GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: CitySniper on February 06, 2013, 10:04:19 PM
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I stole this picture and idea from Motorhead on the Marauder forums...(think he is over here too?) But Basically the holes on the stock air stripper have been enlarged from the factory 1/8... to.. 3/16 to make it more efficient... ;) 8)
BEFORE:
(http://img.photobucket.com/albums/v722/wtani/IMG_7372.jpg)
AFTER:
(http://i1320.photobucket.com/albums/u532/scott_schneider1/IMG_1185_zps171026af.jpg)
I did this modification today on my .22 marauder already depinged..and shooting 35 fpe...I can say it really works! Just a touch quieter , especially can tell the difference in the lower psi. range where the gun normally got louder...sounds more consistently even, very pleasant to shoot.
here is a link to the thread: http://marauderairrifle.com/forum/viewtopic.php?f=24&t=5475 (http://marauderairrifle.com/forum/viewtopic.php?f=24&t=5475)
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Yup ... solid mod to make that does indeed quiet report further ;)
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How is the air stripper attached to the barrel ? Is it a friction fit? Can it be tapped off of the barrel ? I want to remove it to put my shroud extension on the breach end of the barrel.
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How is the air stripper attached to the barrel ? Is it a friction fit? Can it be tapped off of the barrel ? I want to remove it to put my shroud extension on the breach end of the barrel.
It is press Fit on....I used a Cresent wrench behind it to tap it off..(comes off easily) then Did my drilling/sanding and reinstalled.
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How is the air stripper attached to the barrel ? Is it a friction fit? Can it be tapped off of the barrel ? I want to remove it to put my shroud extension on the breach end of the barrel.
It is press Fit on....I used a Cresent wrench behind it to tap it off..(comes off easily) then Did my drilling/sanding and reinstalled.
Or a pin punch / nail threw the holes and twist it off.
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Thanks
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Okay so you know I had to run the gun across the chrony to see if I lost power.... and guess what? I gained about 10-16 FPS on average throughout my shot string! ;D :o
Old Shot String, Before Air Stripper Mod, 2,900 psi. Fill, using 21.30 Grain 5.53mm Baracuda Pellets
1 813.00 847.30 849.70 821.90
2 817.70 846.60 850.00 818.80
3 818.60 848.20 844.60 815.10
4 819.80 848.90 839.80 810.50
5 838.50 853.00 837.70
6 823.10 849.80 837.30
7 828.80 861.80 839.40
8 828.40 844.40 826.60
9 834.70 854.90 830.70
10 838.70 852.00 824.00 Max Fpe 35.136
New Shot String, after Air Stripper Mod, Same Pellets and Tune 3,000psi. Fill
1 815.90 864.80 862.70 826.60
2 824.80 872.60 862.50 825.20
3 811.50 862.80 855.70 817.00
4 827.70 872.50 855.80 813.10
5 839.60 868.70 851.80 800.90
6 845.40 869.10 846.70
7 850.30 871.30 841.60
8 854.50 871.40 838.70
9 859.30 873.50 838.50
10 858.90 874.70 824.30 Max Fpe 36.195
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Yep! Verified twice, with three different pellets. My guess is the air is more stable near the muzzle now allowing a bit more speed without more noise. Same thing happens on Powder burners when they use a suppressor their muzzle velocity goes up.
Like Motorheads' picture I made sure to also angle the hole like a tear drop to allow as much air back into the shroud as possible. Once the shape is there.. use sand paper, or a dremel to smooth and debur just like you would do on cylinder heads on a car to get better airflow..
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Awesome!!! Thanks for posting. I'll be doing that the first day with the Mrod
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Did not take any pictures ... :P ( Will take some ASAP and share )
But taken the IMPROVED air stripper even further by enlarging the bore exit hole to 5/16" and inserting a short section of K&S 5/16" O.D x .029" wall brass tubing ( I.D. @ .254" ) with end facing muzzle sharpened into a cone. A TRUE AIR STRIPPER NOW.
This further splits the air leaving muzzle making the factory stripper even more effective.
* Guns report even LESS !
As a reference, here another version I did to a Crosman shrouded NP springer.
* You can see the brass tube looking threw the vent holes.
(http://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=36735.0;attach=48462;image)
Ideally you want bore tube to be @ mid hole as viewed from the side so air thats split away from bore can readily flow out the vent holes into shroud.
here an Air Arms stripper further elaborating on the concept of splitting the air to maximize shroud filling.
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That is called "Free bore boost". Very interesting phenomenon.
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Okay so you know I had to run the gun across the chrony to see if I lost power.... and guess what? I gained about 10-16 FPS on average throughout my shot string! ;D :o
Old Shot String, Before Air Stripper Mod, 2,900 psi. Fill, using 21.30 Grain 5.53mm Baracuda Pellets
1 813.00 847.30 849.70 821.90
2 817.70 846.60 850.00 818.80
3 818.60 848.20 844.60 815.10
4 819.80 848.90 839.80 810.50
5 838.50 853.00 837.70
6 823.10 849.80 837.30
7 828.80 861.80 839.40
8 828.40 844.40 826.60
9 834.70 854.90 830.70
10 838.70 852.00 824.00 Max Fpe 35.136
New Shot String, after Air Stripper Mod, Same Pellets and Tune 3,000psi. Fill
1 815.90 864.80 862.70 826.60
2 824.80 872.60 862.50 825.20
3 811.50 862.80 855.70 817.00
4 827.70 872.50 855.80 813.10
5 839.60 868.70 851.80 800.90
6 845.40 869.10 846.70
7 850.30 871.30 841.60
8 854.50 871.40 838.70
9 859.30 873.50 838.50
10 858.90 874.70 824.30 Max Fpe 36.195
Hey C.S. just curious that is a really sweet shot string, have you done any custom work to your m-rod?
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Thanx Pyro...Nope all the internal parts are stock. But the gun has been completely taken apart cleaned /lubed and put back together..Oh yeah only part not factory is the breech O-ring...I got an upgraded one from Mac-1. The settings are basically maxed out and I am using the heaviest most accurate pellets the gun likes.
P.S. from what I am hearing on the Marauder Forum... This Air Stripper modification is suppose to be more noticeable on the already louder .25 Marauder. Probably benefits more from it because it uses more air to shoot those heavy pellets.
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The barrel is larger on the .25 and there is less room in the shroud to disipate the pressure wave.
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Thanx Pyro...Nope all the internal parts are stock. But the gun has been completely taken apart cleaned /lubed and put back together..Oh yeah only part not factory is the breech O-ring...I got an upgraded one from Mac-1. The settings are basically maxed out and I am using the heaviest most accurate pellets the gun likes.
P.S. from what I am hearing on the Marauder Forum... This Air Stripper modification is suppose to be more noticeable on the already louder .25 Marauder. Probably benefits more from it because it uses more air to shoot those heavy pellets.
Nice ;D ;D, I read your first post again and noticed that you mentioned your M-rod has a depinger installed, which partly explains that sexy shot string 8).
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Yeah, The depinger does quiet the PING and is just some Vinyl tubing rolled up stuffed half way down the airtube and if anything that is costing me 1-2 shots by taking up airspace. I have had my .22 Marauder like 3 years now and it keeps getting better, which keeps me away from buying the .25 caliber.
But I still want one..I honestly do not need the extra power though
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Hi
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3mm thick felt is the material that some commercial LDCs use. You need something in there to hold it in place though, hair curlers are used in Weihrauch unit. Then again, if you go that route you could just use washers for baffles and free up some volume inside the shroud.
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Dead Nuts...to answer your question real quick and without getting this thread locked. I will say Yes, and I suggest you do a search on the forum marauderairrifle.com for Mr. clean magic eraser ;)
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Thanks and not trying to get the thread locked!!
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No Problem...I would have given more detail, But I know how that subject is handled. This air stripper mod technically is not adding any additional parts to the gun to make it quieter.
I also should have put a big WARNING "try at own risk" LOL because some people just might mess up their guns, (like trying to drill with it still on the barrel) and nick the crown ...haha
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Poor picture, but you get the general idea.
Some serious de-burring in order here and some details to getting flow paths cleaned up ;)
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Poor picture, but you get the general idea.
Some serious de-burring in order here and some details to getting flow paths cleaned up ;)
Nice....Some details on the brass insert please. K&S 5/16" O.D x .029" wall brass tubing ( I.D. @ .254" )
When I go into home depot where would I find it?..... Did you use epoxy to secure it or press fit?
I have so many question...did your accuracy increase?... and have you noticed an increase in power as well?
worst case scenario If I mess it up is a few buck from crosman to replace and start over...
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I am an avid hobbyist in R/C boats and the K&S brass more likely to be found in a hobby shop.
You should be able to find Thin Wall K&S brass, but the .029" wall 5/16" is a bit hard to find in most HS's.
You could really use about any type rigid hard plastic or metal tubing that would allow you to taper one end for peeling away the air at muzzle end. ( just make sure the I.D. hole has @ .030" greater diameter than caliber barrel it modified for and hole stays concentric )
I try and keep drilled/reamed holes an interference fit so all stays square and true for accuracy of alignment and easy take apart/assembly for the R&D process.
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Yep...before I left the on on my search I googled it and saw some hobby shops pop up..... After going to home depot, and lowes and them both not knowing or having it I went to a hobby store down the street...
Asked for brass tubing...he right away said ,make a left then a left....and I had an instant selection. I did end up finding a k&S 5/16 x.014 thickness like two feet long...for like 8 bucks. I did not buy it yet because I wanted to come ask you is that was too thin? But from your last response that should work okay...boy that stuff is hard to track down
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Yea the thin will work, but you DO NOT want the 5/16" O.D. because the I.D will be larger.
TO Recoup .... Size the tube you fit based upon CALIBER of pellet passing within it. Or just go bigger and cover a couple calibers ?
.177 use the 7/32 I.D. & .22 the 1/4" I.D. with the .25 cal in 9/32" I.D.
* Got calipers take em with you !
Note:
CLOSER the I.D. is matched to caliber, more effective stripper will be ;)
K&S brass also comes in 1 foot lengths in counter displays ... may inquire if ya don't want 3 feet ?
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After coming home, shooting my gun and just pondering. I have made up my mind, to just leave well enough alone for now. The gun has already picked up some feet per second and I accomplished the original goal of making it quieter.
Soooo If I plan on adding the brass cone in the future...I am gonna just buy a new air stripper from crosman and Mod that one so that I can keep the one I have modded right now.
thanx for all your help Motorhead!!
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I have a similiar problem finding the right size tube that can be finished down to a fine sharp edge. Using a section from a broken graphite fishing rod for now, which can't without cracking. It is for a prod, so makes fitting even more fun. Going to try for two small baffles in the front of this. WIP
(http://www.joefishin.com/ProdAS.jpg)
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well, seems like a nice mod, and i could see people buying these things if they didn't wanna try to do this themselves.
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Here's an idea..
Hatsan air stripper.. Thread the barrel to 1/2 unf
Gaska 3" shroud extension for the added length (cut baffles to length)
Turn the outside or add material as needed and cut a groove for the o-ring
http://www.airgundepot.com/hatsan-air-stripper-22-caliber-ha90105.html (http://www.airgundepot.com/hatsan-air-stripper-22-caliber-ha90105.html)
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Ok just did mine, but I drilled straight into the hole ( 3/16 ) then to get the aero dynamics I use my sleeting iron/ wood burner. It did a great job. Just stick the pointed end in the hole a drag back a few times. Plus there was barely any sanding needed
After looking at the baffles I was thinking why not try so 1/8 holes in them, or is that a bad idea -- anyone!
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Cool, Did you notice a difference in sound? As far as the baffles... I think Crosman already got it right in that department, The only better baffle design would be the cone type
Plus some guys tried it already a couple years back on the Marauder Forums..