General Comment - Accuracy vs Caliber

[FishDFly]

The original discussion was:

I'm having a bit of a frazzle period. I've been *icking around with a 45 caliber flintlock (42" GM barrel) for a few weeks now, off and on, trying to develop a consistent load that generally goes were I point it. Been having a terrible time, and just when I think I'm getting close everything goes cafluey.

I also have a 36 caliber percussion (44" barrel maker unknown) built 30 yrs ago or so by Robert Ashe that seems to shoot quarter size groups at 50 yds no matter what I put through it. Problem is it has a 44" barrel and weighs 9.5 #'s. It's a bear to shoot off hand.

So what goes? PS: I know this is a rediculous question; but now I feel a lot better



With the intense discussion and indepth discussion of twist rates and mathematical forumulas, did anyone answer the original question or did I miss the answer?


RDE

 

[paulvallandigham]

Richard: The question changed to:

"OK, think I worded my question wrong. I'm not worried about the cafluey 45; I'm working and resolving that.

My question was more to why the 36 seems to be so inherently accurate and much more forgiving of what loads are in her. I was punching bulleyes with her off the bench, the very first time I tried shooting her. 40-50 grns, doesn't seem to matter much. Is there something inherently more consistent and accurate about the smaller calibers or did I just stumble on a very good rifle."

Short Start tried to suggest that the Rate of Twist probably explains why the .36 is so much more accurate. I then mentioned that One factor like the ROT may Not be the explanation because no one can really agree on what ROT works best in a given rifle and caliber.

So, yes, I think Short Start tried to answer the question. The rest of us just don't know. IF SPLAIS were to give us barrel measurements- groove diameter, land to land diameter, ball diameter used, patch thickness used, patch lube used, caps used, powder charge used- weighed or by volume,ROT, Length of barrel, width of barrel across the flats, powder used, granule size used, etc.- we might be able to deal with some of the other variables and come up with some ideas about why his .36 shoots so well. :shocked2: :thumbsup:

Without actually seeing the gun, and shooting it, there are way too many variables out there to consider, and any ideas are nothing more than a " hunch"- an educated hunch, but still just a hunch. :hatsoff:

 

[rawdog]

I agree with Paul, I thought it was answered more or less to the degree that enough info was available to enable an answer to it, and in the process some other questions came up.

I hope that is not a bad thing....?

YHS,
rawdog

 

[Splais]

Yes, and unfortunitely I have no way of knowing the twist, land/groove data or barrel maker.

I can tell you I am shooting a swagged 350 ball using 40 grs of fffg. The patch thickness doesn't seem to matter between .15-.18 pillow ticking. I am using DS's dry lube system, mixed at 5:1 (water/Ballistol; but then I've shot everything from 4:1 to 6:1 and .15 to .18 pillow ticking and got pretty much the same results. I don't know if it's my extraordinary marksmanship, the 44" barrel, or the moon and stars all lined up. :hmm:

 

[paulvallandigham]

AH-H! Now that is something we can teach you about.

To measure the ROT, use a thick or double oiled patch on your cleaning jag, and run it down the barrel. Now mark the ramrod at the muzzle. I use the front sight of the gun as my monument, and mark the top of the rod. Now, Very slowly pull the rod back out of the barrel, turning it to the right as you pull on it so that the patch stays in the grooves. You may have to do this several times to get the hang of it. Its not as easy as it sounds.

OR, you can use a bore brush, and one patch that is oiled down the barrel. The bristles will poke through the thin cleaning patch, and dig down into the grooves in the barrel. They will hold the rod to the grooves of the barrel even better than a tight oiled patch will.

Keeping an eye on the mark, watch the rod turn until the mark is now on the bottom of the barrel. Measure the length of the rod from the mark you made when the rod was all the way down the barrel, and the mark was on the 12 o'clock position, to where it now is at the 6 o'clock position. The length should represent 1/2 of the ROT.

If you get 17 inches, the ROT will be 1:34", for instance. If you got 24 inches, the ROT will be 1:48.

Sometimes the ROT in these guns is so slow that you have to stop pulling out the rod at 1/2 turn, and then multiply the length of the rod from the muzzle to your mark by a factor of 4 to get the ROT.

With an 8 sided barrel, and flats on both the top and bottom, as well as the sides, it fairly easy to stop pulling the rod when the mark is on one of the side or bottom flats.

As to bore diameter and groove depth, and groove diameter, all you need are inside calipers. If you have a set of calipers, they come with both inside and outside jaws, to measure both. You can buy a quality dial caliper from Midsouth for about $20.00. If you don't want to own such a tool, just stop by a local machine shop, and ask one of the men to measure the muzzle of your gun for you. The bore diameter is the distance from one land to the one opposite it. The grooves are the cuts in the bore to create the lands.

If you were to use a lead slug to " slug the bore"( you usually need to take the breechplug out to do that correctly)the measurements would be the opposite on the slug- that is, the high sides would be the grooves, and the grooves in the slug would be the lands of the rifle.

You can also measure the grooves to the nearest flat on the outside of the barrel, and then also measure the land to the nearest flat. The difference is your groove depth. Bore diameter( land to land) plus groove depth X 2 = Groove diameter.

Birddog probably knows what the bore diameter an groove depth is for the barrel he used on the gun, and he probably knows the ROT, too.

Best wishes to you on that gun. Paul :thumbsup:

 

[Dave K]

I find it easy to just take some tape, masking tape or what ever. Make kind of like a flag of the tape that is wrapped around the rod. Really easy to see and watch as you withdraw the rod.

 

[Dphar]

OK, think I worded my question wrong. I'm not worried about the cafluey 45; I'm working and resolving that.

My question was more to why the 36 seems to be so inherently accurate and much more forgiving of what loads are in her. I was punching bulleyes with her off the bench, the very first time I tried shooting her. 40-50 grns, doesn't seem to matter much. Is there something inherently more consistent and accurate about the smaller calibers or did I just stumble on a very good rifle.

You need to keep working with the 45, 45s may need 60-75 grains to shoot best.
Patch thickness, ball diameter, are you picking up the fired patches to see if they are coming out in one piece?
If not you may need a thicker patch or the crown may be cutting patches.

Its a new barrel it may need to be shot 50-100 rounds or have a tight wad of steel wool (OOOO) run up and down 20-30 strokes to break in in.

Dan

 

[Tom Compton]

OK, think I worded my question wrong. I'm not worried about the cafluey 45; I'm working and resolving that.

My question was more to why the 36 seems to be so inherently accurate and much more forgiving of what loads are in her. I was punching bulleyes with her off the bench, the very first time I tried shooting her. 40-50 grns, doesn't seem to matter much. Is there something inherently more consistent and accurate about the smaller calibers or did I just stumble on a very good rifle.

In your example one small bore and a limited number of larger bore rifles were used and I do not recall the distance. My experience is the opposite especially at longer ranges.

I think a .36 is plain easier to shoot - less recoil, muzzleblast, etc. In fact, when shooting at 100 yards or more, I believe that, as a group, larger calibers are more accurate than small bores. This will be hard to evaluate as there are so many differences in barrels and twists and I am sure there will be plenty of one of a kind examples brought to bear.

IE, in shooting modern pistols, .22s are easier to control because the recoil of larger calibers - .45ACP, .41 Mag, .44 Sp and Mag, etc - magnify the differences in recoil, trigger control, grip pressure, etc.

IE2, modern long distance shooting at 1,000 yards does not see many if any 5.56 entries and many even larger than 7.62.

IE3, I have not seen a large ML RB bench match at 100 yards or more won by anything smaller than .50 and usually it is .58. Could be that it has happened but as I said, I have not seen one.

Enjoy the .36 and keep working on the others.
TC