The Accurate Reloading Forums THE ACCURATE RELOADING.COM FORUMS Guns, Politics, Gunsmithing & Reloading Gunsmithing Unable to boresight...Warped Barrel??Go | New | Find | Notify | Tools | Reply | |
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I have an old 308 built on a VZ24. It was out of my stables for a few years. I have no idea how the other party treated it. When I got it back it shot all over the place! So it sat in safe for several years. I had it pillar bedded and slapped a Leupy on it and went to the range to see what was going on. Rifle in vise, bolt removed and bore centered on target, scope waaaaaaaaaaaay the FK off to the right. Cranking the windage all the way to the stop only got the scope within 3ft of the boresight. I know for fact the mounts are perfectly centered. What could possibly cause this condition? Time for a new barrel? We Band of Bubbas N.R.A Life Member TDR Cummins Power All The Way Certified member of the Whompers Club | ||
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Did you free float the barrel? Too much pressure on against the right hand side of the barrel will cause that. Pull the bolt, clean the bore and put an unprimed case in the chamber and peer down the bore from the muzzle end to check the diffraction rings. If the barrel is out of whack you will spot it immediately by the lack of concentricity of the rings. And how do you know the mounts are perfectly centered? _______________________________________________________________________________ This is my rifle, there are many like it but this one is mine. My rifle is my best friend, it is my life. | |||
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Centered to what? What was your bore sighting process? A crooked barrel or crooked bore can cause a lot of issues. So can a loose barrel. | |||
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Shoot it, 25 yds will tell if all adjustment is used up. The mounts may have been bent. There are rings you can use on the scope to correct mis alignment. | |||
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Barrel is free floated and tight in action. My first attempt at boresighting is usually at 50yds. With the rifle in a shooting vise I remove the bolt and look through the bore at the target. Making small adjustments to the vise-it has locator screws, until the target is centered in bore. I then look through the scope to see if I am looking at the same target. I like a wide target back with only one target in place, no chance of mistaking a different target. All I saw was black. So I cranked the dial until I was close to the target-as close as I could get and touched off a round. Not even on the black backing, nowhere within 4ft! I previously had a windage adjustable rear mount. In an attempt to standardize many of my rifles I had installed Leupy QR mounts-the post and cam lock. Perhaps I need to revert to an adjustable windage rear mount. We Band of Bubbas N.R.A Life Member TDR Cummins Power All The Way Certified member of the Whompers Club | |||
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I was going to say get a pair of windage adjustable mounts. I have run across some scopes that run out of adjustment,one was on a new Browning model B-78. The scope was a Leupold 6.5x20x50. | |||
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We had a barrel press to straighten barrels. I would zero the scope so the crosshairs are back to the center of adjustment and then press the barrel. This was a common with cheap 22 LR and other new factory rifles. Never tell anyone to bend their barrel. It needs to be straighten. If this is a hunting rifle and you know that the mounts are on center than press the barrel. I found that different brands of barrels appear to have different alloys. Some bend easy and then some are more like spring steel. Heattreatment will very also. Take it to a gunsmith that has experience and a barrel press. I learned this from an old gunsmith that I worked for years ago. His saying to me was "kid that barrel is like looking into a goats ass". All it does is put out little pills!! Straighten out the wrinkles. | |||
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You say, it is shooting all over the place. Does this mean, it is's just not shooting where you want it? Making sure it shoots near where it's pointed should have been done before bedding it. If it shoots a group, even way off somewhere the scope can be moved with adjustable mounts. If it don't shoot a group, it ain't the scopes fault. I bet Les's plan will work if it does shoot a group. Kenny | |||
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It may have always been shooting off and adjusted back by the windage base. Most likely cause is that one base is off center or, if one piece, it is out of line. This isn't uncommon, even on factory rifles. | |||
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I'm just a rank amatuer here but if it is 4 feet off at 50 yards even I should be able to just look at the firearm and see a bent barrel or a crooked scope with the naked eye. Take a long hard look at it first. | |||
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Considering the fact that 0.005" mis-alignment will put the bullet off 1" at 100 yds, it doesn't take much to mess things up. BUT...you really need to be more precise in your description... What did the gun shot BEFORE you turned it loose... Is the bore full of garbage or did you clean it... Is your ammo accurate or just some old krap you want to use up... Did you check the scope, rings, bases, barrel fitment, stock fitment??? You can tweak the receiver and cause a mess just as well as bending the barrel. If the rifle was indeed 4 ft off at 50 yards then you should be able to SEE that amount of mis-alignment in the components...were talking about somewhere in the neighborhood of 1/8" and if you can't take that amount out by scope adjustments then you have problems in the scope or who know where else. You need to start at the beginning and work through each aspect ONE AT A TIME...and I would start with cleaning the bore, then checking if the barrel is bent, buy a box of Rem ammo...THEN check the scope...swap in one you KNOW isn't screwed up internally... I've had the same problems with several rifles...barrel OR receiver threads cut slightly off center, scope base holes not in line or bases holes drilled slightly off center. Some problems fix easily, some need workarounds...it's just nuts and bolts and a systematic approach to solving the problem. If this rifle shot well before and doesn't now then something like a bent barrel might have happened...**it happens and people are...what they are...that's why I DON'T EVER lend my good shooters, not to anyone and that includes family members, I built them each a rifle and I will fix it, if it's needed or GIVE them another in exchange, but I DON'T LEND...I have 3-4 military rifles I let go out, but whoever borrows them uses their OWN scopes and FACTORY ammo. Let us know what you find. Luck | |||
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I didn't lend.....I sold and purchased two years later. It used to shoot ragged holes at 200yds. The bore was cleaned thoroughly and I was using Fed Gold Metal 168- a load it used to love. I plan on getting rid of the Leupy QD mounts currently installed and revert to dovetail front and windage rear like it had before I sold it. If I can't make it work then I'll let ya'll know. We Band of Bubbas N.R.A Life Member TDR Cummins Power All The Way Certified member of the Whompers Club | |||
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I would examine the muzzle real close looking for anything that looks out of the ordinary. Occasionally a bulge right at the crown can be difficult to detect unless viewing in a strong light at arms length. A slight bulge there will send bullets flying off course. _______________________________________________________________________________ This is my rifle, there are many like it but this one is mine. My rifle is my best friend, it is my life. | |||
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Crown is sharp. We Band of Bubbas N.R.A Life Member TDR Cummins Power All The Way Certified member of the Whompers Club | |||
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Is it grouping at all?? Even if it's shooting 4 ft off and still groups that might eliminate all but a bent barrel or messed up scope. I have a very old Weaver K4 that won't stay set no matter HOW much windage I put in...the group moves some amount, but not what you would expect by the scale marks and stays put for 3-8 shots then it jumps back about 12" right at 100 yd and stays there. Elevation is OK, but because it's old and steel and still works after a fashion and I don't want to loose it. The last time I sent a scope to Weaver they just sent me back a new, updated one. I stick it on slug shotguns and just aim a bit left...works great that way. Gotta be a bent barrel...maybe in shipment... or bad scope. Really got me scratching my bald spot.   Luck | |||
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If the barrel is bent, the bend location is most likely between the muzzle and tip of the fore end. Use a straight edge to determine. As someone else stated, a 4 foot deviation from bore centerline should be very obvious. Also check the air gaps between the barrel and stock. Are both left and right sides identical? If the barrel had been damaged they may not be. Do you have a cleaning rod approximately .30"? if so that should detect a bend in the barrel. Also, I recommend trying a different scope. There may be a problem internally with the lenses. After all that, I'd say you're in the market for a new barrel. Best of luck. | |||
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Several things come to mind: 1. Is the action itself binding, its not always the barrel, if you have side pressure on the tang then you get that effect..cutting wood out of barrel channel should never be done until you know the action is clear.. 2. You may very well need to surface grind the action. 3. If not surface grind the action then perhaps you can shim the bases until it comes to bore sight. 4. check all the screws and be sure they are tight.. I doubt that bore is warped but it may have been screwed in at an angle, it does not take much to get everything out of wack.. Its and investigation, and you have to approach it one thing at a time...Use the bore sighted in all these efforts. sometime its best to just toss it and start over with another gun.  Ray Atkinson Atkinson Hunting Adventures 10 Ward Lane, Filer, Idaho, 83328 208-731-4120 rayatkinsonhunting@gmail.com | |||
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If you decide to toss it as Atkinson suggests please record my mailing address so you can toss it my way. I think the scope and mount is suspect. If it shot great before, it will again once you find the culprit. | |||
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Can you post a pic of the rifle.jc | |||
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Went back to a one piece mount and Voila! Shoots like it used to! What was I thinking?!! We Band of Bubbas N.R.A Life Member TDR Cummins Power All The Way Certified member of the Whompers Club | |||
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and the one piece mount changed what? the front and rear rings are still in the same relative position to the bore because the mount(s) regardless of being one piece or two is still going in the same holes. Mike Legistine actu quod scripsi? Never under estimate the internet community's ability to reply to your post with their personal rant about their tangentially related, single occurrence issue.  What I have learned on AR, since 2001: 1. The proper answer to: Where is the best place in town to get a steak dinner? is…You should go to Mel's Diner and get the fried chicken. 2. Big game animals can tell the difference between .015 of an inch in diameter, 15 grains of bullet weight, and 150 fps. 3. There is a difference in the performance of two identical projectiles launched at the same velocity if they came from different cartridges. 4. While a double rifle is the perfect DGR, every 375HH bolt gun needs to be modified to carry at least 5 down. 5. While a floor plate and detachable box magazine both use a mechanical latch, only the floor plate latch is reliable. Disregard the fact that every modern military rifle uses a detachable box magazine. 6. The Remington 700 is unreliable regardless of the fact it is the basis of the USMC M40 sniper rifle for 40+ years with no changes to the receiver or extractor and is the choice of more military and law enforcement sniper units than any other rifle. 7. PF actions are not suitable for a DGR and it is irrelevant that the M1, M14, M16, & AK47 which were designed for hunting men that can shoot back are all PF actions. 8. 95 deg F in Africa is different than 95 deg F in TX or CA and that is why you must worry about ammunition temperature in Africa (even though most safaris take place in winter) but not in TX or in CA. 9. The size of a ding in a gun's finish doesn't matter, what matters is whether it’s a safe ding or not. 10. 1 in a row is a trend, 2 in a row is statistically significant, and 3 in a row is an irrefutable fact. 11. Never buy a WSM or RCM cartridge for a safari rifle or your go to rifle in the USA because if they lose your ammo you can't find replacement ammo but don't worry 280 Rem, 338-06, 35 Whelen, and all Weatherby cartridges abound in Africa and back country stores. 12. A well hit animal can run 75 yds. in the open and suddenly drop with no initial blood trail, but the one I shot from 200 yds. away that ran 10 yds. and disappeared into a thicket and was not found was lost because the bullet penciled thru. I am 100% certain of this even though I have no physical evidence. 13. A 300 Win Mag is a 500 yard elk cartridge but a 308 Win is not a 300 yard elk cartridge even though the same bullet is travelling at the same velocity at those respective distances. | |||
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I've run into the same problem on sporterized Mausers. Even though the holes are straight and inline with the bore, the top of the action may cause the rear mount to lean to one side. Mark Pursell | |||
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Mike, The two piece mount I was trying to use was a QD from Leupold. After thorough examination I discovered the cam-lock on the bottom of the post was waaaaaaaaaaaaaay out of location and no it was not installed backwards. Don't feel like trying another set at this time. One piece mount fixed the problem. We Band of Bubbas N.R.A Life Member TDR Cummins Power All The Way Certified member of the Whompers Club | |||
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For a gun to shoot 48" off at 100 yards (3600") a rifle with 20" of barrel sticking out of the action would have to be bent .2666667" (Basically 1/4" over the length of the barrel) 48/3600 * 20 = 0.26666666666666667 Frank "I don't know what there is about buffalo that frightens me so.....He looks like he hates you personally. He looks like you owe him money." - Robert Ruark, Horn of the Hunter, 1953 NRA Life, SAF Life, CRPA Life, DRSS lite | |||
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Frank, I interpreted his post to being 48 inches off at 50 yards which means assuming a 22 inch bbl that would mean that the rear of the scope would have been around 1/2 inch off center line. So I am still a little confused as to how the upside down cam lock caused a 1/2 of horizontal dispersion. Mike Legistine actu quod scripsi? Never under estimate the internet community's ability to reply to your post with their personal rant about their tangentially related, single occurrence issue. What I have learned on AR, since 2001: 1. The proper answer to: Where is the best place in town to get a steak dinner? is…You should go to Mel's Diner and get the fried chicken. 2. Big game animals can tell the difference between .015 of an inch in diameter, 15 grains of bullet weight, and 150 fps. 3. There is a difference in the performance of two identical projectiles launched at the same velocity if they came from different cartridges. 4. While a double rifle is the perfect DGR, every 375HH bolt gun needs to be modified to carry at least 5 down. 5. While a floor plate and detachable box magazine both use a mechanical latch, only the floor plate latch is reliable. Disregard the fact that every modern military rifle uses a detachable box magazine. 6. The Remington 700 is unreliable regardless of the fact it is the basis of the USMC M40 sniper rifle for 40+ years with no changes to the receiver or extractor and is the choice of more military and law enforcement sniper units than any other rifle. 7. PF actions are not suitable for a DGR and it is irrelevant that the M1, M14, M16, & AK47 which were designed for hunting men that can shoot back are all PF actions. 8. 95 deg F in Africa is different than 95 deg F in TX or CA and that is why you must worry about ammunition temperature in Africa (even though most safaris take place in winter) but not in TX or in CA. 9. The size of a ding in a gun's finish doesn't matter, what matters is whether it’s a safe ding or not. 10. 1 in a row is a trend, 2 in a row is statistically significant, and 3 in a row is an irrefutable fact. 11. Never buy a WSM or RCM cartridge for a safari rifle or your go to rifle in the USA because if they lose your ammo you can't find replacement ammo but don't worry 280 Rem, 338-06, 35 Whelen, and all Weatherby cartridges abound in Africa and back country stores. 12. A well hit animal can run 75 yds. in the open and suddenly drop with no initial blood trail, but the one I shot from 200 yds. away that ran 10 yds. and disappeared into a thicket and was not found was lost because the bullet penciled thru. I am 100% certain of this even though I have no physical evidence. 13. A 300 Win Mag is a 500 yard elk cartridge but a 308 Win is not a 300 yard elk cartridge even though the same bullet is travelling at the same velocity at those respective distances. | |||
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I had the very same problem with the Leupold QD mounts. I tried 3 different sets on a Rem in .416 Rem. ran out of windage on all 3 sets and still was a good distance away from the center. Went to Talley QD and the problem went away. | |||
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Mike, It wasn't upside down, just in the wrong place. Since then I have setup not less than 7 sets of Leupy QD rings on a fixture I built out of Thompson Shafting. With an indicator and an indexing head I have found cam slot on the posts to be as different as .020" in the vertical location and .015" radially in relation to parallel with the ID of the rings. I have sent my results along with my fixture and several sets of rings to Leupy. Hopefully they can find their QC problem. For now, I am done with QD mounts from them. Andy FWIW It was 3ft off not 4. Don't know where 48" came from. AB We Band of Bubbas N.R.A Life Member TDR Cummins Power All The Way Certified member of the Whompers Club | |||
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Andy, Thanks for the info...the 4ft came from your post.
Mike Legistine actu quod scripsi? Never under estimate the internet community's ability to reply to your post with their personal rant about their tangentially related, single occurrence issue. What I have learned on AR, since 2001: 1. The proper answer to: Where is the best place in town to get a steak dinner? is…You should go to Mel's Diner and get the fried chicken. 2. Big game animals can tell the difference between .015 of an inch in diameter, 15 grains of bullet weight, and 150 fps. 3. There is a difference in the performance of two identical projectiles launched at the same velocity if they came from different cartridges. 4. While a double rifle is the perfect DGR, every 375HH bolt gun needs to be modified to carry at least 5 down. 5. While a floor plate and detachable box magazine both use a mechanical latch, only the floor plate latch is reliable. Disregard the fact that every modern military rifle uses a detachable box magazine. 6. The Remington 700 is unreliable regardless of the fact it is the basis of the USMC M40 sniper rifle for 40+ years with no changes to the receiver or extractor and is the choice of more military and law enforcement sniper units than any other rifle. 7. PF actions are not suitable for a DGR and it is irrelevant that the M1, M14, M16, & AK47 which were designed for hunting men that can shoot back are all PF actions. 8. 95 deg F in Africa is different than 95 deg F in TX or CA and that is why you must worry about ammunition temperature in Africa (even though most safaris take place in winter) but not in TX or in CA. 9. The size of a ding in a gun's finish doesn't matter, what matters is whether it’s a safe ding or not. 10. 1 in a row is a trend, 2 in a row is statistically significant, and 3 in a row is an irrefutable fact. 11. Never buy a WSM or RCM cartridge for a safari rifle or your go to rifle in the USA because if they lose your ammo you can't find replacement ammo but don't worry 280 Rem, 338-06, 35 Whelen, and all Weatherby cartridges abound in Africa and back country stores. 12. A well hit animal can run 75 yds. in the open and suddenly drop with no initial blood trail, but the one I shot from 200 yds. away that ran 10 yds. and disappeared into a thicket and was not found was lost because the bullet penciled thru. I am 100% certain of this even though I have no physical evidence. 13. A 300 Win Mag is a 500 yard elk cartridge but a 308 Win is not a 300 yard elk cartridge even though the same bullet is travelling at the same velocity at those respective distances. | |||
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My bad. Should have been 3ft, those numbers are really close on the keyboard, I must have fatfingered the keys. My original post says 3ft. Not to worry, problem solved. I used the exact same scope too! Andy We Band of Bubbas N.R.A Life Member TDR Cummins Power All The Way Certified member of the Whompers Club | |||
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Just to satisfy my own curiosity. If the problem is a ring being offset slightly, then wouldn't the sight radius used in the calculation be the distance between the rings? If the error is 48", distance to target is 1800" (50 yards) and the distance between rings is 4", that would be (48/1800)*4= .107 . Mark Pursell | |||
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