Rifle shoots high?

[Semisane]

You nailed it Twisted. With his load the trajectory with a 100 yard zero should be something like that shown in the table below.

The ball crosses the line of sight at about 4 yards from the muzzle. It remains above the line of sight (with a maximum rise of about 3.6 inches at about the 50 yard mark) until it hits zero at 100 yards. At 100 yards and beyond it drops below the line of sight.

And I agree, he should get the gun shooting one hole groups at 25 yards before futzing with the sights. It's of no importance where those groups are on the target. Group size is what's important. Once he has a load that's shooting one hole groups at 25 he can start worrying about where that group is on the target.

Yards...Velocity...Drop
0............1750........-0.5
2............1725........-0.3
4............1701.........0.0
6............1670........+0.2
8............1640........+0.5
10...........1618........+0.7
15...........1548........+1.2
20...........1483........+1.7
25...........1424........+2.2
30...........1366........+2.6
35...........1315........+2.9
40...........1265........+3.2
45...........1220........+3.4
50...........1180........+3.6
75...........1042........+3.1
100...........951.........0.0
125...........875........-6.1
150...........810........-15.8
175...........749........-30.1
200...........690........-50.0

 

[Semisane]

Yea BUT WHAT IF YER USING 2F? :hmm: :shocked2: :redface: :slap:

Sorry

He must not use 2F in a .45 azmntman. Doing so would affect the balance of the universe and cause Halley's Comet to arrive in 2063 rather than 2061. This is serious stuff ya` know!

 

[smo]

Would the Mississippi River run backwards as well ? :haha:

 

[smo]

I was always taught that a ball or bullet would be dead or point blank at two separate times . Once as it crosses the line of sight from below the sight plane then when gravity takes over and it re crosses the sight plane on its way down. :stir: :stir: This is going to get good it looks like :wink:

Well that's generally true smo. But the first crossing of the line of sight is so close to the muzzle as to me virtually meaningless for the purpose of sighting in a rifle (it's about ten yards or less). Unless of course you plan to sight in for very short distances. :grin:
. It would not be virtually meaningless if shooting at a very small target as you stated....say the edge of a playing card or maybe a tooth pick at 8 to 15 yards .
However, it's not always true. Note that in the case of the OP's ballistics, because the zero point is a short 30 yards the ball does not rise above the line of sight. It just reaches it before beginning the drop

Agreed it would still be rising which is why it would be high at 50 yards :hatsoff:

 

[Semisane]

However, it's not always true. Note that in the case of the OP's ballistics, because the zero point is a short 30 yards the ball does not rise above the line of sight. It just reaches it before beginning the drop.

Agreed it would still be rising which is why it would be high at 50 yards :hatsoff:

You guys are unbelievable. If the the ball is hitting zero at 30 yards, it cannot possibly rise above the line of sight beyond 30 yards.

Please go out and sight in any round ball rifle you want, with any powder charge you desire. Sight it in for dead on at 30 yards. Then, without adjusting the sights and using the same sight picture on the bull, shoot a 50 yard target. You need not report your results back here. I know what they will be.

 

[Semisane]

Well guys, in about ten minutes I'm heading out to the hunting camp for an evening with the guys - boiled crabs and some much needed beer.

Chat with `ya later. :v

 

[Billnpatti]

And I agree, he should get the gun shooting one hole groups at 25 yards before futzing with the sights. It's of no importance where those groups are on the target. Group size is what's important. Once he has a load that's shooting one hole groups at 25 he can start worrying about where that group is on the target.

I agree 100% and would highly recommend www.blackpowderrifleaccuracy.com

 

[mooman76]

I know it's a completely different rifle but same principal. I sight in my .06 at 25y dead on. It shoots 1" high at 100y and dead on again at 200y.

I think 6" high is more than it should be. Maybe the first 3 at 30 were from a cold gun and the others are from fouled but 3 shots each isn't good enough for certainty. If it's normal for his gun then arguing about it is really pointless either way.

 

[longcruise]

I think the previous owner shot the rifle with 35 or 40 grains and filed the front sight to POI on a squirrels eye at 25 to 30 yards. Our OP hopped it up and raised the POI about 2 or 3 inches at 25 or 30 yards. That much difference at 30 will easily raise the POI at 50 as his target shows.

My conclusion; there is nothing wrong with the gun. He should leave the sights alone until he arrives at a load combination that works and then replace the front sight If needed to sight it in.

 

[hanshi]

something is definitely awry with Flintlock's situation. Without getting into charts/physics/etc, I can confirm that 70 grains of 3F in my .45 with a .440" ball at about 1750fps, when sighted in 1" high at 25 yards is higher than that at 50 yards. There is no way, however, barring something funny going on, that such a shot will be 5"-6" high at 50. My rifle is comfortable at roughly 1" (or maybe 2") high at 50.

 

[54ball]

Flintlock 1776 needs to shoot his rifle some more. A lot of this can be sight picture and hold.

 

[Twisted_1in66]

Process is the same regardless of whether you are using 2f or 3f. I personally don't know of anyone who uses 2f in a .45 caliber rifle. Not saying it's never done, but it would be very unusual to do so. Smallest recommended bore for 2f is .50 cal. I have two .50 cal rifles and use 3f in both of them because that's what they like best. It's fairly common to see 2f used with .54 caliber and up and virtually always with the smoothbore muskets (.69 cal. and .75 cal.)

2f has larger granules and less surface area so it burns more slowly than 3f and as a result builds up pressure more slowly. I would not even include it in the variables for a .45 cal. rifle. As far as ballistics go, it doesn't matter what granulation you are using. What matters on what muzzle velocity you get out of it.

Twsited_1in66:thumbsup:
Dan

 

[hanshi]

Flintlock 1776 needs to shoot his rifle some more. A lot of this can be sight picture and hold.

I think that's probably the root cause of his problem.

 

[smo]

However, it's not always true. Note that in the case of the OP's ballistics, because the zero point is a short 30 yards the ball does not rise above the line of sight. It just reaches it before beginning the drop.

Agreed it would still be rising which is why it would be high at 50 yards :hatsoff:

You guys are unbelievable. If the the ball is hitting zero at 30 yards, it cannot possibly rise above the line of sight beyond 30 yards.
Z
Please go out and sight in any round ball rifle you want, with any powder charge you desire. Sight it in for dead on at 30 yards. Then, without adjusting the sights and using the same sight picture on the bull, shoot a 50 yard target. You need not report your results back here. I know what they will be.

: rotf: :rotf: I've already done that that's how I know what it will do :blah: I sighted in with 80 grns of ffg in my 54 dead on at 25 yards. At 50 it's approx. 4 inches high. :wink: there is no way possible if a rifle is sighted in at 25 or 30 yards that the bullet / ball can go from below the line of sight to above the line of sight then gravity pull the ball/ bullet back down to the line of sight in that short of a distance........ :slap: the ball/ bullet is still on the rise from below the line of sight that is why it will still be high at 50 yards. I don't know of any balisitics tables or computer program that would not agree with that. Of course Im not much on tables or computer programs when it comes to shooting.

 

[jethro224]

there is no way possible if a rifle is sighted in at 25 or 30 yards that the bullet / ball can go from below the line of sight to above the line of sight then gravity pull the ball/ bullet back down to the line of sight in that short of a distance........

Substitute powders? :idunno: :stir: :haha:

 

[jethro224]

...my .45...when sighted in 1" high at 25 yards is higher than that at 50 yards.


There is no way, however, barring something funny going on, that such a shot will be 5"-6" high at 50.

Take a good long look at those paper plates again. Standard paper plates are 9". The difference in those groups is NOT 6"! If it were, the high group would have to be an inch and a half off of the plate.

 

[Grumpa]

I just picked up on this thread a few minutes ago.

The Original Poster/OP has been conspicuously absent since his original post.

Nowhere does he say that he was zeroed in at 30 yards.

We don't know what he zeroed in for, or even if he knows what he's zeroed in for.

The rifle is, in fact, new to him. All we can gather from the post is that his rifle shoots "minute of deer" out to 50 yards.

I don't know of anyone other than maybe a squirrel hunter, who would zero to 30 yards, and they wouldn't be loading 70 grains of 3f.

We just don't have enough information to warrant all this discussion, and the OP's problem probably has nothing to do with the trajectory of his ball.

 

[Dane]

Semisane,

By your own table, with a 100yd zero, the ball is +2.6" @30yds, and 3.6" @50yds. This is what we've been saying all along. Am I missing some obscure point here?
Maybe we should just agree to disagree, and move on to something more important !?!?!

 

[mooman76]

...my .45...when sighted in 1" high at 25 yards is higher than that at 50 yards.


There is no way, however, barring something funny going on, that such a shot will be 5"-6" high at 50.

Take a good long look at those paper plates again. Standard paper plates are 9". The difference in those groups is NOT 6"! If it were, the high group would have to be an inch and a half off of the plate.

I measured a paper plate and 4" high is more like it but more testing is needed.

 

[Semisane]

I've already done that that's how I know what it will do :blah: I sighted in with 80 grns of ffg in my 54 dead on at 25 yards. At 50 it's approx. 4 inches high.

You're simply operating on a belief that's not true smo.

It's reasonable to assume your 80 grain load produced a velocity of around 1550 fps. If
you were truly sighted in "dead on" at 25 yards, your trajectory would be something like this.



If you were hitting 4 inches high with the same sight setting at 50 yards you were looking through the sights differently when shooting at 50 yard target than you were when shooting the 25 yard target.