Hello I'm going on a hunt this year in an area around 7,500 feet in elevation. The problem is that there is no way for me to sight in my rifle up there and I live around 400 feet. Any suggestions on how I might solve this problem. I want my rifle sighted in at 100yds. I'm shooting an old ruger m77 .270 150 grain. Thanks
Sight it in where you live and go hunting. There won't be enough difference that you'll be able to tell under normal hunting conditions. I have no idea what your maximum shot distance will be, but most that hunt out west will zero their rifle at 200 yards, which means 2-3 inches high at 100 yards. That way you can hold dead on the vitals of an animal from close up to 300 yards or so and not worry about missing high or low. Just remember to hold a little lower on the vitals on a steep shot uphill or downhill if the shot is of any real distance.
Ok. Also what would a 30-40 degree temperature change do to the bullets travel?
Same answer...sight it in where you live and go hunting. You won't see any difference at most of the ranges you will be shooting. Don't overthink it, if you were shooting at extreme ranges (700+ yards), then you need to know.
Cowboy Action Shooter; Endowment Life Member-NRA
The Original Rocket Scientist-Retired
"My Father always considered a walk in the mountains as the equivalent of church going."
Yep! You're putting way too much thought into things that might cause a problem, but really won't! However, I guess it's good to ask questions if you have anything you aren't sure of because you don't want to be worrying about it when it's time to shoot that trophy. Again, temperature won't have much of anything to do with trajectory in a hunting situation. However, if you reload ammo, there are pressure variations that can get you into trouble with accuracy, as well as safety issues, if you try to get close to max at lower temperatures and then go shoot that load at high temperatures. Normally there will be a pressure spike at higher temperatures and it could cause a real problem if it's way over the max suggested for the load. When you use factory ammo all of that is taken into consideration by the manufacturers and the powder is cut down enough so there is no problem when shooting in any rifle out there whether it's at 100 or 20 degrees.
Last edited by Topgun 30-06; 08-30-2014 at 07:38 PM.
There is a really good article in the current EHJ (#144) by Dan Turvey that includes a sidebar dealing specifically with "Shooting at Elevation." It confirms what others have said above and should be helpful in setting your mind at ease.
If you are hunting the west without a turret on your scope, I would suggest sighting your rifle dead on at 200 yards for the reasons that topgun stated. And I wouldn't worry about elevation or temp unless shooting long range.
I asked this same question to a gal who has had the opportunity to shoot with some of the best shooters our country has to offer...her answer was this.."for you it ain't going to matter." LOL enjoy your hunt.
First I agree with all the above, sight in and enjoy your hunt. If the differences in bullets and loads interst you, try picking up a copy of the Sitelite Ballistic Sight-In Program on-line. For us non-competition hunters it'll open your eyes to the difference things like Ballistic Coefficient , bullet shape and scope height. I won't claim it to be the end all for supreme accuracy, but I shoot fo 300WSM with 150 grain PSP Remington bullets and the program has proven to be more accurate than I tend to be. Just be sure to chose the Plot Full Zero Range option.
I agree with most of the above responses and say that it won't matter. However I do feel you deserve a response that may help you learn a little. Temperature has an impact on bullet trajectory just like elevation does. If you sight in on a warm day at 400 feet in elevation, your gun will shoot very close to the same as it will on a cold day at high elevation. If you have the time, log on to Hornady's ballistics calculator and "play" with the numbers to see how different things affect trajectory. Other factors like humidity will have a very small impact as well. I would also recommend learning about maximum point blank range. This concept has you sight your rifle in at a distance that maximizes the range at which you can hold exactly on an animal and still hit the vitals. For instance, some rifles may be zeroed at 250 yards to allow the hunter to hold dead on for any range from zero to 300 yards. Sighting in in this way gives you as the hunter a real advantage when hunting out west. As others have mentioned, read about the effect that angle has on point of impact as well. A steep angle up or down will make your bullet impact higher than it would on a flat ground shot of the same distance. Feel free to send me a PM if you need assistance- would love to help.