GTA
General Discussion To Gateway To Airguns => Airgun Gate => : Schapper March 25, 2010, 03:49:18 PM
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My best friend has an R10 that "someone" had broken the stock in half right were you wrap your shooting hand around. I glued the stock back together for him and while it looks nasty (for now until I can get it to shoot properly) it seems to be straight enough judging by all the break lines matching up and all.
He has recently bought a Gamo Silent Cat and one for me as a gift with the cool idea of us sitting on his porch shooting pest birds from around his bird feeder. (in return for him buying me the gun I sent his to Gene to have a tune performed and GRT111 installed. Yes, they both have metal triggers) He bought these because he said his old R10 had started to shoot wild patterns. I've been lurking around here for a few weeks trying to find as much info as possible before going the newb route and just asking for info, but there is sooo much info all over and the terminology makes my head spin at times. I was hoping that it was a loose stock causing his original problem and after getting the stock back together and tightened securely we installed the scope that came with his Whisper since I wanted to try to deduct the scope he had originally causing the bad patterns out of the equation. The Whisper scope was already in the mounts since we had to take it off to send to Gene and we just screwed the mounts to the rail on the R10 and the thing shoots at least 12 inches high at 30 yards with the scope adjusted all the way out. At ten yards it make a nice pattern midway up the target if I aim at the bottom of the target, but at 30 yrds I have to aim at least 12 inches low and the patten is all over the place.
I've read about using shims to physically move the scope into adjustable range, but thought you guys may have other suggestions as to what may be causing the problem with not being able to get the gun to even hit a target.
I appreciate y'alls site and hopefully one day will be able to understand everything you guys are talking about. lol
Thanks!!
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WELCOME to the GTA Forums Schapper !
The GTA is the BEST Air Gun Forum and Family on the Internet ! ! !
And, IT'S A GREAT PLACE TO BE !!!!
Now you didn't say what caused the stock to break, so it may have a bent barrel ?
If not, you may need an adjustable scope mount ! I doubt that you can shim the scope that much.
I hope this helps, and I hope to see you here often !
Bill
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Thanks Big_Bill! I can tell that you all are a tight-knit group and it's been a pleasure to read all of y'alls posts.
Remember in Family Circus when the Mom would ask "Who did this" and all the kids would answer "nobody" and then they would show a ghost named "nobody"? Well that's kind of the deal with who broke the stock. Nobody seems to have done it. lol So there's no telling how it got broken.
I looked down the barrel and it appears to be perfect, but I'm not that familiar with these things so looks could be misleading, I guess, but it looks perfect to me.
Thanks for the advice. I've never run across an adjustable mount in all my looking around, but then again I was never actually looking for one. I'll have to look into that.
If anyone has anymore ideas please chime in!
Thanks!
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Do you have pictures of the mounting? Could it possibly be a droop mount on backwards? I use adjustable mounts on my springers to tackle these problems.
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it sounds like the stock broke cause the barrel slammed shut and bent it up. thats an easy fix. take it off and put it in a padded vice. use a pipe and pad where it contacts the barrel and tweak it down alittle. it dosnt take much. i did this with my b26 and its pefect now
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Run a square down the barrel to see what your working with first. Ed
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I second what Tom said, the barrel slammed shut and broke the stock + bent the barrel upwards. There's a tool-less method to get it straight too - remove the scope and mounts, remove from the stock and cock it while the action is upside down on the floor (carpeted!) after the cock cycle is sone keep bending the barrel towards the action. It requires some force, but less than you think. Make sure the safety is on and maybe rig the trigger so there is no chance of firing.
Hope this helps
Chris
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Wow guys, thanks! The mounts are the cheapo ones that came with the whisper so no, not drooper mounts.
I will put a straight edge on it to see what's up with it being bent or not before trying anything. I don't have the gun here right now to look at it, but wouldn't breaking it over past it's stop bend the cocking linkage, or rail, or block...whatever it's called by pushing it into the piston top that is being stopped by the trigger? I don't want to mess up the seal where the barrel and receiver meet and if something bends besides the barrel it seems this could happen. Not trying to be hard-headed...I'm just ignorant about these so forgive my ignorance.
I've never had it happen, but how would a barrel snap closed that hard to actually bend the barrel? By the piston not being fully engaged in the trigger and the barrel being let go of? How many ft. pounds are on one of these springs anyway?
And if this is what has happened does it usually bend at the receiver end or can it bend somewhere in the middle when this happens? I ask because I want to learn, but also because I'll have to explain to my buddy why I'm prying on his high dollar rifle barrel. lol
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If the gun is shooting that high it almost certainly been slam fired. Yes, the spring does have considerable power behind it. Add to that the momentum of the two halves of the gun swinging violently around and you get a lot of energy generated. More than enough to break the stock and bend the barrel upwards, with enough energy left over to do considerable damage to you if the gun flies apart in your hand. Imagine the stock coming apart and the barrel continuing in its arc right towards your face. This has happened in the past.
Theres enough energy released that it can also do more than bend the barrel and break the stock. Slamfires can damage just about any part of the gun. The yoke on the barrel where it attaches to the breech block can get tweaked, screws can get bent or broken, attachment points for everything can get bent, the mainspring can break, etc etc etc.....any one of which in combination with a bent barrel will make the gun shoot all over the place. If its that bad it probably needs professional help.
Slamfires do happen a lot, for various reasons. Improper handling is the main reason. Cocking the gun with a finger in the trigger guard, not holding the barrel while its open, or not fully cocking the gun and releasing the barrel. Weihrauch guns with the Rekord trigger are prone to slamfires when the trigger is tampered with by someone who doesn't know how to make adjustments properly. If its set too light or of the lock tabs are removed or bent the trigger can release without warning.
Don't try bending the barrel as described by cocking it then bendig it further. You'll almost certainly do more damage to the gun. The cocking link, tube, breech block pivots, trigger and just about everything else can bend or distort.
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remove the barrel like i said. its the easiest way to fix t
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Welcome. Many of us have had poor results with the scopes Gamo ships, they seem to break after a little use. If the open sights are there, use a rest and sight in at 20 yds or so, if you have good pattern, then think mounts and scopes. I would suggest that the Wal Mart Centerpoints are pretty decent, and get a mount that has a stop pin. Clamp her down well, clean all the screws and apply blue loctite. Dano once advised me to put some grit (as from a grinding wheel) along the rails before clamping. My own experience trying to get a Whisper to pattern was a bad one, though. I hope the new owner had more luck than I did.
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Thanks for taking the time to explain all that, arathol. Makes complete sense now.
I WISH he had kept the open sights for the gun, but they disappeared long ago when he mounted the scope. He claims the gun was shooting erratically before the stock broke so I was hoping it was the scope he had on there at the time or loose stock screws causing this and that putting on the 2 week old Gamo scope and repairing the stock would do the trick. I'm sure one of his boys slam-fired the gun after he had given up on it shooting straight again and moved on to other hobbies.
Just reading about the R10 got me excited though as it's apparently a high quality gun (especially compared to the new Gamo's) and I dreamed of making it fire true again with little effort after researching here for so long. I remember knocking a starling off of a fence post at 50 yards (even correcting for a slight breeze) when that gun was brand new 20 years ago!
I guess the answer to my question about where the barrel is bent (and where to "unbend" it) is what using the straight edge is for. DUH, just figured that one out. I just don't want to make a wavy barrel in the end. lol I told my friend about what y'all said about the possible outcomes of the barrel slamming shut like that and he was very impressed with y'alls knowledge and said (thank goodness) "Ah, I'm not really worried about it" when I told him what I might have to do to straighten the barrel out...which I guess will be the straight-edge, vice and pipe method.
Thanks so much for all of your help and knowledge and welcomes! This place is awesome and has given me somehthing to look forward to learning more about and something to keep me out of trouble with at night.
However, now those pesky skunks will be the ones worrying when the Sun sets. lol
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Schapper, the barrel is most likely bent where it attaches to the breech block - the rectangular piece that pivots. The barrel is still straight past that point. Bending it down won't make it wavy, you'll bend at the weakest point which is where it enters the breech block. Also, it not necessarely had to be fired while open, it could have slipped out of somebody's hand while cocking, that's how my B26 got messed up, it was not a huge slam, but enough to crack the stock and bend the barrel up. And I am sticking to my method on making it straight - it does NOT take a great force to fix, not enough to damage other part like the linkage or piston seal.
Hope this helps
Chris
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Oh, OK. Thanks Chris, that does help me to now visualize were the bend would happen the easiest. To tell you the truth, since I don't have the gun here and can't hold it while reading y'alls posts , it's been hard for me to imagine where the bend might be because I wasn't visualizing the breech block...only the round barrel and thinking "Hell, it could have bent anywhere and just how could that happen?" Just visualizing the round barrel, I was imagining it would have bent in the middle because that's where most of the force would be exerted since the inertia would be coming from both ends...if that makes sense. lol
I'm getting excited to get my hands back on this beauty!!
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If you are basing the force needed to bend the barrel on one experience with a cheap Chinese rifle, thats a bad example. The barrels on Weihrauch guns are of far better quality and take more than a little effort to bend. For example, I had to take the droop out of an HW35 some time ago. After securing the breech block a 4 foot pipe was neccesary to exert enough force to bend the 19" barrel about 1/8". Doing it by trying to force the barrel against the other parts of the rifle can damage the yoke, breech pivot, the cocking limkage, especially the end where it engages the piston, possibly the trigger if the latch rod pushes to hard on the sear.
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Wow, that's great info on different methods of doing things on different brands of guns, arathol. That brings up another thing that came to mind...barrel droop since I'm basically trying to "undroop" a barrel...or am I?
The tool on CDT's site shows that you put the eye bolt in the middle of the barrel. Does this mean most barrels are drooping in the middle? Or are they drooping at the breech block and this tool will correct one that is bent at the breech block if the breech block was in the support at one end? The Doc. doesn't specify putting the breech block in one of the supports so it's kind of confusing as to wear the droop is occuring.
Thanks!
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your problem isnt barrel droop. its bent up from misuse. bendng it the way i described is the best method
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Thanks Tom, that's what I'm gonna try. I guess all this talk about barrels being bent brought to mind the droop issue since I never really understood it. I was thinking I was gonna be doing the opposite of correcting droop since I will be bending the barrel down instead of up. Now knowing to put the breech block in the vise has cleared up a lot for me.
The term "droop" always confused me, but I just found this by using this new-fangled site called Google. lol http://www.pyramydair.com/blog/2006/01/barrel-droop.html
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its usualy the breech block is drilled off center. or in the lockup
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http://www.pyramydair.com/blog/2008/07/straightening-barrels.html
Me and my cheap Chinese rifle concur though... no more posts on this matter