Help with 338 Lap mag in a AWM (UK)

[nthor]

Hi I have a AI AWM 338 Lap Mag and have found a load that performs well so far. I have just come back from a local range yesterday I will enter all data below and have tried to work back my scope data to make a full chart but its not liking what I achieved yesterday and I cant get the suggest scope data to line up so any help or suggestions welcome.

Range was Sennybridge in Wales (uk) 1000 ft above sea level, temp was 41f wind was 11oc 6 mph.

Load was 250g Lapua Scenar pushing 2988 fps

Rifle zero data was 100 yards, temp 55f and this was done at sea level.

Data on the day was:

1000y 7.9 Mil elevation
1200y 9.6 Mil
1548y 13.3 Mil

I was knocking down the 1000y and 1200y Fig 11 target (UK Army training target) with ease, the 1548y 2-3 from 5 shots where hits.

The issue is I can't get the NF software to give me a scope setting data that makes any sense to include the above ark of fire.

Any ideas or suggestions, thanks in advance

 

[Sendero_Man]

Re: Help with 338 Lap mag in a AWM (UK)

are you using the trajectory validation feature ?

 

[CoryT]

Re: Help with 338 Lap mag in a AWM (UK)

First, is the scope calibrated? Second, how accurate are the ranges? Third, did you get to see where the hits were on the targets? Last, actual station pressure would be more helpful than altitude. I'm not sure there is enough good info here to provide much of an answer.

I've used the 250 Scenar extensively. I show 6.8, 9.4, 15.3 for 1000, 1200 and 1548 yards under standard conditions for 1000' MSL. I doubt the actual conditions were different enough to account for the differance. The only value that looks reasonable to me is your 1200y setting, which is plenty close for scope height or calibration to be the difference.

You need a scope calibration, a weather meter and the ability to spot hits, as well as verified ranges. I've seen plenty of 1000 yard targets at 100 yards +/- actual, or range signs in yards for targets laid out in meters.

 

[nthor]

Re: Help with 338 Lap mag in a AWM (UK)

I have tried to but it crashes every time

 

[nthor]

Re: Help with 338 Lap mag in a AWM (UK)

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CoryT</div><div class="ubbcode-body">First, is the scope calibrated? Second, how accurate are the ranges? Third, did you get to see where the hits were on the targets? Last, actual station pressure would be more helpful than altitude. I'm not sure there is enough good info here to provide much of an answer.

I've used the 250 Scenar extensively. I show 6.8, 9.4, 15.3 for 1000, 1200 and 1548 yards under standard conditions for 1000' MSL. I doubt the actual conditions were different enough to account for the differance. The only value that looks reasonable to me is your 1200y setting, which is plenty close for scope height or calibration to be the difference.

You need a scope calibration, a weather meter and the ability to spot hits, as well as verified ranges. I've seen plenty of 1000 yard targets at 100 yards +/- actual, or range signs in yards for targets laid out in meters. </div></div>

Hi, Ranges are good (done with Zeiss RF) but a hit is a hit so it could be any place in the 44x17 inch target, The scope is a S&B PM11 5-25x56 so good glass. I did not get the pressure on the day but just checking on the met office for yesterday showed 1033 for where I was, but the ark of fire and the Mill settings i used just don't add up. I guess I will have to try again when I get onto a gallery range where I have some butt markers. Scope is 2 1/4 inch to bore "centre to centre"

 

[CoryT]

Re: Help with 338 Lap mag in a AWM (UK)

With a 44" vertical target area, that's 1.2 mil of error you can't see. Even S&B's need calibration, I've got a couple that run .104 per click and that does add up. 1033 puts you at about -200' DA, just FYI. You'll need steel or butts where you can pull targets.

 

[nthor]

Re: Help with 338 Lap mag in a AWM (UK)

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CoryT</div><div class="ubbcode-body">With a 44" vertical target area, that's 1.2 mil of error you can't see. Even S&B's need calibration, I've got a couple that run .104 per click and that does add up. 1033 puts you at about -200' DA, just FYI. You'll need steel or butts where you can pull targets.</div></div>

yep will have to wait, thanks

 

[Emouse]

Re: Help with 338 Lap mag in a AWM (UK)

Nigel,...If your using the AI 45moa one pieve mount then the bore to scope centreline is 3"!

Or are you usingthe 28 MOA rail with the cut out??

I had a similar problem yesterday with software ( Bulletflight) giving huge over correction on elevation at 1k ( .308) compared to what we actually saw arriving on target. The fast wind shift and fact that determining real wind speed/direction over several down range features stopped us from getting a tue "wind picture".

Using an MSR ret in the SuB does help fast accurate corrections in constant conditions.