I just got a leaking Challenger for free but would like to be able to get it up to hunting power. Can it be done and how? I was thinking dickering about with the hammer spring and possibly enlarging the transfer port. I don't know much about the gun but suspect its similar to the Disco so 900 fps should be doable. I don't care about loosing shot count, 20 - 30 or so per fill is fine with me. Any help is appreciated.
Crosman Challenger 2009, Can It Be Modded For 800 - 900 fps?
- Thread starter Dan25
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Based on your hunting application, 800fps yes with light pellets, 900 not reliably without possibly installing a regulator. Installing a P-ROD .08 TP whould give you a decent start with no other modifications necessary no need to mess around with the hammer spring. You are looking at around 700fps shooting 10.3s as the best reliable accurate set up without needing a regulator or worring about fliers or other problems. If you try to go higher then you will be asking for problems with unexplained fliers which you don't want when hunting and lose a lot of efficiency and the shots will have frequent erratic behavior requiring you to install a regulator then the onboard air gauge (manometer) won't be as functional as it should be and will only read the regulator pressure. It is also going to be LOUD and the way the barrel is set up in relation to the air cylinder, it will prevent a direct fit LDC from being mounted. The Maximus Hunter in 22 would be a better choice for hunting for a single shot or a Gamo Urban in 22 multi shot on sale at right now at PA there are more fitting tools for the intended use.
I recall in the quest of upping the power too much by trying TPs larger than .08 got unexplained fliers from time to time. Had not installed a regulator and would have been really annoyed had I did if after that, the fliers still remained so I decided not to and stuck with the .08TP because I especially wanted to preserve the function of the manometer as a check for any signs of leakage when not used.
PM'd You.
CA
I recall in the quest of upping the power too much by trying TPs larger than .08 got unexplained fliers from time to time. Had not installed a regulator and would have been really annoyed had I did if after that, the fliers still remained so I decided not to and stuck with the .08TP because I especially wanted to preserve the function of the manometer as a check for any signs of leakage when not used.
PM'd You.
CA
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Thanks for the information. Cant just sell it bc it would anger the giver who could have done that himself. I don't even have it in hand yet but was thinking it would be great for close range for doves, maybe a squirrel but mostly just plinking. I will try your P-ROD suggestion and mess around with other adjustments after making note of the factory settings so I can return if needed. I would be happy with heavies at 700. I have a Gen 1 Marauder in .25 with a SWAFA 10x for my more serious air gunning. I need to get the air tube honed as it keeps clipping O-rings then get a hammer debouncer from WAR and more tuning.
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At close range doves & squirrels only need about 6fpe at the muzzle, it should be accurate enough to do this as issued.
John
John
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And I might add that it will be significantly QUIETER at the factory set power level with TONS of shots to boot for a low low fill pressure!
It will shoot like a regulated target rifle when left alone as how it was meant to be from the factory.
CA
It will shoot like a regulated target rifle when left alone as how it was meant to be from the factory.
CA
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John, thanks for the info but the tree rats we have are large and very tough so I was wanting the highest power without killing accuracy. My RWS 34 in .22 shoots standard weight domes at about 670 fps and is enough but not excessive. I hate the thought of wounding one and having it suffer.
Coldair, quiet is not a problem. My buddy has a lathe and milling machine so a home made silencer is in planning. Im thinking aluminum ends, carbon fiber tube with M-rod type baffles machined out of some UHMW I have laying around. That or I might just buy factory Benji baffles. Air is not an issue. I have a buddy at the fire dept so I can get all the filtered 4,500 psi air I can shoot for free.
Coldair, quiet is not a problem. My buddy has a lathe and milling machine so a home made silencer is in planning. Im thinking aluminum ends, carbon fiber tube with M-rod type baffles machined out of some UHMW I have laying around. That or I might just buy factory Benji baffles. Air is not an issue. I have a buddy at the fire dept so I can get all the filtered 4,500 psi air I can shoot for free.
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I did this similar conversion last week by drilling out the transfer port to 5/64 in. Now yields approx 10 foot-pounds.
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That calculates very close to 0.08 recommended above. What velocity are you getting with what weight pellet? Are you planning on working with the power adjuster for more power? Im wanting to push this thing as hard as I can without loosing accuracy or getting flyers. I gotta get a scope, rings and the previous owner lost the tiny bbs that hold the cocking assembly together so Im going to be at least 2 to 3 weeks behind you. Above Coldair reports nearly 700 fps with 10.3 gr so that's what Im shooting for. Will definitely try various JSBs as they are my favorite brand but mail order only in my area. Keep me updated on your tuning progress and results. Thanks for the info.
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I just took it outside and shot two groups at 25 yards. Both groups were 10 shots. the group on the right was shot at 720 feet per second with an 8.2 grain pellet. The one on the left was with the power adjuster cranked all the way in with about an eighth of an inch left and it is averaging 803 foot per second. 9 out of the 10 shots fit under a nickel. They were shot quickly just off of a front bag and the pellet is not the most accurate it is the h & n sport flat nosed pellet. I am definitely not getting the flyers that were talked about. Trust me very little effort went into shooting these two groups. And these were the only two groups shot. The taking the gun apart and drilling out the transfer port whole process took about 25 minutes. Will go try some heavy hunting pellets. 
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Two groups with JSP heavy exacts 10.34 grain. 9 out of 10 under a dime at 600 fps. Then 4 under a dime at 665 fps. Ran out of pellets. Lol. Still 25 yards front bag only.
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Shawnlyndy Thanks for your reply and I want to thank all others for taking time to reply and assist me in my quest. That's what I like about this community. I am partial to JSB and will test 8.44 and 10.34 grain domes and some H & N Baracuda 10.65 domes. I have spent some time digging about the Crosman site and notice a great many Discovery parts are the same as in the Challenger. The valve is identical other than the cap and even the hammer spring has the same part number. I am wondering what's the inside diameter of the Discovery transfer port, above 0.08? Im unfamiliar with Discovery power outputs, but cant see any reason why the Challenger cant match it. The problem might be maintaining accuracy while getting so far away the velocity/power that the bbl. was designed to operate at. I know the gun is going to get a bit less than backyard friendly but I am planning a custom moderator.
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Don't overdo it in your quest for power because you will also run into problems with the AR style "T" charging handle springing back when taking your shots giving you blowby which will throw errant shots and if you lose those T handle retaining bbs (ball bearings) when it does (and IT WILL) fly open after the higher than recommended power level shots, you will have a non functional gun and have to order extra retaining bbs from Crosman. The only thing I can think of to not have that happen is to wrap a tight bungie cord around the rifle's T handle around the trigger guard after loading/cocking before taking every shot or forcefully holding it in somehow as you are taking each higher than recommended power shot to not have the T handle spring open. It doesn't seem like it can be engineered or modified to make it any stronger than it already is.
It simply can't take the higher than recommended power that is the other important reason you need to cap it off with a regulator.
i can see your quest of overdoing it with your comments about the discovery parts compatibility but in this case of the 2009 Challenger it is meant as a low velocity shooting entry level 10 meter PCP rifle. It was simply not designed to be hot rodded too much.
Making it shoot consistently and reliably without a regulator only requires the larger transfer port and factory spring adjustment for fine tuning over a chrony. Anything over .08 or the power level recommended may result in the T handle and ball bearings popping open when you shoot it. It may not do it immediately but eventually it will no longer handle the extra pressure because it will prematurely wear out to that point and keep popping open.
I suggest buying a Maximus Hunter if you need more power than was recommended because you WILL run into problems by trying to over do it.
CA
It simply can't take the higher than recommended power that is the other important reason you need to cap it off with a regulator.
i can see your quest of overdoing it with your comments about the discovery parts compatibility but in this case of the 2009 Challenger it is meant as a low velocity shooting entry level 10 meter PCP rifle. It was simply not designed to be hot rodded too much.
Making it shoot consistently and reliably without a regulator only requires the larger transfer port and factory spring adjustment for fine tuning over a chrony. Anything over .08 or the power level recommended may result in the T handle and ball bearings popping open when you shoot it. It may not do it immediately but eventually it will no longer handle the extra pressure because it will prematurely wear out to that point and keep popping open.
I suggest buying a Maximus Hunter if you need more power than was recommended because you WILL run into problems by trying to over do it.
CA
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The weakest link in your quest for power for the CH2009 is that darn T Handle. If it was a bolt action such as a Discovery or Maximus or a 1701p or 1720T or a P-Rod or Marauder then there wouldn't be anything to worry about regarding the bolt popping open when upping to higher power aside from a harder than normal cocking effort and I might add that if you put a heavier hammer spring then you may just be the one to pull the T handle out of the rifle just by cocking it due to the added force needed to pull it back.
Hopefully the previous owner hadn't tried to overdo it which may have been the reason he lost the bbs when the T handle sprung open with the higher than recommended power increase as he took the shot. Just like I said more than likely popped completely out of the gun losing the bbs.
A heavy hammer spring in the quest for more power would cause the shooter to pull the T handle completely out of the gun while cocking it.
Hopefully it isn't overly worn out just pray it isnt' to that point.
Get youself A LOT of spare T handle BBs!!!
CA
Hopefully the previous owner hadn't tried to overdo it which may have been the reason he lost the bbs when the T handle sprung open with the higher than recommended power increase as he took the shot. Just like I said more than likely popped completely out of the gun losing the bbs.
A heavy hammer spring in the quest for more power would cause the shooter to pull the T handle completely out of the gun while cocking it.
Hopefully it isn't overly worn out just pray it isnt' to that point.
Get youself A LOT of spare T handle BBs!!!
CA
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Shawnlyndy I hope you are paying attention to the consequences of trying to over do it. Just be gentle when cocking the gun so that T handle mechanism doesn't prematurely wear out. I would order some spare T handle BBs too just incase.
CA
CA
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Shawnlyndy also shoot it over the chrony using a steady firm rifle rest and just experiment and set the power at what is the most accurate velocity because you should easily get one hole groups the size of 1/4" or less (25 caliber pellet hole size) at 25 yards 10 shot groups when set correctly. Make sure you shoot it for groups on paper targets as you are running it over the chrony so you know what velocity will give you the tightest groups. Upping the power too much just to get a higher velocity may not get the best one hole groupings in the Challenger FYI. I know you are a target shooter so don't focus on power then you will achieve the best consistant accuracy out of your gun.
CA
CA
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As stated I got the gun without the BBs so I have been unable to work the action. Are the BBs the locking device for the action or is it friction of the bolt probe O-ring or a combination of both? I know many German HK guns have roller locked bolts. Still, as explained above, I believe additional O-ring(s) on the probe just might provide enough friction to hold the action closed. This allowing higher power tune and avoiding air leakage and loss of accuracy. Just theory at this point. Yes this is a work around and the proper way is a locked action like the Discovery. Just trying to get accurate, reliable 12 - 15 foot pounds.
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The bbs are the locking device to keep the bolt closed and I am not sure if the extra o-ring modification would help minimize the chance of the T handle popping out given the extra pressure past 11fpe and besides it WILL eventually wear out with the constant rubbing and friction every time you load your pellet anyway then you have your problem and just lost your bbs again but you won't know when the extra o-ring will wear out (any time?) it would be a bummer for me when hunting and the gun quits after springing its bbs in the middle of a hunt. If I were an engineer and had the equipment to take on a project such as yours then I would consider modifying it to use larger bbs for more tension instead but it is JMHO.
I think adding additional o-rings to the bolt probe will be rather inconvienient because it will greatly increase the effort to close the bolt/T handle.
The larger bbs mod would probably keep the bolt smoother loading.
Want more traction get bigger tires!
CA
I think adding additional o-rings to the bolt probe will be rather inconvienient because it will greatly increase the effort to close the bolt/T handle.
The larger bbs mod would probably keep the bolt smoother loading.
Want more traction get bigger tires!
CA
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Like I said at this point its theory. I still don't know if the tiny O-ring at the breech is the locking mechanism or is it the BBs at the rear or both? Got on the phone with my machinist buddy and he is willing to participate in this but at his own schedule and its deer hunting here. Granted the additional rings on the probe will add to effort to cock the gun but then wouldn't a heavier spring or more spring tension, aka cranking down, also do the same? My thinking is that same initial effort would also be that little extra that would hold the action closed when it would have opened causing the flyers above mentioned. This can be tuned by the number of O-rings, dept of the groves in which they sit and the durometer of the O-rings. Welcome to tuning PCP air guns. We are all working on theory at this point and might wait on results then evaluate them and proceed as indicated. As I have stated if all I can get is 10 or 11 fpe then I'm all happy considering my cost at that point. I just thought it might be interesting to see if some innovation could add a few foot pounds of energy over just boring out the transfer and twisting down on the hammer spring. Who knows if you don't give it a go. Considering the weakness of the action a I would be surprised if I could get more than and additional 2 foot pounds over established and not surprised if I get anything.
We air gunners love to tinker, its our way. I would have never spent to buy this gun but it was given to me and Im going to see what I can make of it. It may be a fail and return it to original and if it is so be it.
But then the next mod. Considering this thing is a basically a match grade Discovery and there are a bunch of Discovery owners who have highly modified guns and lots of stock parts gathering dust, there should be plenty of Disco bolt groups sitting around. How about getting them cheap and mating them to the Challenger bbl. and have the best of both worlds. There I go thinking about tinkering about. I wonder if it could be done?...........
We air gunners love to tinker, its our way. I would have never spent to buy this gun but it was given to me and Im going to see what I can make of it. It may be a fail and return it to original and if it is so be it.
But then the next mod. Considering this thing is a basically a match grade Discovery and there are a bunch of Discovery owners who have highly modified guns and lots of stock parts gathering dust, there should be plenty of Disco bolt groups sitting around. How about getting them cheap and mating them to the Challenger bbl. and have the best of both worlds. There I go thinking about tinkering about. I wonder if it could be done?...........
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JMHO if a heavier hammer spring is used then the increased effort to cock and having to pull the T handle harder could by itself cause the bbs to come flying out. I would sure be interested in how this one turns out and how it can reliably be bumped to more than 12fpe without any problems.
Another bright idea from my non airgun design engineering mind is to design a latching device mounted to the rear dovetail to flip down to force the T handle to remain shut while firing. You just flip it up to cock and load then gun then flip it down after you close the bolt home before you fire. I would not mess with the hammer spring because you should theoretically get above 12fpe just by openning the TP larger than .080 unregulated and up to .089 (when using a regulator) I believe anything larger than that will only waste air and give you a terrible shot string. Bear in mind that the shot to shot consistency will not be as good going past 11fpe and the shot curve will become more pronounced the more higher power you try to get above that level negating the benefits of a good naturally self regulated target rifle. For me accuracy and non regulated consistency trumps excessive power.
CA
Another bright idea from my non airgun design engineering mind is to design a latching device mounted to the rear dovetail to flip down to force the T handle to remain shut while firing. You just flip it up to cock and load then gun then flip it down after you close the bolt home before you fire. I would not mess with the hammer spring because you should theoretically get above 12fpe just by openning the TP larger than .080 unregulated and up to .089 (when using a regulator) I believe anything larger than that will only waste air and give you a terrible shot string. Bear in mind that the shot to shot consistency will not be as good going past 11fpe and the shot curve will become more pronounced the more higher power you try to get above that level negating the benefits of a good naturally self regulated target rifle. For me accuracy and non regulated consistency trumps excessive power.
CA
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