Seeking some guidance

[John Shields]

Well, I finally got to do some shooting. Just trying to find a load that will hit what I am aiming at.

This group was fired at 60 yards, and the funny thing about it, is that this is with three different charge weights, 85gr. 95gr. and 110gr.

I didn't have time to do more shooting, so now I am wondering, why would 3 different charge weights, by volume, land so close together?

 

[Ken Cormier]

First good shooting. You did not mention which shot was which. I suspect top to bottom of the target. As increasing the charge can raise the impact point. Can really tell with out more info. Let us know.

 

[Artificer]

I believe more info is needed.

What is the .....

Caliber?
Actual Bore Size?
Diameter of Ball?
Thickness and type of patch?
Rate of Twist in barrel?
Type of rifling?

Gus

 

[John Shields]

It is a .50 colrain barrel with RBR.

That is all I know about the barrel.

I am just finding it hard to believe that such a large change in powder charge would raise the impact so little at such a close range.

This is my first BP.

And this site is all the help I have with this.

Thanks

 

[Rusty_Nail]

When I saw your first post, I guessed maybe a 58 or 62 cal. rifle.

You are past any sweet load for a 50 cal. that I have or had. Most are in the 60-70 grain range.

With a 50 cal. maybe at the 95gr. and above, POI won't go up anymore, because there might be unburned powder blowing out the front?

For some reason, I remember a post on here showing velocity is not linear per grain, and has no return on powder investment above a certain grain weight.

Maybe Zonie posted it?

 

[Artificer]

That's possible.

I wonder if the patch and ball combination are loose enough that any increase in pressure just blows by the loose patch? This is part of the reason I asked what the measurements are for the bore, ball diameter and patch thickness and also what the patch is made of, though I think I forgot the latter up above.

John,

Have you ever picked up fired patches after your shoot? If so, what do they look like?

Gus

 

[coloradoclyde]

I am just finding it hard to believe that such a large change in powder charge would raise the impact so little at such a close range.

Not sure I understand your question but bullets travel in an arc, but it take a certain distance before it become noticable. there is just not enough of a powder charge difference or distance from the target to make it noticable.

 

[Rifleman1776]

I am just finding it hard to believe that such a large change in powder charge would raise the impact so little at such a close range.

Not sure I understand your question but bullets travel in an arc, but it take a certain distance before it become noticable. there is just not enough of a powder charge difference or distance from the target to make it noticable.

Tha it about what I was going to say. The difference will be more noticable at 75 or 100 yards. The ball is still on the rise at 50-60 yards. You need to focus more on grouping than poi for now.

 

[John Shields]

Thanks guys. I did recover that last two patches, and they were burned bad. I have read on here, that that is a bad thing. Next time I get out, I will go down to 75gr. and see what happens.

Again, thanks so much for all your help.

 

[bpd303]

Burned patches usually indicate poor patch fit. If you don't have thicker patch material, try a wad over the powder.

 

[MSW]

if you don't already have a copy, you should get Dutch Schoultz' method.

here's a link:
http://www.blackpowderrifleaccuracy.com/

make good smoke!

 

[coloradoclyde]

Burnt patches could also be the material itself, or your lube/technique, or a rough bore or my annoying posts they have been know to burn even the toughest of hides :grin:

 

[Johnny Tremain]

Im cheap, look up the Davenport formula, on the forum, and find you max charge, THEN work backwards until you find the most accurate.

Mine happens to be the max

 

[don hepler]

I have a 50 cal. Colerain swamped barrel, but have not tried many different combinations. I think some barrels, just seem to work, with whatever you feed them. My Colerain barrel will handle a .022 patch with a .490 barrel, and shoots a nice group at 50 yards. I forgot what the charge was. I shoot several rifles, and have to refer to my notes. However, I have never fired over 80 grains and your results are very interesting.

 

[Zonie]

The Davenport formula doesn't really give a MAX powder charge for a rifle.

It was developed by a target shooter so what it really gives is a value that is a recommended max for the best target shooting accuracy.

When paulvallandigham (RIP) first introduced the formula on the forum, many misunderstood it and thought it represented the MAX powder load for efficiently burning the powder.
That is, powder loads greater than the Davenport value were a waste of powder because a increase wouldn't add any velocity.

Of course, powder loads larger than the Davenport value do increase velocity and energy of the projectile.

I'm mentioning all of this to prevent another knock down/poke in eye debate that always seems to start when the Davenport formula is mentioned.

The formula, for those interested is the volume of the bore of the rifle times 11.5.

For a .50 caliber rifle with a 28 inch barrel that equals:

((.50/2)^2 X Pi) X 28) X 11.5 = ((.0625)X 3.1416) X 28) X 11.5 = ((0.1963) X 28) X 11.5 = 63.225 grains.

For one of pauls comments about this, follow this link:
http://www.muzzleloadingforum.com/.../hl/"Davenport+formula"/fromsearch/1/#1154107

 

[Major Tim]

110 gr.?! You're a braver man than I am! Those loads are more than I've shot in a .50

I've settled in at 65 gr. for target shooting.

 

[don hepler]

I agree with you on that. I would be afraid that a 110 grains would crack my stock, or my shoulder. If I wanted to shoot that big of a charge, I'd get a Hawken.

 

[mooman76]

Not really enough shots to make a proper evaluation. First shot or two are usually off anyway because of fouling.

 

[Grumpa]

Ditto on the Dutch Schoultz method.

Three shots fired with three different powder charges won't tell anyone anything. You have to fire groups of 5)without any variables (other than yourself). Then you change powder charge, or patch thickness, or whatever, (just one variable at a time/test), and fire another 5 shot group. Then you can compare the differences between the groups.
Then you go back and reprove your results.

 

[John Shields]

I wasn't shooting for group, I was trying to raise the POI to meet the POA. Now it looks like, I will have to file on the front sight. Not something I was wanting to do.