not going well. So far my drawings have not come up with the answer.
 Even a rough mock up doesn't work with the Gamo trigger levers.
Should have realised that in the beginning. That is why the Charlie da Tuna GRT trigger is single stage.

The Charlie da Tuna GRT trigger is a 2 stage trigger.

Modifications / Re: Gamo Hunter 440 Tune / Modification
« on: January 11, 2019, 10:10:19 AM »
Did you finish your Gamo 440 project? I remember you mentioned you had one on kiwi airgunners when I posted about restoring my one.

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