Big discrepancy between chrono MV and real world shooting. Why?

[bmart2622]

My goodness, my point got taken out of context. I’m done with this thread.

Good idea!!

 

[Hondo64d]

I don't want to derail, but I have a related question.

How many of you don't use a chrono at all?

I don't own one. I zero at 100 yards. Take the velocity of the box, minus 30 fps per inch if the barrel is less than 24 inches. Put that into the calculator (Shooter) to get "try" dope. Shoot at 300 and 500 yards. (my range only goes to 500). Tell the calculator what my actual drops are and let it figure out what it thinks my MV is. Anyone see an issue with this process?

I have a chrono but don’t use it often. Typically, I make an educated guess at MV, get a good 100 yard zero, then go to 800 or 900. I see where I hit there, put that into Ballistic AE and let it calculate the MV. I don’t recall ever having to make any change after doing this. Inputting accurate values for all the other factors is important. Sight height, zero offset, environmentals, etc.

John

 

[Hoosker Doo]

Well, during recovery I was able get another batch of reloads going, and today I managed to get out for an hour or so to tune up my zero.
After wasting several rounds learning that you shouldn't attach a bipod to a Ruger No. 1, I shot 2 more groups with some adjustment in between to get dead on at 100 yards. I squeezed off another verification shot or two, just to make me feel good as I ran out of time and my barrel was getting pretty warm. Now I can say I'm "dead nuts" at 100.
Hopefully tomorrow, I can shoot at some distance. My plan is to set up a tall target at 400 yards or so and shoot without dialing and use my actual drop below point of aim to see where that puts me for velocity.

 

[Hoosker Doo]

I figured I should offer a follow up post after receiving some great advice on this thread.
It's amazing to me the precision required to be precise at long range. I'm gradually transitioning from just a hunter to a shooter as well. The hunter in me said "if it's within an 1" of the point of aim, then it's sighted in". But 1/2" high at 100 yards was the cause of most of my problems of being 2 MOA high at 420 yards.
After shooting multiple times, I did decide to adjust my muzzle velocity to closer to 3100 fps from the original 3033 fps. But by just getting my zero "dead nuts", with that adjustment my dialing come up is only 1/4 MOA off of what it was when I was shooting 2 MOA high, but now I am hitting dead on for elevation.
Thanks sharing your wisdom. My goal is to shoot proficiently for hunting for hunting within 600 yards. After dabbling in long range as much as I have with zeroing, adjusting, verifying and practicing, it's amazing to me the number of people who act like a 700-900 yard shot is nothing who I know aren't slinging lead downrange at those ranges to practice or verify until there's a critter in their scope.

 

[NSI]

I figured I should offer a follow up post after receiving some great advice on this thread.
It's amazing to me the precision required to be precise at long range. I'm gradually transitioning from just a hunter to a shooter as well. The hunter in me said "if it's within an 1" of the point of aim, then it's sighted in". But 1/2" high at 100 yards was the cause of most of my problems of being 2 MOA high at 420 yards.
After shooting multiple times, I did decide to adjust my muzzle velocity to closer to 3100 fps from the original 3033 fps. But by just getting my zero "dead nuts", with that adjustment my dialing come up is only 1/4 MOA off of what it was when I was shooting 2 MOA high, but now I am hitting dead on for elevation.
Thanks sharing your wisdom. My goal is to shoot proficiently for hunting for hunting within 600 yards. After dabbling in long range as much as I have with zeroing, adjusting, verifying and practicing, it's amazing to me the number of people who act like a 700-900 yard shot is nothing who I know aren't slinging lead downrange at those ranges to practice or verify until there's a critter in their scope.

It sounds like you're well on your way to getting confident at longer ranges!
If you ever want to get together and shoot, I'm about a half hour north of you.

-J