How to true the BC

[nksmfamjp]

Ok gents, my bad on the math. I only have 1 mil scope, an old S&B. Pretty sure adjustments on it were set at 100 meters. I apologize for my inability to sipher.

Yea, S&B and some of the euro folks try to be confusing by calling their mil scopes 1 cm adjustment (at 100m)….which is still 1/1000 ratio.

 

[bsnyder]

Great thread! Thanks op!

 

[Ucsdryder]

Your scope wouldn't have been set up a different way you just thought in a different measurement. If you are thinking in meters then you could have every .1 mil is 1 cm at 100 meters. It is the same angular measurement as every click is .36 inches at 100 yards. Just a different way to think about it. The only time that I ever think of it that way is if I am zeroing and do not have a good reticle. Otherwise, I just measure with the reticle and come over/up what the reticle tells me. This is where I got very confused and I feel like a lot of guys do because they are trying to convert it to inches. I still have no idea how many cm go into an inch but it is really irrelevant when shooting because you simply want to measure your poi in mils and make the correction that way.

I am sure this sounds confusing and I will tell you that I was so confused when going from MOA to Mils! I just had to train myself to think in mils and not try to convert it to a stagnant unit of measurement that changes as distance changes. Use what your ballistic calculator spits out for elevation and for wind, use the wind formula that I have mentioned in previous posts to get the angular measurement in mils. Otherwise, stuff gets really confusing!

I reached out to vortex regarding the tracking. He said he wasn't sure what the margin of error they allowed for their LHT 3-15 but said often the rings and how they were mounted could impact the tracking. He strongly suggested lapping rings and using no loctite. I explained the RTZ wasn't my issue, it was the accuracy of 1 mil, and he confirmed that could be due to torque settings and rings. Is this your experience?

 

[XLR Industries]

I reached out to vortex regarding the tracking. He said he wasn't sure what the margin of error they allowed for their LHT 3-15 but said often the rings and how they were mounted could impact the tracking. He strongly suggested lapping rings and using no loctite. I explained the RTZ wasn't my issue, it was the accuracy of 1 mil, and he confirmed that could be due to torque settings and rings. Is this your experience?

I would say if the rifle was not grouping well then you could look at the rings and torque setting. As long as you are running the Recommended torque from Vortex then that shouldn't have anything to do with the tracking. The only way I could really see them being an issue is if you had them over-torqued or if they were super out of alignment and causing a pinch point in the scope. Typically the only way that this would happen is if you were running a base that isn't straight on a 700 or other factory action. I ran into this in the past on one of my 700s so I bed them all now and just run a spur mount. That way any misalignment is going to be taken up by that Spuhr and not transferred up into the scope. It is really just a bandaid on the issue but I know that if I put that scope on any rifle it will always be stress-free! If you are running a custom action then I think the Spuhr is probably overboard and you should be able to just run some Hawkins and be just fine (and save you a little weight).

 

[280AI rl]

I would repeat the test after measuring out the distance again. Rangefinders can be plus or minus a few yards just based on reflectivity/color of your target. In my experience, Euro RFs show this amount of error regularly. Based on the calculations provided by previous poster you are within the potential for error. You need to have accuracy in your measurement from target to reticle.