.54 Caliber Accuracy

[Loyalist Dave]

Howdy folks,

My friend asked me to test fire his rifle with a .54 caliber, 42", octagon to round, Douglas barrel. He was having trouble with the accuracy, and wanted to see if I could find out what was wrong.

So at 25 yards, from a sandbagged rest position, I fired three shots of 3Fg Goex, using 50 grains of powder, and a .530 lead round ball made by Hornady, patched with .015 pillow ticking cut at the muzzle, and spit. Swab with damp patch between each shot. Loading was nice and snug, and akin to my other rifles.

Ignition was great, and the first three shots hit in a ragged hole just slightly right of the center line and about 3" high from the point of aim. So I adjusted the rear sight just a bit left, and shot #4 hit the center line, and equal in height to the first three.

Since one must use at least 60 grains of powder to legally hunt deer in my state, I upped the load to 60 grains, and the impact point moved up just a tad over shot #4...and I shot twice so I had a nice pair of holes from shots #5 and #6 touching, just slightly above shot #4.

OK so no worries so far... time to try 50 yards, which is where my friend had complained he saw problems.

So 60 grains of GOEX 3Fg at 50 yards, and the rest you know... WOW... the shots went to about 11 O'Clock from the bull and the group opened to 3". :shocked2:

So I went out and collected 5 patches, and they were intact, nice round black ring, but when I held them up to the sun, I saw tiny light areas ...tiny holes..., obviously from their being symetric spaced, they were from the rifling. In two of the five patches, it looked like only a quarter of the full circle had the tiny holes...wierd.

Is this enough "patch cutting" to explain the accuracy change from 25 to 50 yards?

In the past when I've had patches cut by the rifling, they were larger holes and very obvious, and also burned from the firing, but in this case the holes weren't burned as far as I could see, and weren't obvious except when exposed to a bright light passing through the cloth material.

So is it patch cutting or is there something else I might look for?

LD

 

[wayne terry]

First try a thicker patch maybe .018 and maybe try some FFg good luck be safe.

ST

 

[MSW]

sounds like you might want to go to FFg, and maybe a thicker patch ... if you're still having burn issues, you might want to try a wad of some sort between the powder and the PRB.

free advice, and well worth the price!

make good smoke!

 

[Rifleman1776]

How old is the rifle? That 60 grains should be just about spot on with a Douglas barrel. It may just need more shooting. But do try different patch and lube combos.

 

[Loyalist Dave]

OK thanks so far folks... Yeah it's not really burn-through, which is the wierd part, just the holes... I wonder if there is a tiny portion near the muzzle that is partially cutting the patches, THEN when fired and the patch passes back over that part (maybe the crown at the muzzle???) it completes the cut but the gases aren't hot enough at that point to cause a burn???

ZOIKERS :idunno:

LD

 

[Herb]

That is not enough patch holing to make any difference. Try 80 grains of either Goex 3F or 2F.

 

[BrownBear]

Since he's looking for a hunting load, I'd try a different lube while you're at it. I've not messed with a Douglas barrel, but in others I've had trouble with patches and larger charges when using spit. Speculation, but as long as you're messing around I'd try a "hunting" lube versus a "target" lube. TOW's Mink Oil Tallow is high on my list for that, but there about a zillion others.

 

[Ken Cormier]

IMHO changing to 2ff might help. Most agree that over 50caliber to use 2ff I don't. In my 62 smoothbore I use 3fff to including for a primer.
Douglas barrels are usally a great barrel. So unless it got by quality control then my best guess is to start all over again. As a barrel really messed up to be bad
And I mean start all over center the sights just like you are sighting in a new gun. That is the only way I can think to find out what's going on. :2

 

[Snakebite]

My Hawken rifle has a 34" Douglas XX barrel. At 50yds I use a .535 RB, 2F, pillow ticking from Wal Mart and mink oil lube. I get very good groups. Might want to try the .535 ball. I've tried .530 balls, but didn't get as good accuracy.

 

[biliff]

Just sounds like you need to do some more load development.

 

[Col. Batguano]

I've got a couple of flinters with Douglas barrels (13/16", 42" 40, and a 13/16", 44" 45) I can't make work consistently with spit patches either. Some days they're great. Others they aren't.

 

[hanshi]

Odd situation indeed. While swabbing the barrel with ScotchBright patches might help with any sharpness on the lands, I think some of the other posters are on the right track. I use 3F in all calibers with as thick a patch as will seat with reasonable pressure. So a thicker patch would be the first thing I'd go to and also try something other than spit lube. Switching to 2F might help although I've never noticed any significant advantage with it.

Right off hand I have trouble seeing the patch (minor) damage as the culprit. I've gotten excellent accuracy in the past even using patches that tore and/or burned through. As a guess I'd just call the barrel "finicky" and work on up with the higher charges until accuracy is restored. Maybe that along with a slightly thicker patch will bring better results.

 

[nchawkeye]

Just sounds like you need to do some more load development.

Agreed, one powder charge doesn't tell you much..

You can change the charge, ticking, lube, try an over the powder wad, etc....

 

[Loyalist Dave]

I agree one powder change normally doesn't tell you much, but it was a rather dramatic movement for impact...even allowing for the range change, the groups more than doubled in size, AND moved left 2". So instead of playing with more variables as I obviously was doing something wrong, I tossed out the dilemma to see if anybody else had encountered this before. Just to save time and avoid reinvention-of-the-wheel.

Thanks Herb for the confirmation that the tiny holes may not actually be a clue as they probably aren't causing a problem.

Brownbear's idea about using a lube instead of spit might also be a good idea... I don't, and my buddy also doesn't, do "target loads" so he's right we are working on hunting loads. We shoot our hunting loads even when target shooting as we use target shooting as hunting practise. So I might as well try my lube, and what the heck, might even try some commercially pre-lubed patches. I also might do some 2Fg.

A thick grease as a lube might eliminate the miniscule patch cutting problem too.



LD

 

[don hepler]

My Douglas barrel has very deep rifling, as compared to some of my other rifles. I use lapping compound on new barrels. Being a machinist for 40 years, I know any machining will leave varying degrees of finish and will vary from one cutting to the next. You can shoot it in, or lap it in. You can bet, that the Douglas barrel, will shoot good, with the right combination, and possibly some bore conditioning, if it comes from just shooting, or lapping. I like the thick drill material from Wally World.

 

[Herb]

A good thick patch material is cotton duck canvas, red, Wal Mart's UPC number 084132217185 at $5.97 per yard. I checked on it yesterday because I just used it in my .58 flintlock, working up loads for my mule deer hunt. The ratchet reading on my mike is .019 but it crushes to .013, and that is the important thickness. It held together with 120 grains of Goex 2F but is too thick for easy loading with .570 balls. I like the red color because the fired patches are easier to find. You can get a small strip to try, even a 2" strip. I like it as a heavy patch.

 

[Loyalist Dave]

Thanks Herb and Hadden West... I will get some thick cotton duck, and will look at maybe lapping the barrel. :grin:

LD

 

[flaming canvas]

If you are developing a hunting load, you wouldn't want to use spit patch. Mink oil works pretty well if you are going to have the gun loaded all day.

I would bump the powder up to 80 grains also.

 

[jethro224]

While I agree that you need to do more load development with patches, lube, and charge, one other thought immediately comes to mind.

the groups more than doubled in size, AND moved left 2"

What was the wind doing?

It doesn't take much wind to move a group 2". Just a light wind could do that.
A gusty wind can really open up a group too.
Wind does strange things. Even when it is steady or calm at the bench it can be gusty or just different downrange.

 

[kingsax26]

Random question, do you normally hunt with 60 grain charges? I used a 60 grain charge last year in my .54 and the ball stopped dead on the shoulder. Was not a killing shot and I had to shoot it again...... Was the most embartading hunting moment in my life.