Load Development, Fouling and Vertical Stringing

[TJBCS]

I'm familiar with the causes of vertical stringing in general but I'm unsure when it comes to BP load development and fouling control. I was wondering if the experienced BP folks know specific things with these factors that can cause vertical stringing. I was shooting my TD with 68gr of Swiss 1.5 with a .060 wad using 512gr 20-1 cast boolit. It not only shot way higher than the sight setting (I had to to set to around 175yds for 200yd target) but the shots were are center but extreme vertical spread of 12+ inches. I believe the wad adds to the higher POI. I was just using a blowtube of 1 long breath between shots.

Last thing, the bullets are only .459 and much smaller than my groove dia but it seems they were properly obturating since they were center and stable. I would think if them being undersized was the major problem it would not be vertical stringing but more of a trainwreck pattern. Any ideas? Thanks.

[Don McDowell]

Vertical stringing can come from either being fouled out, leading, or inconsistent placement of the rifle in the rest and on the shoulder. Heavy trigger pull can cause problems as well.
Keep in mind those sights are regulated for a 1.1 inch bullet at 1300 fps. Or a 500 gr round nose at 1200.

[BLAHUT]

You did not say how you were measuring your powder ?? Using a cartridge gun, cartridge dirty in side brass. Might try weighing a few of you powder loads ? See if there is a difference between them, for a start ? Usually vertical stringing is caused by, variance in load, Amount of powder, fouled barrel, different primer power, difference in compression of load, bullet fit, bullet weight, wind in your face or behind you, how rifle is held, how / if, sight picture is consent, change in humidity, shooting over water, change in light, shooting off sticks or bags, stable bench, sitting, prone, standing, shooting off sticks - barrel placement on sticks or rest ?

[TJBCS]

Thanks Don and Blahut. Rifle is placement is good but I can always pay more attention to shoulder contact. I weighed all my powders for consistency and cleaned brass properly. And as I said, I'm knowledgeable about the common causes of vertical stringing. Bullet fit is definitely not ideal but my experience is that bullets tend to drift or you create a trainwreck grouping rather than vertical.

I am using magnum primers, so maybe time to try my WLR primers. I know primers are a factor in precision shooting but do you think magnum vs standard primers cause that much deviation?

Understood Don on the 500gr ~1200fps. That is what I am trying to dial in. I did not chrony this time out but i think 68gr plus wad had them moving a little too fast.

[Don McDowell]

For the most part I’ve found magnum primers to be detrimental with black powder
Some of the fake stuff they do help
When you get into the gun and you have to raise or lower the sight picture you need to adjust the front test so that movement is minimalized

[TJBCS]

Understood Don, thanks again. Definitely have several variations I need to try.

[Don McDowell]

Well good luck getting it figured out. The trigger pull on those rifles have never been known for accuracy, unless they've been given a good working on.

[TJBCS]

Thanks and yes the trigger is not great and I can see having vertical stringing issues with it. I'm not sure why I'm so committed to getting a 133 yo rifle to work decently but I guess it is the venture of problem solving and faith. I have made a lot of progress. I could not hit anything past 100yds a few months ago and the shots were all over the place IF they hit the target. Now everything is hitting the target and centered. Very interesting to see lots of big bullet holes lined up top to bottom 12+ inches.

[Don McDowell]

Those old rifles are fun to work with but can be frustrating as well

[Larry Gibson]

TDs are infamous for the first couple shots out of a clean barrel to shoot high like that. However, if the vertical stringing persists after a couple shots then there are other problems.

[Gunlaker]

Fouling control can have a big effect on vertical stringing. Here is an example. My silhouette rifle is a Shiloh in .40-65. A while back I was experimenting with BACO bore wipers and comparing with my standard fouling management of 2 wet patches per shot.

At 200m the first shot from a cold bore is usually around a minute high and to the left. The remaining shots group very tightly. When I use the bore wipers it's a completely different story. Each shot will go progressively higher on the target until the fouling between shots becomes constant. It takes maybe 5 shots to settle in, basically drawing a vertical line up the target. After 5 or 6 shots the rifle starts to group several minutes higher on the target than normal. If I switch back to my regular wiping routine then the shots go back to center.

The effect gets more pronounced the further you shoot. I've spent a ton of time on fouling control, especially with a chronograph, and I can say that fouling control and how good you are at it, is at least as important as load development.

Chris.

[Don McDowell]

Chris if you have that sort of problem with the BACO wipers, then you've got a problem with either what ever you're using to soak them with or the follower patch. I've also found with the 40-65 and 40-70 ss, one button on the wiper is plenty.

[Lead pot]

Vertical stringing can be a head scratcher for all of us that shoot these BPCR. I have done a lot to satisfy my curiosity why I have a wanderer on a clean string show up. I always blamed that little Gremlin I call Henry playing games with me down range.
I used bullets that were cold poured wrinkled just to see how much they wander out of a group as well as hard or soft alloys have effects and wad stack changes.
I shoot trapdoors and one has a larger bore/groove at .461" groove and it shoots a .458" diameter very well at 1/20 T/L and even with 1/16. Shooting black powder when the charge goes off with black powder the undersized bullet will be groove diameter even if it's undersized with a reasonable alloy hardness.
Where the trouble starts with groups opening up is a bullet to hard with an improper wad stack sealing the gas behind the bullet causing gas cuts or to soft pushing them to hard causing stripping and this smears lead in the bore. When lead starts building up things get wild. Lead build up is a larger issue than powder fouling.
I shoot often just for fun range time at bowling pins with out using fouling control except for an occasional blow up the breach when loading starts to get tight and as long as the temperature is not to high.
Here is a 200 yard target I shot 100 rounds through while I was reforming .45-2.6 cases for my new 25# .44-2.6. The brass was just sized down from .45 to .44 and final forming. I just loaded and shot without fouling control except for just a blow up the breach. No blow tube or wiping and that hole you see just 4 or 5 wandered outside of 4". It was a cold sunny January and that is tough on the fingers wiping between shots I call that a 200 yard ragged group.
A big issue for vertical stringing is what a lot of us wont admit, and that is the anticipation of the coming recoil. It might be an unconscious thing but I have caught this my self letting a shot off when I forgot to pull the hammer back and just heard the loud click
I think this is the largest cause of the stringing issue and improper controlling the rifle.

[Gunlaker]

Chris if you have that sort of problem with the BACO wipers, then you've got a problem with either what ever you're using to soak them with or the follower patch. I've also found with the 40-65 and 40-70 ss, one button on the wiper is plenty.

The problem with my 40 cal wipers is that they are all too small and don't seal the grooves so do a bad job keeping the bore clean. My first batch was a very early one and I'd heard a rumor that there were consistency problems with the early ones. I ordered a new st last year and they are the same. My 45 cal ones are pretty close to perfect.

I didn't post to complain about my wipers though, just to show the guy who started the thread that bore condition can definitely cause vertical stringing.

Interestingly, the first time I cleaned the turkeys with this rifle was using those very same early BACO wipers.

Chris.

[Don McDowell]

When you see this stuff about wipers giving problems the best thing to do is start looking at serious match score put up by folks like Ferringer , Johnson, Venhouse, Gullo ,Taylor and others and say hmmmm

[Gunlaker]

You missed the whole point Don.

Chris.

[indian joe]

Thanks Don and Blahut. Rifle is placement is good but I can always pay more attention to shoulder contact. I weighed all my powders for consistency and cleaned brass properly. And as I said, I'm knowledgeable about the common causes of vertical stringing. Bullet fit is definitely not ideal but my experience is that bullets tend to drift or you create a trainwreck grouping rather than vertical.

I am using magnum primers, so maybe time to try my WLR primers. I know primers are a factor in precision shooting but do you think magnum vs standard primers cause that much deviation?

Understood Don on the 500gr ~1200fps. That is what I am trying to dial in. I did not chrony this time out but i think 68gr plus wad had them moving a little too fast.

first question - if you are using your chrony some - do you get consistent velocity - if no that needs sorting first - if yes then that points to operator- (hold - hows it sitting on the rest etc)
FWIW --my shooting usually/always shows vertical with any kind of blade front sight - goes away when I put a round (peephole) up front ----this is called birthday sydrome I think

[Don McDowell]

No Chris I didn't.

[Lead pot]

Inconsistent moisture from whispers or patches will raise the velocity and lower it especially if the moisture is a cutting oil. I tried the bore pigs and found this going on both on paper and the chronograph. If the squeegee dont get consistent results there is going to be a difference down range.
Controlling fouling with bored pigs or patches both work. It's just going to be what ever works best for the guy using the method.
For me I will stay with just cotton and water. I get along with that just fine.
As far as watching the match winners what they do, well I do just that to rate my performance. When I see me close behind them I feel like doing hand stands. I seen Dave under my name at the finish as well seeing him above mine with tie breakers. I regard him and Doc Lay as well as Zack and a few others very hard holders. Brent Danielson is another to pay attention to. It's a shame that he quit posting.

[dave roelle]

Is your rifle bouncing off the sticks ?