What is tuning?



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Offline UlteriorModem

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Re: What is tuning?
« Reply #20 on: November 09, 2018, 05:39:47 PM »
I was able to find a Crossman seal at Pyramid air. Other types have been suggested but I will see how it is when it arrives.

Quick question what size screw for recrowning a .22 cal? Or is it not all that critical?

Offline Roadworthy

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Re: What is tuning?
« Reply #21 on: November 09, 2018, 07:13:21 PM »
The critical part is getting a brass one with a ROUND head.  I think a number six or number eight should do nicely.  It simply needs to be large enough not to fit into the bore.   You want to polish the perimeter of the bore where the pellet exits, not the bore itself.
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Offline UlteriorModem

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Re: What is tuning?
« Reply #22 on: November 10, 2018, 04:32:28 PM »
Thanks for the input everyone. Still waiting on the tools and parts for the full tear down and 'tune'.

But I did the breech thing this morning. It was easy.

The results? At first I was cursing shooting about 2 dozen JSB's they were all over the place "Nothing has changed" I thought.

I switched to some H&N FTT's and things started to tighten up some. I dont know if it was the pellets or the fact that there had been a couple of dozen rounds down the pipe after the thorough cleaning I gave it after the crowning.

Lastly I switched to CPD's I was pleasently surprised to see things tighten up nicely. 3/4" group at 20 yards, and it was a little breezy. Still have a few flyers come out, way to many like 1 in 5 or 6 or so :P This gun sorta liked SPD's when I first got it before it went south. I am glad that it does once again. Hope to sort a tin tonight and try to weed out the potential flyers.

Anyhow I wish I had gotten better pictures, should have used my camera instead of my phone. Oh well the deed is done.

20181110_121639 by Tom Whit, on Flickr
Before, told you it was not a good picture. But there was no 'crown' per se. It was just flat off, but it was clean but what the heck I cant hurt anything right?

20181110_123751 by Tom Whit, on Flickr
After.

I wish I had a buffing pad but forgot to pick one up, I will do that later.

So thanks again and stay tuned :D


Offline Tucannon

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Re: What is tuning?
« Reply #23 on: November 10, 2018, 06:34:07 PM »
That should help, looks better, I would put 20 or 30 through it and see hoe it holds up.
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Offline Lone Star

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Re: What is tuning?
« Reply #24 on: November 10, 2018, 08:31:49 PM »
Been having similar problems with my Titan. Just checked the barrel and I have no noticeable side to side movement but I tried up and down, what a mess. Lockup not worthy, no wonder my shots were rising and falling so badly. Any advice would be greatly appreciated as I will be tearing it down shortly to address this and doing a full tinker, oops I mean tune.
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Offline UlteriorModem

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Re: What is tuning?
« Reply #25 on: November 10, 2018, 08:35:09 PM »
Been having similar problems with my Titan. Just checked the barrel and I have no noticeable side to side movement but I tried up and down, what a mess. Lockup not worthy, no wonder my shots were rising and falling so badly. Any advice would be greatly appreciated as I will be tearing it down shortly to address this and doing a full tinker, oops I mean tune.

Take the stock off and check the pivot pin / screw. Bet it is loose!

Online Bryan H.

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Re: What is tuning?
« Reply #26 on: November 10, 2018, 08:44:02 PM »
Been having similar problems with my Titan. Just checked the barrel and I have no noticeable side to side movement but I tried up and down, what a mess. Lockup not worthy, no wonder my shots were rising and falling so badly. Any advice would be greatly appreciated as I will be tearing it down shortly to address this and doing a full tinker, oops I mean tune.

Take the stock off and check the pivot pin / screw. Bet it is loose!

Bet it is
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Online bandg

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Re: What is tuning?
« Reply #27 on: November 10, 2018, 09:11:28 PM »
I had to work on a Hatsan 125 that had less than snug lockup-it also showed no lateral movement but a light tap on the bottom of the gun would cause a visible change at the point where the barrel block met the receiver i.e. barrel tilting down.  I removed the barrel and removed the lockup pin.  The hole was full of shavings/debris and the pin itself was rough.  Cleaned it all out, polished the surfaces of the pin, and shimmed the spring before reassembly (if you do this make sure that the pin will still compress fully into the hole).  Improved lockup on that rifle dramatically.
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Offline UlteriorModem

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Re: What is tuning?
« Reply #28 on: November 12, 2018, 06:56:47 PM »
Well after the Titan sat around a day or two I took it out this afternoon and was quite pleased at it's performance. Maybe it just needed a nap after all the putzing around with it :D

20181112_172901 by Tom Whit, on Flickr

From 25 yards with Crossman CPD's and H&N FTT's it was a little breezy and a few flyers Those are roughly 2" targets.

Online Bryan H.

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Re: What is tuning?
« Reply #29 on: November 12, 2018, 07:49:40 PM »
Well after the Titan sat around a day or two I took it out this afternoon and was quite pleased at it's performance. Maybe it just needed a nap after all the putzing around with it :D

20181112_172901 by Tom Whit, on Flickr

From 25 yards with Crossman CPD's and H&N FTT's it was a little breezy and a few flyers Those are roughly 2" targets.

Very respectable.  I'd take it for $100.
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Offline UlteriorModem

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Re: What is tuning?
« Reply #30 on: November 12, 2018, 09:58:28 PM »
Heh that image is on its side. But I got a kick out of the top middle in that orientation... I had it surrounded :D

Speaking of 100 bucks, that's about what I paid for it, a pyramid air one day sale with some bullseye bucks!

Offline anti-squirrel

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Re: What is tuning?
« Reply #31 on: November 13, 2018, 02:26:57 PM »
Tom, that's respectable shooting for a $100 gun with only a few different types of pellets.

I will randomly buy different tins of pellets since I always end up with surprises.  My CZ springers likes any RWS pellet.  It also likes Crosman domes, but it ain't so good with JSBs.  I tried 13 different pellets before I shot groups I like in this gun.  Of course I had to go through half my box of tins before I got to the RWS pellets, but then it was like, AHA!

My Hatsan 95QE gas-piston has a hankering for Polymags and AA/JSB domes in the 25-to26-grain range. I got lucky and these were only the 4th pellet I tried.  The Hatsan 19.91 domes in .25 were too light for my tastes, though reasonably accurate.  Still, MAJOR difference between those lighter pellets and the gob-smacking Polymags.

My first B-3 underlever was a horrid clunky twangy abortion of chinese pallet-lumber, poorly-stamped metal, and a retarded machining job for the receiver, yet after less than an hour of effort, it evolved to far away the most brutally accurate airgun considering the 10# trigger.  I passed it on without a true tune (I just degreased the spring and cleaned the leade and crown) and the current owner takes a few pests a week with that thing using simple .22 Crosman domes.  It impressed me so much I bought a second B-3 that was in every regard(except shooting) a much better example, and I ended up wrapping that piece of excrement around several trees. Sometimes, you just cannot win.  It gave me $40 worth of tree-wrapping excitement, at least.

I had a Crosman Optimus .22.  Twangy until degreased, and once recrowned, it stopped liking Crosman domes and developed a taste for JSB/AA domes.  Anything over 15 grains but under 19, really. Right now, it puts meat in the fridge during Winter squirrel season for the current owner.

My point is that you tweak the stuff you can, like the leade (where you load the pellet), the lock-up, the crown, and make sure the screws are tight, but in the end, you gotta play around with a lot of pellets to find the magic combination.  Some airguns, there's just no explaining why they prefer a certain pellet.  For example: My 392 pumper loves Gamo Redfire... I just roll with it.

So when you tune an airgun, be sure to do one thing at a time and then do some shooting with as many pellet types as you can, because sometimes you get surprised.


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> OHNOES I NEED ANOTHER <
and some slingshots for when the pellets get low

Offline UlteriorModem

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Re: What is tuning?
« Reply #32 on: November 13, 2018, 06:42:30 PM »
So the spring compressor showed up and a few small hitches with it but I managed to get the gas spring and piston out. The seal looks to be in pretty good shape.

Once I get the compression tube cleaned up and some sharp edges attended to it will be time to put it back together.

But I am a little confused as to which grease to apply to the actual piston.

I have some PTFE grease "Super Lube" will that be okay?

Offline Xptical

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Re: What is tuning?
« Reply #33 on: November 13, 2018, 08:29:24 PM »
I crowned my rifles (deep target crown) before I ran across this:

https://rifleshooter.com/2018/03/do-rifle-crowns-matter-does-a-crown-effect-accuracy/

Kinda makes me rethink some of the things I "know" about the universe.


Then again, it might just be one random crazy person with a very lucky series of shots.
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Offline UlteriorModem

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Re: What is tuning?
« Reply #34 on: November 14, 2018, 02:10:32 PM »
So last night I got the spring compressor and decided to tear down the Titan.

I have to admit I was not prepared for what I encountered. What a frustrating, time consuming, and mentally exhausting task it turned into. Mostly due to unfamiliarity with the mechanics, but a lot due to the spring compressor itself.

I wont go into fine details but suffice it to say it took me over 4 hours start to finish, several dropped tools, some crawling around on the hands and knees looking for C clips, stuff like that. I will probably do a separate review on the 'rail lock' spring compressor but in a nutshell, it works... sort of, and not all that well.

A couple of stumbles where I got it all put back together and it would not cock due to the trigger assembly not being installed correctly. It is frustraing to be 'all done' but not.

In the end I got it all back together and it works, however I think I may have the gas piston in backwards :P

I will look into that tonight and weather permitting (doubtfull) run a few rounds through the chrony and accuracy tests to see if all this was worth it.

Offline Xptical

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Re: What is tuning?
« Reply #35 on: November 14, 2018, 05:47:33 PM »
To me, the frustrating part was that mine didn't really need anything major inside.

Other than a light deburring, the main parts were pretty nice.

My trigger was where the tuning paid off.  Got my sears to a mirror finish and the trigger pull is so smooth now.


I'm glad to see you making progress.  I've ripped mine down 3 times now and can just about do it without any references.
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Offline Novagun

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Re: What is tuning?
« Reply #36 on: November 14, 2018, 09:22:35 PM »
The original question has not yet been answered.
Here is an attempt.

Tuning an air rifle is the improvement of air rifle performance by the repair of production defects, the repair or replacement of substandard or defective parts, the improvement of the function of parts to the satisfaction of the user.
« Last Edit: November 15, 2018, 01:09:19 AM by Novagun »
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