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Looking for some advice please. I have a Winchester M70 in 375 H&H. I originally bought a Luepold VX-III 2.5-8 for it, but found that the scope did not have enough vertical adjustment to get it on target. The best I could do was get it to 6 inches low at 100 yards. The scope was mounted with warne bases and quick release rings. I switched scopes to a VX-III in 1.5-5, and everything was fine. I assumed it was the scope, so I sent it to Luepold. They checked it out and said that everything was fine. Any ideas? I'd like to have a little more scope on this rifle than the 1.5-5. Pete | ||
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Your 1.5-5X scope has only 10 additional inches of adjustment over the 2.5-8X (75" vs 65"), so your new one is near maxed out as well. It doesn't sound right to me. If it were a windage issue I'd suspect the mount holes were drilled at an angle; otherwise, I'd look at the bases and rings to see how they line up w/ the bore axis. Sounds to me like your setup has the scope mounted on too steep an incline if you need that many inches of adjustment to overcome. GVA | |||
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When you put your scope back on, optically center the adjustment and then bore sight it. It should show if you need to shim anything. This is pretty simple to do, adjust the back base in the direction up or down you want to move the bullet impact. Jim Kobe 10841 Oxborough Ave So Bloomington MN 55437 952.884.6031 Professional member American Custom Gunmakers Guild | |||
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Talentrec I had the same problem when mounting a couple of scopes for some family members. If you are committed to the rings and bases you already have then as has been pointed out shims are one way to go. In addition, you can do as I did one one of the rifles and carefully remove metal from the underside of the base of the end that is too high. I used a very fine rounded stone. It took quite a bit of fit and try but it works. Or, another thing you can do that I have done on my rifles is go to the Burris Signature system. That system has rings that are oversize and take plastic inserts that have different thicknesses. So, for example, by the way you install them, you could put plus .030 in the front and a turn that around to have a minus .030 in the rear. They work great, and another advantage of them seems to be that they don't mar the scope as much. I now have them on all of my rifles. | |||
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Some fundimental problems here are that 1. Many receivers are quite far off and in some cases the scope mount bases must be machined to fit the situation. Other methods are shimming, adjustable mounts and now the Signauure system of eccentric inserts. Since this is a 375 HH with potential DGR use along with substantial recoil I suggest fitting bases to the receiver. This will take time and cost money if a smith does it but then it will be optimum for that mount. 2. Another problem with scope adjustments is that if say the windage is way off in scope to bore alignment then it will jam the system to one side and limit the elevation adjustment range too! If the rifle has and might want to be used with iron sights also then a mount system should be fitted that will allow the irons to be seen with the scope off and to also field change the scope to a back up. Then have the mount fitted to center the reticule. Join the NRA | |||
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Thanks for the info guys! If I have to shim one of the bases, will that create excess torque on the scope? Pete | |||
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Depends on how much you need to shim it. If you place too much of a load on the tube your optics will suffer. Same as if you were to crowd the bell of the tube, or, even the turrets with your rings. Further, if your scope adjustments are near the end of their travel, that can distort the optics and change your point of impact. An out of whack crown can also affect your point of impact. If the bullet is releasing at an odd angle, it can send your bullets low. I don't know how well your rifle groups now, but if you were to add pressure to the barrel, say at the tip of the forend, that would raise your point of impact. | |||
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It may not because you may be correcting the misalignment already there. I'd second the Burris Zee rings, a plus .020" insert in the front will probably get you close to zero and the plastic inserts will seat themselves in the rings and not stress your scope tube. I have them on a light recoiling 6.5x284. 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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The rifle is fully bedded and I don't think there's anything wrong with the crown (it shoots well). So, if the scope is turned all of the way to the "up" position and still shoots low, does that mean that the cross hairs are all the way to the bottom of the scope? So, to correct this problem would I need to lower the front and raise the back, or do I have it backwards? Thanks, Pete | |||
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You move the back of the scope in the direction you want your bullets to move. Raise the back of the scope and the POI will follow. Move it to the right and your POI will move right... | |||
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Model 70's are notorious for having receiver variations and misdrilled holes for scope mounts. The problem is common enough that Talley makes different thickness bases for Model 70's to correct the problem. Contact Gary Turner at Talley manufacturing and he can hook you up with bases to compensate. Of course you will also have to use thier excellent rings with thier bases but that's a good thing..................DJ ....Remember that this is all supposed to be for fun!.................. | |||
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You're also far and away better off to either epoxy or plastic steel the bases onto the receiver, rather than using a shim method. You can do this by applying a release agent on the receiver and using a generous amount of epoxy, steel bed, acraglass, etc. on the bases....This system won't be getting shot loose from heavy recoil and will ensure from that day forward, you won't have to worry about the shim working its way loose. Even on a set of bases that have been machined specifically for the receiver, it won't match in all areas of the base, so the epoxy method will work there also. What you do gain by having the bases machined for the receiver is that the cosmetic appeal increases and you will see less gap between the bases and the receiver. Glass bedding or epoxying the bases is no different than glass bedding your action. They both should be done and the process can't be replicated with shims or machining, despite claims to the contrary. Not to say that you can't get it close with the other two options, but for it to be perfect, or at least close as possible to perfect, it's the only way to fly. Not to mention, it's pretty damn fast and easy to do yourself.  Williams Machine Works | |||
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This would make it a little nicer because you can bed the entire length of the base the desired angle to prevent any chance of distorting the scope. They sell commercially produced 20-25 MOA bases to give the shooter more elevation, but they typically sell for about $175.00 just for the base. You would essentially be getting the same results but at a much reduced cost. Expanding a little on what Matt has said, unless you are fairly patient and have the means to measure and block up two bases, keeping them perfectly aligned while the epoxy cures, I might recommend the use of a one piece base for this. This will take all the guess work out of the set up so all you would need to do is apply release agent to the receiver, screws and holes, load the base with epoxy, being careful of any over flow, elevate the back of the base to provide perhaps .030 - .040 elevation, wipe up the excess, and let it cure. | |||
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I use the Farrell 20 MOA base on my MRC short action. For the Winchester long action they run about $65 Here's a link to Graf's page on them: https://www.grafs.com/fc/product/3908 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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Thanks for the link. | |||
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Thanks for all the input guys. I put two .012 shims under the rear base and got the crosshairs pretty much on center. I'm going to try and shoot it this weekend; if it works I'll try something more permanent. Pete | |||
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The rear mounts/rings need to be taller than the front mount/ring. Make sure you don't have two fronts or two rears. Jaywalker | |||
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