POI moves with same load ...

[Sparkitoff]

First, this isn't a complaint, per se. This is particular to 2 flintlock rifles as I haven't had it happen with my 1 percussion rifle. What happens is the rifle is sighted in just right. Within 10-dyas of that range session I used it on a hunt and made a shot exactly where I aimed. Several weeks, or months later I re-visit the range, use the identical load and components and the group has moved somewhat. For instance, last session the groups was very good and dead-on at 100-yards. I even took a picture of the pretty little group. Today, the same rifle, load components, even the same paper target at the same range - and the group is 3-inches high. No, the sight is not loose at all and it has a set screw so it is not likely that it accidentally moved. I can think of 3 "things" that could be different. 1) outside temperature 2) powder is a few weeks or months older 3) patches are not as "fresh" as they were a while back.

Does anyone else experience this? Is there a likely cause or a combination of causes? What do you think?

 

[Crow-Feather]

What you need to add is the type of powder, brand name and model of rifle, is the complete rifle stock sealed? Half stock or full stock? From a rest or off hand? Patch material and thickness?

 

[Carbon 6]

Assuming that you don't have a broken adjustable sight and that you are not removing the barrel from the stock when cleaning, only one thing remains, The shooter.
It is very common for people to shoulder a gun differently from session to session. left right deviations usually mean the shooter is placing the butt in the wrong spot on his arm or shoulder. Up-down deviations mean the shooter is placing his head in a different spot or isn't replicating the same sight picture. An improper LOP can also cause problems for some shooters.
it is extremely helpful to take a buddy with you to the range, if they experience the same problem with your gun then it is likely the gun that is the problem, if they don't it's you.
People are far too quick to dismiss themselves as the problem.

 

[Carbon 6]

I can think of 3 "things" that could be different. 1) outside temperature 2) powder is a few weeks or months older 3) patches are not as "fresh" as they were a while back.

Temp shouldn't be an issue unless the differential is extreme and you are shooting long distance.
Powder shouldn't matter if it's real black and properly stored. some of the ascorbic acid powders may be affected.

Fresh patches ? I don't know what you are shooting but I am a strong believer in not pre-lubing patches. Did you examine the patches for burnout ?

 

[Sparkitoff]

So, the rifle is custom, 1/2 stock (more like 2/3 stock), sealed and bedded. I do not remove it for cleaning. There is one wedge key that is tight and hasn't moved. Powder is Goex FFFg stored inside the house in original plastic canister. Patches are pillow tick strips cut at muzzle, previously treated with 7:1 water/ballistol, dried and rolled up in a sealed container until use. Patches were not burned, no holes just the rough edges and discoloration but could have been reused. Same box of balls. Shooting from a rest, bag at the wedge key, small bag that grip hand is resting on.

 

[Art Caputo]

I have experienced this when I first started shooting flintlocks, and believe it may be caused by a couple of factors. Inconsistency with rifle hold, and/or the flintlocks potential for variable ignition, either of which can effect accuracy compared to the percussion lock. Once I started paying careful attention to a consistent hold, and, the loading, sparking, and priming process, my results Improved and became comparable to the those achieved with my percussion rifles. Not sure this is your issue, but it may be worth considering.

 

[Carbon 6]

So, the rifle is custom, 1/2 stock (more like 2/3 stock), sealed and bedded. I do not remove it for cleaning. There is one wedge key that is tight and hasn't moved. Powder is Goex FFFg stored inside the house in original plastic canister. Patches are pillow tick strips cut at muzzle, previously treated with 7:1 water/ballistol, dried and rolled up in a sealed container until use. Patches were not burned, no holes just the rough edges and discoloration but could have been reused. Same box of balls. Shooting from a rest, bag at the wedge key, small bag that grip hand is resting on.

Sounds like you have eliminated the gun related variables. Like I said take a buddy with you the next couple of times and see if the point of impact shifts for them too. If it does then we missed something, if it doesn't then it's definitely you.

 

[oldwood]

Imagine me having to teach a U.S.Marine to shoot a custom m/l rifle??????? All we had to do is to get him to adjust his technique a little , and wow , Told him I wanted my rifle back. Yea that happened.....Here's what he did ,one , off the bench,the Lehigh Valley stock style was smacking him in the cheek. Fix..Use the correct height bench support. Don't crawl up on the stock to sight the gun , lay the cheek on the gun stock. Most long rifles are made to shoot off hand , and w/the body against something to insure a steady aim. ....Two...Hold the rifle w/two hands in the normal sighting routine not w/a death grip , but snugly. You have to get the rifle through the 1/20th second it takes for the hammer to fall , sparks to hit the prime powder , and ignition. Once this pattern of firing each shot is mastered don't worry what the rifle is doing , concentrate on keeping the front sight on the target. Result....Consistent 50 cal. 2" groups @ 50 yds. Happy Marine........ Said he's ready for bear.

 

[TreeMan]

Were you cleaning between shots when you sighted the rifle in and then not wiping between shots on the return trips? Using dry “Dutch” patches like you mentioned requires cleaning between shots in my rifles or the shots start stringing high. Different daylight conditions can effect your shooting too with iron sights.

 

[Flintandsteel]

Something is different. I’d suspect patch/lube combo.

 

[Sparkitoff]

Were you cleaning between shots when you sighted the rifle in and then not wiping between shots on the return trips?

Actually, I don't remember. I don't think I was - I hardly ever do. But, since I can't remember I think that's a do-over with swabbing between to see if it makes a difference. I also cant remember if I put the fore-end on my hand or on the bag, so I will try both......

 

[hanshi]

If your rifle had a pinned barrel I'd blame unslotted barrel lugs. But I'll agree that it must be a variable in the technique when you fire. A flintlock absolutely does require major "follow-through". Keep your sight alignment after the shot and don't move until the rifle comes down from recoil. I use a tight combo and lube with mink oil or Hoppes BP Lube. So I don't need to wipe after each shot or dozens of shots since the bore always has only the fouling from one shot. Black powder doesn't deteriorate as long as it doesn't get wet. Pre-lubed bought patches can deteriorate.

 

[Carbon 6]

Shoot an off-hand group once and compare, does it still print high ?

 

[Rodd Boyer]

If the first session was shot on a cloudy day and the "high" group was shot on a sunny day (sun directly down on front sight), there's your answer. A bright front sight will make you shoot high.

 

[Pete G]

Another factor with light is a bright target. Old saying is "Light up, sight up".

 

[Dibbuk]

Has humidity changed? Humidity affects wood, and changes in humidity can change the pressure of the wood on the barrel, which would affect POI.

 

[mooman76]

Yes, actually the target could have something to do with it. 3" at 100y really isn't that much meaning that a very small thing could change it easy enough by 3". A larger target or where you are aiming at on the target. Center vs bottom. A larger target doesn't give as precise of a aiming point. A different color like mentioned can throw you off. I colored some targets for shooting and noticed the orange highlighter is more difficult for me to see in the early morning because the way the sun hits it.

 

[hanshi]

It didn't escape my notice that when I was shooting "benched" the rifle seemed to always group higher on the target. When shooting from a "field" position it invariably had a bit lower POI.

 

[Al B]

When shooting for groups, I've become accustomed to weigh the balls and segregate them into groups that were only a grain apart.
This has closed the group size and seemed to keep my zero

 

[Col. Batguano]

Some times odd things just happen. One day the groups are in the center of the bull, and the next day they're way off. Since I pull the barrel each time I clean, once I suspect this is happening I pull the barrel and re-seat it. It's only happened a couple of times, but each time it's happened, re-seating has returned it to the bull center. It hasn't happened since the first few half-dozen or so times I shot the gun, so my suspicion is that it was the barrel just shooting its' way in to the barrel channel.