Mrad / CM click scope adjustment on S&B PMII FFP

[Jim78]

This may sound like a daft question but I would like to know if there is a simple math sum i could apply for adjustment on the scope when ranging using my Lieca LRF . Example If i am out lamping say and i have Mr Fox in the LRF at 328m would i do the sum .1x distance / 10 = 3.28 adjustment rounded up to 3.3 or am i doing something wrong here ??. My rifle zero is 100m as like to keep things simple .

I am in the process of changing out the Ret as i know it doesn't help me very much having the Imperial Bryant ret with Metric adjustment so i thought i could dial the correction whilst using it in conjunction with the rangefinder .

 

Hope this makes sense to you people who are reading this and i need to get my head around this one . By the way going to change to P4L fine ret,

 

Glad for the advice as i am by no means a long range shooter , all i want to do is to be a bit better at it.

 

Jim

[Shuggy]

No that's not how it works at all. A milliradian is an angle, with 6400 in a full circle (mathmatically it's actually 6283 and a bit, but it was simplified by NATO). You need to adjust the scope so that the angle set on the scope intersects the line of sight with the ballistic trajectory of your ammunition at a particular range. This will change considerably depending on the calibre and load. A ballistic program will find out your 'come ups' from the specific bullet, its velocity and the atmospheric conditions.

[Jim78]

I do chrony my rounds but not at the moment Shuggy as i have lent it out and I have never been the sharpest when it came to maths . I have been doing a few tests on various ballistic calcs using the same info (crap in) but been getting different results out hence that's why i asked the question if it could be done . I have Sierra 6 on PC , have Strelok , and Shooter App on my phone and have been using the Hornady calc as i always use Hornady bullets for reloading but like i said i'm getting mixed results. Maybe it's time to get the chrony back to get the average speed of the rounds properly first then start again. I must admit i feel a bit of a *ick for asking the question now . I think firing rounds at different ranges is going to be the best practice tbh with you.

[jon]

http://www.outdoorhub.com/how-to/2011/07/14/how-to-use-milliradian-adjustable-scopes/

This seems pretty readable...read it when I was loaned a scope marked "0.1 mr" instead of 1cm @100m, but then Im easily confused!

From memory the 4pl reticle is one of those included in the Strelok free ballistic app

[Shuggy]

Jon's article is a very good summary. The beauty of an FFP mil/mil scope is that no maths is required. 'What you see is what you dial' when adjusting for errors.

 

Your ballistic apps should all agree, so I think you're right; make some careful velocity measurements and try again. The one thing that wil change from day to day is the atmospheric conditions. The better ones like Ballistic AE will download them wirelessly from the nearest weather station. Or you can input then directly from a Kestrel etc.

 

Years ago I had a mentor who was fond of saying 'there are no stupid questions'. One of the things that I like about UKV is that most people are very patient and happy to share their knowledge. I'm sure that I've asked a few daft ones!

[srvet]

If you think of you rifle bullet trajectory as if throwing a stone. Your elevation knob sets the upward angle that the barrel is at in order to lob the bullet to hopefully land on the target. Therefore greater elevation elevates the barrel. If you are dialling in all the time then metric turrets and imperial reticle should make little difference but your ballistic calculator should give you a guide of elevation and windage needed. I find strelok better than shooter to be honest but all of these programmes work on a crap in crap out basis. What I have found useful is to validate and adjust the trajectory with actual drop data. Bear in mind that bullet manafacturers often exaggerate the BC and it is easy to overestimate the velocity you think you are getting. Don't sweat if after correction to actual drop data the program gives you a lower velocity than expected so long as the predicted trajectory matches the actual trajectory of your bullet