sighting in

bought a new rifle a few months back , and just getting around to breaking it in . it has a 39''douglas bbl. a late ketland lock, and has very quick ignition . forget to mention is 45 cal.
using 50gr. of 3f goex it is shooting 1 hole groups at 50yds. my question is should i be seeing a 2 to 21/2'' drop difference at 50 yds.. 50 yds. being 2.5 lower than 25yds. just seems like a big difference. thanks for any & all sugestions . wayne

Depends on the distance you want to sight in for. If say you want a 100 yd zero, then the mid-range height at 50 yds should be between 2"-3" depending on the load. At any rate, 2"-2-1/2" low at 50 yds is way too low and the front sight has to be taken down.....it's probably too low at 25 yds also. Tape some cardboard on the bbl fore and aft of the sight and file the blade down...go slow and take a couple of shots after each filing. Also, is that load what you'll normally be shooting? If not, then develop a new load first and then file the front sight....Fred

More powder=flatter trajectory.
Not always the way to get the best groups however, so we sometimes have to compromise depending upon the intended use.
"Low-and-slow" often works real well for dedicated target shooting, but can be problematic in the field where ranges are not precisely known for each shot.

Not knowing the velocity makes it difficult to determine. There are online calculators, however, you must know the velocity, in order to figure out the drop. But I believe less than an inch would be more like what you should be seeing. Round balls drop a lot, but mostly at distances of 75 yards plus. The difference could be contributed to sight picture, at 50 yards. Might try different style target.

You will probably find one load close to what you are now shooting that is good for 25 yd target shooting and another heavier load somewhere around 65 gr or so that will shoot well @ 50 yds.
Don't do anything to your sights until you get these two loads worked out.

One hole groups at 50 yards is championship level shooting. Take a truck to Friendship, you will need it to haul your medals back home.
Forget sighting at 25 yards, the results will tell you nothing. Get that 50 one-holer on the X and stay there. Practice at 100 yards. I believe you will find the 'apparent' drop much less than you anticipate. The reason is at 50 yards the trajectory may still be rising. In some cases, with the sight picture some rifles can be held center at 25,50 and 100 yards. Leave the file at home until you do more paper punching at 50 and 100.

A lot depends on the height of the front sight above the center line of the bore.

I'd sight in at 50 then see what the 25 looks like. It will be a lot less off than 2". May not be able to see a difference. Most of my long guns shoot one charge at 25 & 50 then another usually 50% more at 100 without changing sight picture.

40 Flint said:

A lot depends on the height of the front sight above the center line of the bore.

I'd sight in at 50 then see what the 25 looks like. It will be a lot less off than 2". May not be able to see a difference. Most of my long guns shoot one charge at 25 & 50 then another usually 50% more at 100 without changing sight picture.

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That is why I qualified my statements with "may", "I believe", etc. Every gun and shooter is individual. The only equalizer is practice. With practice the shooter will instinctively hold for center hits at all ranges. He might center at 25 & 50 and 12 o'clock at 100 and all without changing charges.

A sight picture zeroed at 25 yards should be shooting 3 to 4" higher at 50 yards. It should still be rising at 50 yds.
A zero at 50 or even 75 should give you a good working sight picture at 25, 50, and 100 yds.

Working a center hitting light load at 25 yards can be worked out to hit center at 50 yards working out the muzzle jump of a slower load.
You just have to spend time shooting and keeping good records what your rifles barrel length reacts to with light or heavy loads as well as the granulation used. A light load will hit higher then a heavy load with in a certain distance

Butch

guess i didn't explaine right. 50 gr. 3f goex .445rb .018 patch was only load used. center hold 25yds. & 50 yds. 50yd. shots were 2'' lower than 25yd.shots, i thougth the 50yd.shots should be higher. wayne

Sorry, just trying to help you develop a load that will hold center with the same load at two different ranges.

Sa far as your question, how you hold your rifle and length of the barrel as well as the weight of the rifle will have different vertical impacts.

ramrod 62 said:

guess i didn't explaine right. 50 gr. 3f goex .445rb .018 patch was only load used. center hold 25yds. & 50 yds. 50yd. shots were 2'' lower than 25yd.shots, i thougth the 50yd.shots should be higher. wayne

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Wayne,

Did you use the exact same target and the exact same point of aim at both 25 yards and 50 yards? If either (or both) were different between the two distances, then you may and probably should not consider that 2" drop at 50 yards as "set in stone."

Gus

Wayne,

Something else, if you changed shooting positions between the two yard lines, that also will normally give a "Point of Impact" difference, even if you used the same target and same aiming point at both distances.

Gus

Dane said:

A sight picture zeroed at 25 yards should be shooting 3 to 4" higher at 50 yards. It should still be rising at 50 yds.
A zero at 50 or even 75 should give you a good working sight picture at 25, 50, and 100 yds.

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Zeroing at 25 yards is never a good idea. If you do that you may never know where the poi is at other ranges. Zeroed at 50 yards the ball is still rising at 25 and often has the same poi as at 50. Check out trajectory charts in reloading manuals to understand the concept.