Climbing trajectory

[TXFRNTLDER]

So I have a load of 95 grns. and the 240 grn XTP seems to be working pretty good at 50 yards. When I go out to 100 it climbs, I was perplexed then remembered seeing ballistics charts where at closer distances the trajectory is listed as a negative ie.. -2.1 inches I pressume meaning the bullet actually climbs which is what I think my 240 XTP's are doing. I'd like to be flat out to 100, what do I do? Go up to a 300? I really don't want to go down in powder, I wanna keep the velocity up there.

[cayugad]

Sight in dead on at 100 yards. Then go back and check where the rifle hits at 50 yards, 25 yards, etc. I think you would be happy with that.

[dmurphy317]

"I'd like to be flat out to 100"

No bullet shoots dead flat, there is always some arc. Faster velocities will flatten out that arc but it will never be "flat", unless you can push it to light speed.

Trajectory is what it's called and it's something that needs to be understood, especially by those of us that shoot frontstuffers at the velocities they work best at. What you may want to do is examine the point blank range (PBR) sight innumbers for the loads you are working with. I find this info helpful in understanding the limits of the load and then combine my personal limits with the loads limits to determine what is reasonable and feasable to expect of the load.

For instance, take your load of 95gr of powder and a 240gr bullet. Using 1750 as a velocity and .2 bc (these are just guesses for illustrative purposes) if you use a 2" PBR you sight in at 100 yards and your up 1" at 60 and down 1" at 115. For a 4" PBR you sight inat 122 and your up 2" at 75 and down 2" at 142. For a 6" PBR you sight in at 140 and your up 3" at 80 and down 3" at 164. Faster velocities will extend the spread of the numbers but will not make it a laser beam.

A little time studying trajectory charts helps a lot in visualizing what the bullet is doing (path wise) when it leaves the muzzle. I find this helps me in estimating hold over on longer shots as well as having the confidence to point and shoot when the target is within the PBR I'm setup for.

Good luck with your load.

[Pglasgow]

ORIGINAL: TXFRNTLDER

So I have a load of 95 grns. and the 240 grn XTP seems to be working pretty good at 50 yards. When I go out to 100 it climbs, I was perplexed then remembered seeing ballistics charts where at closer distances the trajectory is listed as a negative ie.. -2.1 inches I pressume meaning the bullet actually climbs which is what I think my 240 XTP's are doing. I'd like to be flat out to 100, what do I do? Go up to a 300? I really don't want to go down in powder, I wanna keep the velocity up there.

Do you have see through mounts on your scope? If so, your sight height is on the order of 2.25 inches. If so you'll be 2 3/4" high at 100 if you sight 2" high at 50. Take a ruler and measure the distance from bore center to the center of scope and use that number in the sight height field when running the ballistics program. Maybe that'll help?

[TXFRNTLDER]

Can't believe you guys didn't correct me on my mistake on the negative vs. positive on the shorter range trajectory.

[TXFRNTLDER]

ORIGINAL: dmurphy317

"I'd like to be flat out to 100"

No bullet shoots dead flat, there is always some arc. Faster velocities will flatten out that arc but it will never be "flat", unless you can push it to light speed.

Yeah I do realize that, I'm just refering to the term flat shooting that is used for the higher velocitycalibers that do not have so much drop at short to moderate ranges.

[Underclocked]

Bullets don't climb.


Your trajectory curve is going to remain constant so long as your load remains constant. All you can do is vary the launch angle (line of bore).

[TXFRNTLDER]

ORIGINAL: Underclocked

Bullets don't climb.


Your trajectory curve is going to remain constant so long as your load remains constant. All you can do is vary the launch angle (line of bore).

Then this means you have TWO zero's on your scope? One close where the bullet shoots out relatively "flat" then again down range when the bullet comes back down?

The reason I ponder this is because I am dead on at 50 yards then high at 100. Maybey I am back to dead on on out at 150 175?

This has really peaked my interest and actually is inspiring me to spend more time on the range to tweak this in just right. All part of the fun.

[MO Archer]

ORIGINAL: TXFRNTLDER

Then this means you have TWO zero's on your scope? One close where the bullet shoots out relatively "flat" then again down range when the bullet comes back down?

The reason I ponder this is because I am dead on at 50 yards then high at 100. Maybey I am back to dead on on out at 150 175?

This has really peaked my interest and actually is inspiring me to spend more time on the range to tweak this in just right. All part of the fun.

No expert here....but if you sight it dead on at 100yds like stated earlier your 'two' zeros should theoretically be at your muzzle and at 100yds. Someone set me straight if this is way off.

[lemoyne]

MO Archer, If you are using a scope the bullet normally starts out at -1.5 inches crosses the line of sight at about 30yds depending on velocity and distance sighted in for"0" it will make a lot of differance if you are using irons, heavy loads and light bullets also make a differance. Sabotloader and several people have put charts up on here in the past some of them were recent youall might find it quite interesting to go back and study the differances load and bullet weight make. For example the comparision of the 50/40 200gr the 250 gr and the 300gr was suprising to me. Lee