GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: Whatsquirrel on September 04, 2015, 12:30:49 AM
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Just wondering how big of a difference an air stripper makes?
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Just wondering how big of a difference an air stripper makes?
It all depends on the gun it is used on.
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It all depends on the gun it is used on.
Wow! I'd have expected a bit better response myself seeing as I've researched this issue as of late.
:o
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x2...
Test setup.
(http://i245.photobucket.com/albums/gg76/gippeto_album/IMG_2459.jpg) (http://s245.photobucket.com/user/gippeto_album/media/IMG_2459.jpg.html)
Baseline;
(http://i245.photobucket.com/albums/gg76/gippeto_album/IMG_2457.jpg) (http://s245.photobucket.com/user/gippeto_album/media/IMG_2457.jpg.html)
Add the stripper..stripper/compensator in this case;
(http://i245.photobucket.com/albums/gg76/gippeto_album/IMG_2441.jpg) (http://s245.photobucket.com/user/gippeto_album/media/IMG_2441.jpg.html)
Initial set point of stripper;
(http://i245.photobucket.com/albums/gg76/gippeto_album/IMG_2458.jpg) (http://s245.photobucket.com/user/gippeto_album/media/IMG_2458.jpg.html)
After a little tuning;
(http://i245.photobucket.com/albums/gg76/gippeto_album/IMG_2461.jpg) (http://s245.photobucket.com/user/gippeto_album/media/IMG_2461.jpg.html)
Al
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It all depends on the gun it is used on.
Wow! I'd have expected a bit better response myself seeing as I've researched this issue as of late.
:o
How is this a bad response ?
Do you find it not true with your research ? if so, then please share your findings.
I still hold to my opinion. It depends on what gun it is used on, but to expand on it a bit I'll offer this up as a consideration.
Does your research include using a stripper on guns with already shrouded/baffled barrels ?
Does it take into consideration the weight of the pellets being shot and the velocities they are traveling at ?
Sure, Tim won extreme bench rest using one on his custom FT gun,...
but that does not mean they will provide the same level benefits on a Mrod, or a Gamo springer.
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Strippers can work, if they are concentric with the bore, and adjusted to the optimum gap for the pellet and velocity.... If any of those factors is wrong, they can be worse....
Bob
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Hang with some serious Bench Rest shooters .. or Field target either and :o
You likely won't see many.
YES they can work finding seconds of angle improvement when adjusted right.
Set up wrong or just there weight changing barrel harmonics with the unknown "is it right" will have most not screwing around with them at all.
POWDER BURNING applications are a whole different story ;)
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Just wondering how big of a difference an air stripper makes?
It all depends on the gun it is used on.
Air Force Condor.
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High speed ballistic photo
http://www.kuulapaa.com/home/highspeed.html (http://www.kuulapaa.com/home/highspeed.html)
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I have to side with Scott on this one.
I've played around with about every iteration of stripper available.....and made lots and lots of my own. I have never found a stripper to enhance accuracy. If everything is right.....you can have one that doesn't detract from accuracy, but that is as close to improvement as I have gotten.
First, it's important to understand that there is no such thing as a barrel that has a bore that is concentric and parallel to the outside of the barrel. This is easily verified with a good fitting gage pin, a test indicator, and a pile of barrels. You will need gage pins that, at the minimum, are in +/- .0005 ( .1755+, .1755-, etc) increments to find a decent fit. Put the pin in the end of the barrel and leave 2/3 sticking out. Dial on the pin closest to the muzzle, then as far from the muzzle as you can. If you have the barrel in a chuck or 5c, you will immediately notice that no matter how great your machine, or it's workholding fixtures......the pin won't dial true, and probably not even close. You will have to have independently adjustable spiders to get it right.....and it will take a long time to even get to .0005". Mine fits into the hydraulic chuck of my lathe.
OK....so now that we know there is no barrel that has an OD that is in line with the bore, it should not be difficult to understand why a stripper, LDC, or brake that mounts to the OD of the barrel will most likely never be truly aligned with the bore. Most accessories like this slip over the end, and use set screws to snug them down. Some are fastened via threads.....but if the threads were cut on the barrel while it was held in something other than a double spider and perfectly dialed.....they won't be true to the bore, either. This same logic applies to cutting precision crowns and leades.
If you are trying to wring out the last little bit of precision that your equipment has for competition.....this matters.
If any improvement has come from adding a stripper to the muzzle, it can likely be duplicated with a sliding weight......as the improvement is probably a harmonic thing and completely unrelated to the stripping effect.
I have heard really picky position shooters extolling the virtues of muzzle brakes on air rifles because they can reduce any felt recoil. If you understand that a muzzle brake can do nothing until the air that leaves the barrel acts upon them.....it's easy to see that the pellet is long gone before they do any damping.
I believe strippers and brakes are to airguns..... what watches, chains, and rings are to people. Accessories to make them look better. You can find good shooters that use them....but they typically won't tell you they shoot just as well without them.
I like the look of them , myself......but since I clean every 25-35 shots, I have found even nice looking strippers that don't harm performance to be a pain in the neck.
Mike
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The best method I have found for centering an Air Stripper is one I didn't invent.... I borrowed it from Tim @ Mac1.... You don't worry about the outside of the stripper being concentric, you have the hole in the stripper body oversize and use six set-screws, in two rows of three, at 120* spacing, to hold the stripper cone.... Tim uses a wood plug, turned to fit the bore and the ID of the stripper to hold the cone lined up with the bore, and then progressively tightens the setscrews to hold the cone there.... It doesn't matter if the outside of the barrel is concentric with the bore, or aligned axially, or if the threads or setscrews holding the body in place hold it straight or not.... You are aligning the cone with the bore.... I have modified one of my Hatsan strippers in this way, and I really like it, with one exception.... It is very difficult to slide the cone back and forth in small increments, and every time you do, you have to recenter it.... I need to do more testing, but so far I like what I see.... It may well be that once the cone is aligned perfectly with the bore, the spacing is much less critical....
Bob
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Good point it reference to the bore vs the od of the barrel not ture center.
As in crowns. Many chop the barrel and face the barrel work the od of the barrel then crown. You can get away with this but that is the reason the face and crowning tools cost what they do. A true face of the bore center and the crown down the same way is the best.
The borrowing of Tim is a good method to align the stripper and or brake. As important as the ldc alignmemt. This is one of the reasons for clipping of the baffles. Another in clipping is incorrect alignment of baffles and or off center holes.
Same on the stripper. Being off can case an I'll turbulence of air as the pellets exits the barrel.
I use a simular method as Tim for a slip on brake or ldc and so far I have had good results as far as alignment.Jmo
FANG
JUNKYARD AIRGUN'S
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Is really need Air Stipper ::)
http://imagizer.imageshack.us/v2/800x600q90/69/82si.jpg (http://imagizer.imageshack.us/v2/800x600q90/69/82si.jpg)
http://imagizer.imageshack.us/v2/800x600q90/812/nfah.jpg (http://imagizer.imageshack.us/v2/800x600q90/812/nfah.jpg)
http://imagizer.imageshack.us/v2/800x600q90/692/pdx4.jpg (http://imagizer.imageshack.us/v2/800x600q90/692/pdx4.jpg)
http://imagizer.imageshack.us/v2/800x600q90/801/q6co.jpg (http://imagizer.imageshack.us/v2/800x600q90/801/q6co.jpg)
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Love those photos.... but would love to see a comparison with a stripper in place, too....
Bob
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That third photo clearly could use one. Gas is clearly passing the projectile in flight
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michaelthomas; if you're having to clean every 25 to 35 shots it seems likely your pellets are very badly contaminated with something. Perhaps a wax or oil treatment messing up the barrel? Clean pellets fired out of an airgun at anything less than about 950fps should leave the bore very clean even after many thousands of shots, no cleaning necessary. My Pardini K12 holds perfect vise-tested groups after more than 50,000 shots with no cleaning and the bore looks perfect in strong light. Of course if you're shooting near or even above the speed of sound you'll probably get leading and need to clean... but why would you, as such high velocities tend to make pellets unstable.
As for a stripper being irrelevant due to the pellet being long gone before the air... um, no. Air is moving ahead of the pellet at the speed of the pellet. That air being rather disorderly it tends to influence the stability of the pellet unless a well fitted and properly tuned stripper is in use. That's a big part of why my Pardini is much more precise than my other airguns which lack stripper. The LW barrel on my Brocock Atomic for instance is perfectly crowned, very accurate, but still my 10 metre groups rested are at least 50% centre to centre larger than those from the Pardini. The Atomic lacks a stripper.
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Love those photos.... but would love to see a comparison with a stripper in place, too....
Bob
We will gather money, and record all interesting for us ;D
http://www.ebay.com/itm/WEEKLY-RATE-High-Speed-HD-Phantom-Camera-On-Site-Service-Slow-Motion-Rent-Rental-/252070265251 (http://www.ebay.com/itm/WEEKLY-RATE-High-Speed-HD-Phantom-Camera-On-Site-Service-Slow-Motion-Rent-Rental-/252070265251)
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Good idea for exact air stripper, machining barrel like this http://www.bellmtcs.com/store/index.php?cid=151 (http://www.bellmtcs.com/store/index.php?cid=151) and add this part http://www.blingairthing.com/droot/resource/images/shop/AAM0001-2_SML.jpg (http://www.blingairthing.com/droot/resource/images/shop/AAM0001-2_SML.jpg) (right part )
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Strippers can work, if they are concentric with the bore, and adjusted to the optimum gap for the pellet and velocity.... If any of those factors is wrong, they can be worse....
Bob
I think they can help when the barrel is a little too short for the power you're making and the pellet is getting moved around by the air following it. As soon as the pellet is flying the air pushing has to get out from behind it. I think the shape of the projectal lends itself to getting blown around if the air volume isn't just perfect. For sure the thing has to align with the bore or it will make things worse. The Stripper I make has the cone fixed by six screws (two rows of 3) so the mounting to the OD of the barrel does decide the direction it points but it can be adjusted from there by aligning with a pin in the bore to the center of the adjustable cone.
TimmyMac1
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Gerard,
You are not going to do well at a benchrest match without cleaning nearly every card. You can come up with any theory you would like to about that, but I have the empirical evidence on my side. Most of the people that own my rifles have tried to get away with a less frequent and less intensive cleaning process than I recommend....only to find their scores drastically declining. The only thing that restores the accuracy is a really thorough cleaning with some aggressive stuff, and cleaning every card thereafter. It has nothing to do with the pellets or bore being contaminated. It has to do with the fact that there is rifling inside a barrel, and we shoot lead pellets through them. Some pellet and barrel combinations like a sparkling barrel every card, while some can go a few cards in a moderately dirty state without throwing a flier.
I said muzzle brakes meant to reduce felt recoil are useless because the pellet is gone before they do anything.....so any "less" recoil you feel is not going to have any bearing on accuracy. Reducing the things that happen before the pellet leaves the barrel is a different matter.
Perhaps I don't get any better accuracy from a stripper because I tune my rifles to use the bare minimum amount of air to get the job done.
As Tim mentioned....if you are using a short barrel and have to really step on the valve to get the velocity you want.....maybe a stripper will be helpful.
Mike
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Really see no difference with my 2240, about teh same size group with or without.
On the discovery it throws the pellets right into the dirt, removed it instantly as the gun around shoots great at my hunting ranges
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Okay, so perhaps a bit of an apples and oranges thing going on, depending on the intended use. Still, my K12 has rifling same as any other good barrel. It's a hammer forged Pardini barrel making it one of the most precisely made, as the company has a stellar reputation for barrels among Olympic level shooters. Recoil isn't an issue because the tungsten cylinder being blown backwards from the breech as the moment the pellet is being blown forward cancels all recoil when correctly adjusted to a given velocity and pellet type. The air stripper has nothing to do with recoil, everything to do with managing air flow before, during, and just after pellet transition. It's adjustable, and I've played with it a fair bit, settling on the spacing which gives me the smallest groups. I've seen those groups open up considerably, as much as 20%, when the cone is in the wrong place. But groups actually open up even more than that if I clean my barrel, something I did at about 2,000 shots when I first owned the pistol. It took almost 100 shots for group size to close up again. Leading in for consistent lubrication seems to have been important in this case.
Many tests have demonstrated that the finest air pistols and air rifles from the same companies (Steyr, Pardini, Feinwerkbau, etc.) show either no difference in group sizes at 10 metres or a slight advantage to the air pistols. Of course with these examples of shorter barrels we're still looking at a minimum of about 8.5", and usually between 9" and 10", so not really very short. And the velocities involved are usually in the 480fps to 650fps range, with most of the pistols between 480 and 570fps. The rifles tend to be tuned a bit faster to keep the barrel time to a minimum. Shooting faster than these speeds tends to destroy accuracy. I imagine it must be a very different thing for bench rest, where much longer ranges are involved and therefore much higher velocities? So perhaps leading in the rifling quickly becomes problematic because of this higher velocity? Doing a bit of Googling it seems velocities are typically in the 850 and higher range, but I didn't search exhaustively. That alone would easily explain the need for constant cleaning. The higher the energy the more likelihood of leaving partially melted lead in the grooves.
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Absolutely, the difference in velocity between a match pistol and a benchrest rifle makes any comparison of barrel leading useless, IMO....
Bob
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Gerard,
LV class typically will shoot 8.4's at 795. (12fpe max)
HV class typically will shoot 10.3's up to 920, or 13.4's up to 815. (20fpe max)
Open class typically will shoot 16's or 18.1's between 850 and 935. (35fpe max)
With a 1:18 twist barrel you are spinning up the pellet to about 30,000ish rpm in 24 inches.
I would be willing to bet that I could get your pistol to shoot just as well without the stripper.
Mike
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These brakes (air stripper) can be custom tailored to meet your specific needs. ;)
http://www.blackrose-tactical.com/product-category/muzzle-brakes/ (http://www.blackrose-tactical.com/product-category/muzzle-brakes/)
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I have one on my TD257 because i knew i would be moving a lot of air while shooting cast bullets. My gun started out at 900 FPS with a 70-74 gr bullet. I also did it for LOOKS.
Now, i have NOT done any extensive research on the subject of whether it works BEST WITH and/or WITHOUT a stripper but my gun has been accurate in both configurations. A SHROUD/LDC is a stripper also. I don't think there is as much air coming out of the end of a SHROUD/LDC because its all either rerouted or deflected inside of multiple chambers. And everyone seems to NEED one of those and their guns produce great accuracy. And i'm sure the gun is just as accurate without.
The 1 thing i have noted/noticed with my TD257 and the HATSAN Air-Stripper is there is definitely a POI differencce with and without it on the gun. AND YES, IT TAKES SOME ADJUSTMENTS to get it right!
I would be nice to see some HS camera footage like shown above of WITH and WITHOUT as well as a well written/documented post showing results.
I elect BOB STERN.......lol (he is gonna kill me.....lol)
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hrvoje.... Those are muzzle brakes, NOT air strippers.... total different concept....
Cedric.... nomination respectfully declined.... :P
Bob
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The little bit of playing with them that I've done hasn't proved they did much for me. Perhaps better rifles, better shooter, better barrels, etc.
Whe I did think I got a positive result (not by much) I ended up making a "blank" stripper...same sweight, same length, same attachment, just drilled too large to really have any effect . TUrned out the same rifle seemed to shoot as well with the blank as the stripper. So I wrote it off to weight vs. barrel harmonics.
Only strippers that get my attention now also serve drinks.
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oh no you didnt just take it there :D
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oh no you didnt just take it there :D
;) ;D ;D ;D
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hrvoje.... Those are muzzle brakes, NOT air strippers.... total different concept....
Cedric.... nomination respectfully declined.... :P
Bob
Three or more bafles in muzzle brake not removing turbulent air from around the pellet ::)
tnx for declined ;)