hellier0437 Posted May 22, 2007 Report Share Posted May 22, 2007 i have just bought a ruger 10/22 and want to zero it. I have a choice of sloping and flat land but am not sure which to use. preferably i would like to shoot downhill for safety but will ths alter my POI on a target? if so, by how much? Thanks for any help tom Quote Link to comment Share on other sites More sharing options...
lurcherboy Posted May 22, 2007 Report Share Posted May 22, 2007 Do both ? LB Quote Link to comment Share on other sites More sharing options...
hellier0437 Posted May 22, 2007 Author Report Share Posted May 22, 2007 i was worried about the flat bits because of the difficulty in finding a suitable backstop Quote Link to comment Share on other sites More sharing options...
lurcherboy Posted May 22, 2007 Report Share Posted May 22, 2007 i was worried about the flat bits because of the difficulty in finding a suitable backstop Then in no way should you use the 'flat' option to zero LB Quote Link to comment Share on other sites More sharing options...
naddan28 Posted May 22, 2007 Report Share Posted May 22, 2007 i was worried about the flat bits because of the difficulty in finding a suitable backstop Then in no way should you use the 'flat' option to zero :( LB :yp: as for how much the POI will shift well...how steep is the hill? Quote Link to comment Share on other sites More sharing options...
henry d Posted May 22, 2007 Report Share Posted May 22, 2007 Negligible for .22lr ranges I would have thought unless you are shooting over 30" below/above the horizon. Quote Link to comment Share on other sites More sharing options...
taff915 Posted May 22, 2007 Report Share Posted May 22, 2007 the only input i can give is i fire army issue sa80 we zero on flat ranges but use them on all terrain and still hit. dont know if thats any help really ?? i would say its down to range rather than incline/decline Quote Link to comment Share on other sites More sharing options...
steve b Posted May 22, 2007 Report Share Posted May 22, 2007 make some decent sand bags and use them as back stop, cheap and effective hope this helps steve b Quote Link to comment Share on other sites More sharing options...
codling99 Posted May 22, 2007 Report Share Posted May 22, 2007 or pick a few up off side of road... :( Quote Link to comment Share on other sites More sharing options...
CharlieT Posted May 22, 2007 Report Share Posted May 22, 2007 Yes it will make a difference. If you are far cleverer than I........... read this http://en.wikipedia.org/wiki/Rifleman_rule Charlie Quote Link to comment Share on other sites More sharing options...
pin Posted May 23, 2007 Report Share Posted May 23, 2007 Wow, very interesting. The simple answer is shooting up or down a hill your POI will be low compared to your POA. Quote Link to comment Share on other sites More sharing options...
Dunkield Posted May 23, 2007 Report Share Posted May 23, 2007 Intresting but wrong, shooting uphill or downhill the POI is always higher, due to the fact there is less gravitational force applied In fact there was full explanation of it the free hunters guide that was given away with one of the shooting mags, I know 'cos some bloke at work was boring me to death with it . . Quote Link to comment Share on other sites More sharing options...
Dunkield Posted May 23, 2007 Report Share Posted May 23, 2007 From the snipercountry site.. "Shooting Uphill/Downhill Bullet drop does not change very much when shooting uphill/downhill. But the rifle will appear to shoot high. In fact it shoots high by almost the same amount whether you are shooting up or down. Therefore you must adjust your hold or change your scope when taking shots at high angle, especially as range increases. If you know what the drop (d) is for your bullet at any given range, you can use the following table to calculate the amount your bullet will shoot high, in inches. Think about a 600 yd shot downhill at 40 degrees -- Instead of a 50" correction we are talking about a 40" correction. Check your tables or ballistics program for your rifle. If you would like to know what it is right now, then try JBM's online ballistics calculator! Just use your "back" button on your web browser to return." Quote Link to comment Share on other sites More sharing options...
pin Posted May 23, 2007 Report Share Posted May 23, 2007 Intresting but wrong, shooting uphill or downhill the POI is always higher, due to the fact there is less gravitational force applied :( I did mean high It's early. Slight correction in what you say as well stuart, exactly the same gravitational force has been applied. Gravitational force is related only to the mass of an object and is a physical constant. The easiest way to imagine it :- Bullet has a curved path. It rises above POI and falls back down to the POI, on level ground. On a hill, with the same zero, the bullet would rise above the expected POI and strike the target before it had a chance to fall to the expected zero'd POI - which means earlier in its travel, which means higher up on the curve. Quote Link to comment Share on other sites More sharing options...
Dunkield Posted May 23, 2007 Report Share Posted May 23, 2007 Slight correction in what you say as well stuart, exactly the same gravitational force has been applied. Gravitational force is related only to the mass of an object and is a physical constant. Funny thing is last time I used those exact same words someone corrected me What I mean to say is gravity is applied for less time/distance/whatever :( In practical terms, I never give this stuff a seconds thought as it always results in a miss. I have shot 2 hinds stood next to each in Scotland shooting down at 45 degrees, the shots were about 120 yards, it was only after when my mate said 'did you aim low' that I gave it a seconds thought. And no I didn't, they both went down and didn't get up again. Quote Link to comment Share on other sites More sharing options...
JohnGalway Posted May 23, 2007 Report Share Posted May 23, 2007 It'll affect longer range shots more. Or shooting at very small targets. At the ranges most of us shoot here, yeah it doesn't matter a whole lot but isn't it the right idea to have your rifle set up in the best way it can be. Quote Link to comment Share on other sites More sharing options...
pin Posted May 23, 2007 Report Share Posted May 23, 2007 I bet for most practical purposes this can be ignored at "normal" ranges. Quote Link to comment Share on other sites More sharing options...
JohnGalway Posted May 23, 2007 Report Share Posted May 23, 2007 I was about to post something else but my head hurts from trying to work it out so I can't be bothered as I'd not be sure of the facts :( Quote Link to comment Share on other sites More sharing options...
Dunkield Posted May 23, 2007 Report Share Posted May 23, 2007 It makes no difference to us mortals (except those of us regulary take foxes out to 400 yards with their hmr's of course) But I still maintain is a useful excuse to keep in your back pocket for an inexplicable miss :( It certainly has a lot more cred then "that's odd, my scope my have taken a knock" Quote Link to comment Share on other sites More sharing options...
JohnGalway Posted May 23, 2007 Report Share Posted May 23, 2007 I was watching a DVD yesterday that had a bit of longer range shooting on it. Guy was shooting out past 400 yards, using a sling and only resting on what he found out there like rock or a fallen tree. Took a few shots down and uphill in a LOT of wind. Hit everytime Quote Link to comment Share on other sites More sharing options...
Dunkield Posted May 23, 2007 Report Share Posted May 23, 2007 I am glad you enjoyed my film John :( There is long range shooting site on the web somewhere they shoot out to 800 yards, free standing Quote Link to comment Share on other sites More sharing options...
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