Author Topic: fixed sights?  (Read 13917 times)

Archie Otto

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fixed sights?
« on: April 21, 2014, 05:07:14 AM »
With buckhorn or similar fixed dovetailed sights what process do you use to develop a load and sight in a rifle. 
Do you ever move the sight after the initial sight in?

wet willy

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Re: fixed sights?
« Reply #1 on: April 21, 2014, 05:31:12 AM »
For me, the first step is to determine what the sight picture should be. I make a sketch of the image I want. For some buckhorn sights, you could put the blade in the middle of the "horns," or in the small notch usually found at the bottom of the sight. For others, maybe just put the front blade in the notch even with the top.

If the front blade is too thick and over fills the slot, either increase the slot width or slim the front sight. Your choice. Shoot at least 5 rounds, find the approximate center of the group, and adjust the elevation on the front sight (hope the group is not too high, 'cause that generally means a new, higher front sight).

You can develop a ratio of the sight radius to the target distance and determine how much to file off the front sight and/or drift it or the rear to center the group. I've found it is easier to drift the front rather than the rear. Now try another 5 shots group, but only move the sights 1/2 the distance to center the group. Given the round-to-round dispersion between shots, you are likely close enough for most uses.

Offline smylee grouch

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Re: fixed sights?
« Reply #2 on: April 21, 2014, 05:42:07 AM »
Develop your best shooting load combination using the sight picture that you can see the best. After you know what load is best, then move sights to hit where you want and fix them solidly ( the sights ).

Offline Artificer

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Re: fixed sights?
« Reply #3 on: April 21, 2014, 06:48:41 AM »
Archie,

Had to modify this after reading Wet Willy's post above.  He is absolutely right that you need to figure out what is the best sight picture for you and if you have to change the width of the sight notch or blade as he mentioned. 

The next thing to do is find the Ball/Patch/Lube/Powder  (and Cap if you have a percussion gun) combination that shoots the tightest groups for how you plan on using the rifle.  (Switching brands of caps will often or usually lead to changes in group size.)   Each rifle will have normally two “accuracy” loads, one with just enough powder to get it to fly true and a larger powder amount that will be good for hunting medium to large game.  For example, I have a .45 cal. flint rifle that prefers EXACTLY 42 ½ grains of FFFg for an accuracy load for shooting at 25 to 50 yard targets.  However for a hunting load, it wants 80 grains of FFFg with the same ball/patch/lube combination it prefers.  You don’t really care WHERE on the target the groups hit, but rather what loads make the smallest groups.  Of course if you don’t plan to do much or any target shooting, then go straight to the heavier hunting load.  

An extremely important part of this process is that you use the most stable position you can to get the smallest group sizes and for most of us that means some kind of rest on a bench.  You really need to get as much human error as you can out of the accuracy testing or you will not find the most accurate load/s for your rifle.  Later on you can adjust your sights to move the group where you want them to hit, but that comes after finding the smallest group your rifle can shoot.  

I also most strongly suggest you use a different kind of target than what many people use to obtain the best accuracy load because it allows you to shoot more accurately.  I’m referring to a standard 6 or 8 inch black bullseye on a white or off white target background, BUT with a 1” white circle or square in the center of the Bullseye.   You aim at that 1” white circle or square.  If you can’t find targets like this, then buy the white stick on labels from Office Supply stores and stick them in the center of the black bullseye. What this does is allow your eye to focus better and shoot tighter groups.  OK, I’m not an Optician and can’t explain from a medical standpoint why it works, I just know it DOES work.  

You MUST find the most accurate load from the most stable position for your rifle before doing anything else because then if you don’t shoot groups that small later on, you know it is YOU and not the rifle.  Then you can work on more accurate positions and generally improving your shooting technique.  

OK, after you find the load combination that gives you the best accuracy, what next?   While still shooting from the bench, you should shoot at 25, 50, maybe 75 and 100 yards using the EXACT SAME aiming point.  You NEED to know how much the groups drop or change position on the target at each range.  I most strongly advise measuring how the group changes target position at 50, 75 and 100 yards and writing it down BOTH to get it in your mind and for later reference.  It is also a good idea to record wind velocity and direction, temperature, humidity, how sunny or cloudy it is, etc., etc.   The MORE you write down, the better it will be for later use and the better you will learn that rifle.  

NOW that you have the most accurate load in your rifle and you know how the groups will change position at different ranges, you can begin to think about adjusting your sights, BUT it is not quite time to do that.  

OK, this post is running long, so I will go into Part II on the next post.
Gus
« Last Edit: April 21, 2014, 07:02:42 AM by Artificer »

Offline Artificer

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Re: fixed sights?
« Reply #4 on: April 21, 2014, 08:48:55 AM »
Archie,

How are you going to shoot the rifle most often?  If you plan on shooting in muzzleloading competition, many if not most times that means shooting from the Offhand position.  Even if you mainly plan on using the rifle for hunting, than I suggest it is best to do it in the offhand position as well.  For MOST people and rifles, the group will move from where you shot the rifle off the bench.  This is NORMAL and to be expected, so don’t be surprised at all when it happens. 

Before you go moving the sights, you really should shoot three shot groups to ensure you are not changing the sights off a single shot that is not really representative of where the rifle is shooting.  Normally it is best to shoot the group at 25 yards.   If you jerk the trigger or drop the muzzle or do any error on one of the shots, ignore it and shoot another shot.  You need three well aimed shots in the group.   Figure out where the center of the three shot group is and that is what you want to move to change the point of impact. 

It is easier to adjust windage (how the group hits to the left or right of center of the target) so that is normally what we adjust first. 

OK, do you move the Rear Sight, Front Sight or Both? 
It all depends on your eyesight and how the rifle shoots.  Slight left or right adjustments may be done by moving he rear sight IN THE DIRECTION you want the center of the group to move.  With the front sight centered on the barrel, this is normally how most side to side or windage adjustments are made.  However, if you have to move the rear sight way over to the right or left, then it is best to move the front sight as well.  A good many original rifles have the front sights a little to the right or left of center.

Moving the front sight to change group position side to side is DIFFERENT than moving the Rear Sight.  The Front Sight is moved in the opposite direction of where you want to move the groups.  IOW, if you want to move the group to the left, you have to move the Front Sight to the right.  Now THAT is downright confusing, I know.  GRIN.  As a National Match Armorer, I have forgotten how many hundreds if not thousands of times I have moved Front Sights on M1 and M14 Rifles.  The BEST way to remember it is you move the front sight towards the direction of the group, while you move the rear sight into the center of the bullseye.

After you get your group centered “side to side” for windage, then you start to adjust for elevation.

However, it’s very late and will have to type more later.
Gus

Offline PPatch

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Re: fixed sights?
« Reply #5 on: April 21, 2014, 03:52:12 PM »
Gus;

Your explanation(s) are most excellent and very clear. Thank you. I suggest that this material be put in the tutorial section.

dp
Dave Parks   /   Quis custodiet ipsos custodes?

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Re: fixed sights?
« Reply #6 on: April 21, 2014, 06:06:51 PM »
Gus;

Your explanation(s) are most excellent and very clear. Thank you. I suggest that this material be put in the tutorial section.

dp

Dave, 

Thank you for the kind words.  I joke that having spent a career on Rifle Ranges, some things stuck, if nothing more than through Osmosis.  Grin.  I enjoy passing on things I've learned by way of thanks for things I learn on this forum.  If the Moderators feel it is worthy of being a Tutorial, then I would be honored.
Gus


Offline Artificer

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Re: fixed sights?
« Reply #7 on: April 21, 2014, 07:30:45 PM »
Before going further, perhaps it is best to write about how to move rear and front sights right or left.  

First one needs some kind of drift or punch against the side of either sight that is struck by a hammer to move the sight.  It is EXTREMELY important to use a drift punch that is softer or at least no harder than the material of the sight, so you don’t ding up the sight with the drift punch.  Sometimes one can use a hard wood dowel or Nylon Punch for this, but many times one needs something stronger than that and Brass or Bronze are normally the materials of choice.  

There is no need to buy a set of Brass Gunsmith’s Drift Punches to move sights.  If you know someone who works in a machine shop, perhaps they can get you a four or five inch length of ¼” Diameter Brass Rod.  If not, go to a Boat/Marine store that carries supplies.  I bought a 4” long, about ¼” diameter, round head domed Brass bolt (like a carriage bolt) years ago from such a store and it is my favorite punch for moving sights and other things.  After filing off the machine threads, I filed the end to a rectangular shape and it is just the ticket to move sights.   Then I filed a flat on the rounded dome and that is where I hit it with a brass or steel hammer.  

Oh, another nice thing about using a brass or bronze drift punch is that you normally can’t see where it hit on a brass front sight.  On an iron or steel rear sight, it leaves a little “wash” of brass color, but that can easily be cleaned off using one of the modern bore solvents designed to remove copper.  Put some solvent on a Q Tip and rub hard on the brass “wash” and it will take it off without harming the finish on an Iron/Steel sight.  Just make sure you oil it afterwards so it doesn’t rust.  

When moving a Front Sight, it is EXTREMELY important you DO NOT hit the blade as you will bend, crack or even bust the blade off the dovetail base.  Yep, I’ve seen folks do that too many times and that’s why I mention it.  It is best to hold the gun in a padded vise, but at the range maybe you can get someone to hold the gun for you or lay the gun down on a pad on it’s side.  You place the drift punch as close to the bottom of the dovetail sight base as you can and keep the face of the drift punch as even as you can with the dovetail.  (You may need to file the drift punch so it is a smaller than the side of the dovetail or turn the punch so the smaller side of the rectangular shape is against the dovetail.)

Unless one is a Rifle Builder, most of us won’t know how tight the sights are in their dovetails when we go to adjust the sights.   So when you carefully place the drift against one side of the front sight dovetail base, tap it lightly at first to see if it will move the front sight.  If not, tap it a little harder.  Keep trying to tap it a little harder each time until it just starts moving the sight base.

Something one may not think about is how can you tell how far you moved the sight?  I normally use a 6” precision Machinist’s Rule (Steel Ruler) but most folks won’t have one of those.  All you really need for the job is a Very Fine Tip Black Permanent marker.  You draw one line on the sight base close to the middle and extend it onto the barrel.  That way you can see how much you move the sight base each time and sometimes it will show you where to drive it back if you went too far or in the wrong direction.  (Yep, that is bad experience talking.  Grin.)  When you are done moving the sight, some bore cleaner or Acetone will clean off the black mark and then oil it to ensure the barrel and sight (if Iron or Steel) doesn’t rust.  

OK, so how far do you move a sight?  There are mathematical formulae for different calibers that talk about moving the sight a fraction of an inch to move the strike of the bullet one inch at 100 yards, but to be honest, they are at best only a guide to moving sights.  In the hundreds, if not thousands of front sights I’ve moved over the years, I found it wasn’t necessary or even much useful to use those formulae.  There are too many differences in the way each shooter see’s the front sight.  What I suggest is try moving a sight maybe 1/64” or at most 1/32” and shoot the rifle to see how far it moved the group.  Then adjust a little and shoot until you get the group centered on the bullseye at 25 yards.  This works best for folks who shoot in 25 and 50 yard matches and is a good starting point for longer range matches or hunting.  You may find sights so adjusted will be off a little side to side at 50 yards, and if so, you just “hold” the sights or aim a little off center when you shoot, to center the group at 50 yards or further.  

I wasn’t sure if I should add this last information, but decided to do so in case one has a RARE occurrence of a bore that is not well centered in the barrel.  Most folks will never run into this, though.  In such a case after one centers the group at 25 yards, the group will be WAY off to the right or left at 75 or 100 yards quite a few inches.  In the old days as today to keep this from happening, gunsmiths and barrel makers bent the barrel to ensure the bore was straight.  However in rare examples, sometimes the barrel would still shoot way off to the right or left.  So what they did was take the barrel out of the stock, bend it and shoot and bend and shoot until it shot straight.   I DO NOT recommend most people try this today because bending barrels is an Art Form that even many or most gunsmiths don’t know how to do properly.  Normally it is best to return the barrel for replacement when this happens.

There is another option that people have done with muzzleloaders and modern rifles with fixed sights when a rifle is centered at 25 yards, but shoots 6 to 8 inches or more off at 100.  Let’s say it is off that far to the right at 100.  They move the sights so the group is centered a little more to the left at 25 yards so the group at 100 yards is not so far off to the right.  It’s not great for shooting matches at 25 yards, but it normally is good enough for hunting small game like squirrels or rabbits when you aim a little off center at short ranges.  However, on larger game like Deer, you aim center all the way to 100 yards as there is an 8 to 10 inch killing zone on deer and your group will be inside that zone from 25 to 100 yards.    
Gus

Modified to add:  There is no way to be certain sure how they adjusted sights in the original time period, but I THINK they did it similar to the last paragraph as it made it easy for fast shots while hunting.
« Last Edit: April 21, 2014, 08:12:56 PM by Artificer »

Offline JBJ

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Re: fixed sights?
« Reply #8 on: April 21, 2014, 07:42:53 PM »
My memory being what it is, I only try to remember a simple "rule" - FORS - when it comes to adjusting iron sights.
If I need to shift impact using the front sight, move the sight opposite to that direction; FO = Front opposite. Shifting the point of impact using the rear sight, the rule is to move it in the same direction; RS = rear same. FO + RS = FORS!
J.B.

Offline smylee grouch

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Re: fixed sights?
« Reply #9 on: April 21, 2014, 07:45:41 PM »
When I go out to shoot a gun for the sight-in, I usualy bring a couple of the Quick-clamps with the rubber pads on the jaws with me. They wont do the job of a padded vice but still hold the gun well enough to do some front sight filing and moderate sight drifting.

Offline Artificer

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Re: fixed sights?
« Reply #10 on: April 21, 2014, 07:49:55 PM »
When I go out to shoot a gun for the sight-in, I usualy bring a couple of the Quick-clamps with the rubber pads on the jaws with me. They wont do the job of a padded vice but still hold the gun well enough to do some front sight filing and moderate sight drifting.

That is an EXCELLENT suggestion.  I take a small screw on vise and use leather and cloth pads in it.  The range it opens is less than 2" to clamp it onto a table or bench top, but I normally can find a wood bench top that is smaller than that to screw it on.  However, it that were not available, I would use your excellent suggestion. 
Gus

Offline Artificer

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Re: fixed sights?
« Reply #11 on: April 21, 2014, 07:53:28 PM »
My memory being what it is, I only try to remember a simple "rule" - FORS - when it comes to adjusting iron sights.
If I need to shift impact using the front sight, move the sight opposite to that direction; FO = Front opposite. Shifting the point of impact using the rear sight, the rule is to move it in the same direction; RS = rear same. FO + RS = FORS!
J.B.

J.B.

That's another good way to remember it.  It doesn't really matter how one remembers, just so long as one does remember.  GRIN.
Gus

Offline JBJ

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Re: fixed sights?
« Reply #12 on: April 21, 2014, 09:12:52 PM »
Gus,
The remembering part seems to be harder each year - I seem to recall.
J.B.

Offline LRB

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Re: fixed sights?
« Reply #13 on: April 21, 2014, 11:00:57 PM »
Quote" I wasn’t sure if I should add this last information, but decided to do so in case one has a RARE occurrence of a bore that is not well centered in the barrel.  Most folks will never run into this, though.  In such a case after one centers the group at 25 yards, the group will be WAY off to the right or left at 75 or 100 yards quite a few inches.  In the old days as today to keep this from happening, gunsmiths and barrel makers bent the barrel to ensure the bore was straight.  However in rare examples, sometimes the barrel would still shoot way off to the right or left.  So what they did was take the barrel out of the stock, bend it and shoot and bend and shoot until it shot straight.   I DO NOT recommend most people try this today because bending barrels is an Art Form that even many or most gunsmiths don’t know how to do properly.  Normally it is best to return the barrel for replacement when this happens." Quote

 Gus, are you saying a horizontal bend in a barrel makes a bullet curve in flight?
« Last Edit: April 21, 2014, 11:02:27 PM by LRB »

Offline Artificer

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Re: fixed sights?
« Reply #14 on: April 22, 2014, 02:40:16 AM »

Gus, are you saying a horizontal bend in a barrel makes a bullet curve in flight?


Good question and the short answer is that it does not.  What a horizontal bend does is change the position of the muzzle left to right, so when the ball leaves the muzzle, it would then be further left or right than before it was bent. 

Bending barrels to change where the shot or bullet hits is mostly used today in centerfire shotguns and sometimes .22 rimfire rifles, but not usually in centerfire rifles. 
Gus

Offline LRB

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Re: fixed sights?
« Reply #15 on: April 22, 2014, 01:13:42 PM »
  Yes, but if sights are set for center POI horizontal, windage, at 100 yrds, the POI and sighting hold is not going to be different at any distance between 0 and 100 yrds. There is no sight correction for 25yrds, 50 yrds, or any other distance in between, straight or bent barrel. The bullet flies in a straight line from the muzzle, with exception of elevation. The same sight picture is used for any distance in between with no left or right corrections. There is nothing to correct. Groups do not change position at different ranges except for elevation, or beyond the sight setting in which case is due to error in setting being magnified by more distance.  
« Last Edit: April 22, 2014, 01:21:40 PM by LRB »

Offline Artificer

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Re: fixed sights?
« Reply #16 on: April 22, 2014, 11:25:48 PM »
LRB,
 
What you are missing is that after the barrel is bent so the ball flies straight from the muzzle in a new direction, is that the sights are reset to take advantage of that change in direction of the barrel sending the ball in a different direction.  (In a Longrifle, the forearm would have had to have been steam or water bent to match the new bend in the barrel if the barrel was bent enough so it would not slip back into the forearm.)  On a half stock gun, it is easier to bend the barrel when there is not a full length forearm.

As an extreme example, let's say you have the front sight all the way towards the right side of the barrel and the rear sight is all the way to the left side of the barrel and your ball is STILL hitting too far to the right at 100 yards.  Besides replacing the barrel, how could you fix that?  The answer is to slightly bend the barrel to the left and then adjust the sights closer to center on the barrel if the ball now flies far enough closer to center on the target to move the sights..
Gus.




Offline LRB

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Re: fixed sights?
« Reply #17 on: April 23, 2014, 02:30:42 PM »
  You kinda skirted the issue as you often do. The discussion was the sight settings and POI at different rages between 0 and 100yrds. Sights set for a center strike at 100yrds do not have to be manually or visually corrected for a 25 yrd shot. The bullet will strike center from muzzle to the 100yrds with exception of elevation deviation.  I've bent barrels. It is not rocket science, and a LR or full stock does not have to be  steam bent for the barrel to fit back into it. Bending to straighten a slight deviation in order to better center sights usually only requires a fraction or so, and a LR or trade gun fore end is so thin as to not be a problem. For one to have to correct windage at 25 yrds, with sights set for 100yrds, the ball would have to be curving in flight. That only happens from wind forces. Elevation is a different concern.

Offline Artificer

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Re: fixed sights?
« Reply #18 on: April 23, 2014, 06:16:12 PM »
“Kinda skirted the issue as I often do?”

Let me go back to an earlier post where I wrote, “I wasn’t sure if I should add this last information, but decided to do so in case one has a RARE occurrence of a bore that is not well centered in the barrel.  Most folks will never run into this, though.  In such a case after one centers the group at 25 yards, the group will be WAY off to the right or left at 75 or 100 yards quite a few inches”

So in my last post, I gave an example where a gun is sighted in at 25 yards and is way off at 100 yards and no further room to adjust with the fixed sights.  THAT is skirting the issue as I often do?  Of course it isn’t.  I was speaking to something that I had already written was a “RARE occurrence” and that “Most folks will never run into this, though.”  

As to not needing to steam or water bend the forearm, I already wrote that would only be necessary if the bent barrel would not slip back into the forearm after the barrel was bent.  

Then you wrote,  “For one to have to correct windage at 25 yrds, with sights set for 100yrds, the ball would have to be curving in flight.”  

You do realize that is something entirely different than I was discussing, don’t you?  At least I hope so.  You give an example where the sights are already set at 100 yards and that means the deviation in the bore to outside barrel contour can not be off that much in that barrel or else you would not be able to set the sights at 100 yards.    

I gave an example where the bullet impact was way off at 100 with no sight adjustment left , or IOW where one could not set the sights at 100 yards.  This would demonstrate a RARE occurrence where the bore is off alignment with the outside of the barrel and something most people will never run into.  That is why I hesitated to even bring it up.

Gus
« Last Edit: April 23, 2014, 08:29:28 PM by Artificer »

Offline Artificer

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Re: fixed sights?
« Reply #19 on: April 23, 2014, 07:17:36 PM »
Oh, and as far as bending barrels is not rocket science, I agree it is not rocket science, but it does require some care and knowledge that many people do not have.

I have seen results of people who did not have knowledge or used much care and then damaged barrels and that included octagonal rifle barrels (both repro and one original barrels) and one original P1858 Enfield.  Other smiths I've talked to have mentioned they have seen it in repro Uncivil War Rifle Musket and Rifle barrels.  Now even a 3 band Rifle Musket barrel has more steel in the barrel than many fowler barrels, so the persons who damaged those barrels obviously should have gotten more knowledge and used more care or should not have tried to bend those barrels.  

So I normally don't encourage amateurs to try bending barrels and especially not in a thread where the original poster is asking how to sight in a barrel.  
Gus
« Last Edit: April 23, 2014, 07:28:12 PM by Artificer »

Offline LRB

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Re: fixed sights?
« Reply #20 on: April 23, 2014, 09:07:47 PM »

"There is another option that people have done with muzzleloaders and modern rifles with fixed sights when a rifle is centered at 25 yards, but shoots 6 to 8 inches or more off at 100.  Let’s say it is off that far to the right at 100.  They move the sights so the group is centered a little more to the left at 25 yards so the group at 100 yards is not so far off to the right.  It’s not great for shooting matches at 25 yards, but it normally is good enough for hunting small game like squirrels or rabbits when you aim a little off center at short ranges.  However, on larger game like Deer, you aim center all the way to 100 yards as there is an 8 to 10 inch killing zone on deer and your group will be inside that zone from 25 to 100 yards.   
Gus"

Why would you not just set the sights for center at 100? Then you can hold dead center at 25 or any range in between 0 and 100. I assume we are discussing an accurate rifle and load. Now, if one has run out of sight adjustment room, I can understand doing as you suggested, but that would really be the time to bend the barrel, or have it done. What am I missing here? I believe I am just misunderstanding your explanations, but am not sure. By the way, years ago it was common and even expected that a bore was not centered in a ML barrel. The makers put their mark on the flat that would affect elevation only. The builder usually knew to position this mark to the bottom of the barrel when inletting, or sometimes on top. Am pretty sure Douglas did this. Dixie Gun Works barrels were this way, and probably Numrich Arms.

Offline Artificer

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Re: fixed sights?
« Reply #21 on: April 23, 2014, 09:59:15 PM »
Archie,
Before one begins adjusting your sights for elevation, I suggest it is a good idea to pull out one’s recorded notes on how far one’s groups moved or dropped where they hit on targets from 25 yards to 50, maybe 75 and 100 yards and using the same aiming point at the white 1” circle or square in the center of the bullseye on each target.  Hopefully you will have notes on this for both your lighter powder charge target loads along with your heavier powder charge for your hunting load.  You may find the Patched Round Ball (PRB from now on) groups do not drop as much with the heavier charge hunting load as with the lighter target loads.  The difference can be small or noticeable depending on the difference in ranges fired, powder charges, the caliber of the rifle and the rifle itself. 

For example, years ago I owned an original circa 1850, .36 caliber percussion half stock rifle.  I was not concerned with a heavier hunting load as I only shot that rifle in 25 and 50 yard competition.  (Oh, and any small critter I was going to shoot with a .36 caliber rifle would not notice the difference in the lighter accuracy load.)  I joked that rifle shot like a laser beam with the best accuracy/target load and there was so little drop between 25 and 50 yards, I barely had to hold higher to hit the center of the 50 yard bullseye compared to my 25 yard sight in.   There was also so little difference in windage deviation between 25 and 50, I just held slightly off for it unless the wind was blowing hard and then held off more.  I wanted to keep the 25 yard sight in for my sight adjustment because we shot at strings held down by weights and split the ball on the axe blade at that distance, besides bullseyes and other types of target.  At 50 yards we shot at bullseyes or other targets that were easier to hit than strings or axe blades.

Many people who only shoot 25 and 50 yard matches find there is so little difference in bullet drop at 50, that they just use the 25 yard sight in for both and only hold a little higher when aiming at 50 yards.  However, when you go to longer ranges, there is more bullet drop with a PRB.

Here is an example of bullet drop for a .50 Cal. PRB starting out at 1900 FPS at the muzzle and that is normally a hunting load.  (I got this from a post DPhariss posted in the “Rifle Accuracy 1776” thread from this forum.)

Range     Drop in inches
0          0
25         0.41
50         1.61
75          3.82
100         7.32
125               12.44
150               19.48

So if one sighted one’s rifle at only 25 yards for hunting, the 7.32” drop at 100 will just keep you inside the 8 – 10 inch killing zone for deer, but you will be outside the zone at 125 yards which may only cripple the deer.  So most folks sight in their rifles for hunting at a further distance.

On the first chart in the following link, it shows the trajectory of a .50 caliber ball at 1800 FPS when sighted in at 125 yards.  Notice how the ball does not rise or fall  more than 3.5” from 0 to about 135 yards?  What is important about that is on a deer sized target (with the rifle sighted in at 125 yards at the listed bullet speed), you can aim dead center on the 8-10” killing zone of a deer anywhere from 0 to 135 yards and the ball will land in the killing zone.  (The ball will actually strike higher or lower in the killing zone than your dead center aiming point at different ranges inside that 135 yards, but still inside the killing zone.)    IOW, you don’t have to worry about aiming higher or lower anywhere along that distance to stay inside the killing zone.  Some folks refer to this as the “Point Blank Range” for hunting and find it is the most useful way to sight in a rifle for hunting.
http://www.whitemuzzleloading.com/long_range_muzzleloading.htm

Now, one can’t completely go off any chart when sighting in a rifle.  The most accurate hunting load for your rifle may give more or less velocity than listed in a chart.  That is why it is good to shoot your rifle out to 100 yards with your heavier charge hunting load and farther if possible, if you plan on hunting with it and record EXACTLY how much the groups drop at each range.  Then you can work out the best range to sight in your rifle to get the “Point Blank Range.” 

The following link explains in much more detail about doing this and should help you.
http://home.insightbb.com/~bspen/trajectories.html
Gus

Offline Artificer

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Re: fixed sights?
« Reply #22 on: April 23, 2014, 11:10:52 PM »

Why would you not just set the sights for center at 100? Then you can hold dead center at 25 or any range in between 0 and 100. I assume we are discussing an accurate rifle and load. Now, if one has run out of sight adjustment room, I can understand doing as you suggested, but that would really be the time to bend the barrel, or have it done. What am I missing here? I believe I am just misunderstanding your explanations, but am not sure. By the way, years ago it was common and even expected that a bore was not centered in a ML barrel. The makers put their mark on the flat that would affect elevation only. The builder usually knew to position this mark to the bottom of the barrel when inletting, or sometimes on top. Am pretty sure Douglas did this. Dixie Gun Works barrels were this way, and probably Numrich Arms.



LRB,

I was typing the post above and posted it, before I read this post of yours.  

Archie did not mention how he was going to use the rifle, so the way to sight in would be different according to what targets and what ranges he would shoot.  

As I tried to explain in my recent post above, if one is going to shoot competition at 25 yards where you have to cut a taught string with a ball or split a ball on an axe blade, then I suggest it is preferable to sight in the rifle at 25 yards for that precise of shooting.  Sighting in at 100 yards may (if not may often) cause one to use more sight adjustment for windage that would cause one to miss a string or axe blade at 25 yards.  

Since Archie did not reply how he was going to use the rifle, I thought it best to explain how it would be best to sight in depending on how he was going to use it.  A lot of people new to muzzleloading don’t know these things.

Now perhaps I spent too many years being the “Instructor of OJT’s” (Apprenticeship Instructor) at the RTE Shop at Quantico teaching Marines to become NM Armorers and in teaching new things to others in the shop and other Marines in other places.  I never knew what students knew or didn’t know and it varied a lot from person to person.  So I always told students that I would start from “ground zero” because I did not want some students to miss things other students already knew OR might be important to them and they did not know to ask about it.  I don't pretend to know everything, of course, but always try to impart as much as I can.  

I’ve been around Muzzleloaders since before I first started competing at Friendship in 1974 on the Primitive range.  So, yes, I learned years ago to look for the mark you mentioned used to be commonly placed on barrels.  Even with that mark on some barrels, it was “Old Hat” even then to look for Bore Run Out on muzzleloading barrels and place the end of the barrel where the bore was more centered at the muzzle.  

Good point you made bringing it up here, as folks new to muzzleloading probably don’t know it, though.  

Gus
« Last Edit: April 23, 2014, 11:22:25 PM by Artificer »

Offline LRB

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Re: fixed sights?
« Reply #23 on: April 23, 2014, 11:45:32 PM »
  Well Gus, sadly, I did not misunderstand you. Take care, and carry on.   :)

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Re: fixed sights?
« Reply #24 on: April 24, 2014, 01:27:24 AM »
Very well, have a good day.
Gus