Springer mods question
Printed From: Kiwi Airgunners
Category: Technical
Forum Name: Pauly's Technical Area
Forum Description: Technical information, Modifications and DIY projects are all in here
URL: www.kiwiairgunners.co.nz/forum_posts.asp?TID=1139
Printed Date: 05 Dec 2024 at 8:49am
Software Version: Web Wiz Forums 10.14 - http://www.webwizforums.com
Topic: Springer mods question
Posted By: JasonEdward
Subject: Springer mods question
Date Posted: 01 Dec 2024 at 12:46pm
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You good bastards have me entering a new phase in shooting, basically wanting to improve my springer shooting. I guess there is nothing simple or YES/NO about these questions but they may be of interest to a few of us bunnies: 1. Is a tuning kit likely to SIGNIFICANTLY improve my springer shooting? If so which would you recommend for my HW80/Diana52? I'm capable and have tools to carefully fit a kit but no workshop to engineer serious mods apart from gentle smoothing of metal parts...and I'm familiar with and not at all disturbed by the sound and can feel no grating/cycling issues with my twangy springers. 2. I have both 177 and 22 barrels for the HW80 - again purely for accurate shooting would using the 22 barrel make sense for this reasonably high powered springer - i.e. to keep muzzle velocity down for pellet stability during travel? For this reason alone I'm kind of thinking of focusing on the Weirhauch rather than the 177 Diana. A few chrono results tell me the HW80 at .22 gives 730 ft per sec/17.4 ft/lbs, the D52 839 fps/16.7 ft/lbs. Chinese chrono with cardboard roof to shade sensors is very hit miss refusing to measure with no error msg at times and works reasonably reliably at other times. But in any case I'm not 100% confident in those measures and I'm considering an FX chrono for easy use attached to rifle and actually getting results every time I use it... These are quick bunny questions with likely many many varied and detailed answers possible -so don't shoot me down as a pesky pesty bunny unless you really need to please  but do tell me in no uncertain terms if my thinking or questions are stoopid. I'm here to leech off ... oops I mean learn from those who know from experience.
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Replies:
Posted By: kruzaroad
Date Posted: 01 Dec 2024 at 1:11pm
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What's the velocity of the 177 jw80? If it's under transonic then you'll only be dealing with windage. For accuracy a 177 is a much easier gun as the curve of pellet on flight is less. I'm personally in two minds about windage, I've found the ftt preform excellent in wind. I've shot some windy days. That's a low weight 22 pellet but short. The sig was sweet to fire in the wind too. It was 177 As for the Chrono graph great if your doing pellet testing, getting the power of your gun, nice to play with The reality for me is once you know all that and of your sticking to a couple of guns and ammo they really don't get used a lot. I've never replace mine after I killed it. Don't really have any use for it, possibly to check guns for air leaks. Wouldn' get anything that attaches to the rifle barrel. Wind meter might be more useful. It's also something tou can use in the field |
Posted By: RangerPete
Date Posted: 01 Dec 2024 at 7:18pm
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Hi Mark, As Kruza has asked, what velocity is your HW80 doing with the .177's Tuning kits for high powered springers usually reduce velocity a bit, and give a smoother, quieter shot cycle. I have never put a tuning kit in a springer my self, so i'm just speculating about their performance, but I believe they dont actually make a rifle "more accurate". They do make the rifle smoother and have less of a "violent" shot cycle, which in turn makes them "easier" to shoot and thus your accuracy should improve, if that makes sense? There are a few very good and widely respected tuning kits for the HW, and I'm sure there are for the D52 as well. As far as caliber selection goes for which rifle to tune, there is a general perception that .177 is more accurate than .22. I'm not sure I believe that my self though. I think as a shooter/rifle combination, most people will be able to "hit what they are aiming for" more often with a .177, because of its faster, flatter trajectory, giving the perception that a .177 is more accurate. However, I think if you separate the shooter element from the rifle, put a .177 and a .22 each into a shooting machine and do a 5 shot group with each... with all else equal, there is no reason why they should not each give as tight a group as the other. So if you are wondering which rifle to get a tuning kit for, I'd say dont worry about caliber, rather ask your self which rifle will you shoot more? which is lighter, fits you better, gives you more shooting pleasure, which do you use more often...? Thats the one you should start spending money on first. ------------- Walk quietly, but carry a big stick. |
Posted By: nunga
Date Posted: 01 Dec 2024 at 7:56pm
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Well tune kits are mainly to reduce the "twang" from the spring. They normally consist of a sleeve that goes inside the spring to reduce the vibrations when it is firing. This reduces the vibrations going into the barrel which improves accuracy. You can do a poor mans tune kit to see how that works. The poor mans tune kit consists of a plastic bottle and a oring. You cut the bottle top and bottom off then cut it from top to bottom. then you can put that inside your spring, just make sure you cut it to the right height to match your stroke of the gun which is around 120mm from memory. then you get the oring and put it inside the piston between the top hat and piston and you are good to go! ------------- 2nd place HP springer - WFTF World Championships 2014 |
Posted By: kruzaroad
Date Posted: 01 Dec 2024 at 10:12pm
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Probly true Pete. But shooter is part of the equation and with springers it's the drop that gets ppl. I prefure it myself as I can segment the distance better through the scope. As an example I can judge the distance at 67m better because the drop between 65m and 70m is steeper than a 177 of equivalent of power. Having said that, I imagine a pcp can be adjusted to negate that drop. I personally don't like a long slow arc in an air rifle as it takes very little to miss a vital and the impact shock isn't there. Having said that longest kill was with 177. Sig asp20. Exceptional break barrel rifle, just don't like 177, so I gave it away to someone who will appreciate it more went back to 22. |
Posted By: jwabfrog
Date Posted: 02 Dec 2024 at 9:10am
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I fitted Tinbum kits to numerous HW's, whilst they eliminate spring twang they didn't change accuracy like night and day. Other kit makers like Vortek have a solid reputation but are much pricier (more than I was willing to spend). Most of the off the shelf kits (Tinbum, Vortek, Maccari) aim to control the spring movement. Taking the concept even further, you can also guide the piston itself (like Air Arms do from factory) so that it doesn't slap around inside the compression tube - this can be done by cutting slots into the piston and fitting a seal. Have a look on Facebook: lots of British tuners producing extreme air rifle mod porn e.g. "glided pistons".
My understanding of tuning is achieving the ideal compression of air and release into the barrel. To change the compression behaviour you can also play with: - transfer port size (not something I've ever done as you can easily balls up a gun and a few 10ths of a mm can make a big difference. - piston weight (lighter piston will accelerate faster but carries less momentum so can bounce if too light) - seal size (I put an Australian Custom Air seals piston seal in a HW80 that was way too tight and caused a big drop in power) - honing (compression tubes aren't made perfectly round internally) There is definitely a sweet spot that changes with guns and calibre (i.e. if you tune your HW80 for 177, the same tune may not work with the 22 barrel installed). There is a famous tuning book "The air gun, from trigger to target" by Cardrew that deals with the science of tuning. I've got a PDF copy if you're interested. |
Posted By: RangerPete
Date Posted: 02 Dec 2024 at 11:56am
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Hi Jawbfrog, I'd definatly be interested in that ebook! ------------- Walk quietly, but carry a big stick. |
Posted By: Pauly5
Date Posted: 02 Dec 2024 at 3:48pm
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Can't add more than what has already been said. But another thing that can be added is a piston extension that "short strokes" the firing cycle. This will make your shot cycle snappier and reduce power a touch due to less air volume being pushed. I quite liked the feel, and reduced recoil. thay are approx 10 mm. But consult someone like Nick at Tinbum tuning, as he will know what you need to get the result you're after.
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