My groups opened up. Patch change?

[YJake]

Long story short, I was shooting well with my .54 Rice 44” radius rifled barrel using 100gr FFg, .530 ball, and a lubed mattress ticking patch.

I shot today with the same set up and instead of shooting the center out at 75 yards my group opened up to about 6”. I tried more/less powder and the problem persisted.

Fast forward to me cleaning the rifle tonight. I realized I had started using a different lubed cotton .020 patch instead of the original lubed mattress ticking. I took out my micrometer and the new patches measured .020, but the original mattress ticking measured .022

I never thought something so small would make such a difference, but is that possible? My shots were hitting lower on target and the group was opening up. Less of a seal may be causing less velocity and lower point of impact?

I was going to hunt with the rifle this weekend but now I’m nervous. I’ll be taking it to the range to shoot using the original mattress ticking tomorrow afternoon, hoping for good results.

-Jake

 

[TreeMan]

Yep a patch change can change your group that much. Other factors to consider is wind, and difference in the direction of the sun on your sights between the two trips to the range. I have a range at home that has perfectly measured distances to the target boards. My range is surrounded by trees and is always shady. Groups and sight holds I use at home are totally different when i shoot at the club range I belong to which is in an open sunny field. Once you find what works in your rifle stick with it. Small changes can make a big difference.

 

[Art Caputo]

Were you able to observe any difference in your spent patches(if they were checked). Is 75 yards your zero range? All things being equal, it would take an excessive loss in velocity(+300FPS) for the ball to drop an additional 6” at 75 yards. While some velocity may be lost, it may simply be a point of impact change due to the change in patch. I have seen as much as 1-2” POI shifts, and accuracy differences at 25-50yards between .018” ticking and .015” cotton patches with only minor or no difference in velocity. I agree with TreeMan, and I wouldn’t rule out day to day lighting differences on the sights, or other factors like wind, mirage, etc. These will magnify the effect on accuracy as range increases.
Just some thoughts....Will be very interested to hear about your re-test.

 

[YJake]

My zero range is 75 yards.

Yes, the lighting is darker due to the time change and I am currently only able to shoot in the afternoon, whereas I was shooting mid day a month ago in broad daylight.

The patches look similar to the old ones after shooting, but every few shots I’ll have a single slight tear in the new ones. Others look as though they can be reused.

Here’s a fired patch from when the rifle was shooting well.

-Jake

 

[Grenadier1758]

Yes, that slight difference in thickness can cause quite a change in ball, patch and lubrication performance.

The thickness changed from 0.022" to 0.020". I would also suspect that the density of the weave also changed. Look through the material toward a light. Can you see speckles of light? I would do a mild compression test to see if the new material compresses more than the old.

The occasional tears seem to indicate a weaker, less tightly woven patch material. Wash the new patch material in very hot water and dry in high heat to tighten up the weave.

 

[hanshi]

Understand that Rice radius groove barrels have grooves right at .016" deep while most square cut grooves run around .008" to .012". This means it takes a thicker patch to fill those deep grooves. Your barrel with a .54" bore + .016" + .016" (grooves) equals .572" that the patch must seal. The best way to determine compression in the grooves is to measure the material compressed. Some shooters use a micrometer, I rely on a caliper and squeeze the jaws down on the material with thumb & fingers to get a truer reading. Whatever the material always measure exactly the same way. I patch using canvas (.023" to .024") compressed; it measures about .030" without the extra force on the caliper jaws. In order to fill the grooves in your rifle, but with no groove compression, will require a patch .032" compressed.

 

[Rifleman1776]

Lot said so far. But the key is consistency, consistency. As they say in the south "dance with wat brung ye". Stick with what worked for you in the first place.

 

[YJake]

The old patches tightened things up and raised my point of impact to where I had it. I experimented with larger powder charges some too, but saw little difference in grouping.

@hanshi Your comments on Rice barrels make perfect sense in regard to what I have experienced. I’ll be ordering thicker patches soon for experimentation. I use a short starter to load my .530 ball/.022 patch combo but it starts easily and I run it home comfortably with the rifle’s hickory ramrod. I’ll be on the hunt for some thicker patches and begin measuring my patches compressed with my dial calipers.

Six shots from today at 80 yards. My chronograph tells me this load averages 1755fps with 100gr FFg.

The bullseye was a test shot with 110gr FFg (1800fps). Obviously a fluke.

-Jake

 

[MSW]

I agree with Rifleman 1776 ... you should go back to your original patch & lube combination.

 

[SDSmlf]

The radius bottom Rice barrels I have perform great with thicker patch material. The non compressed measurement doesn’t mean much, it is the compressed measurement that tells the story.

Currently using 10 oz canvas that I got from BurlapFabric. It is .022” non compressed, .0165” compressed, at least the way I measure it with a radius anvil mic.

You may also want to get Dutch’s muzzleloader accuracy system. He goes into a lot on this very topic. You can PM him here on the forum @Dr5x or go to his website for more info, Black powder rifle accuracy system -

 

[Dphar1950]

I zero all my hunting rifles to be about 1" high at 100. Thus can use the same hold from 0 to 120 yards for deer sized animals. But my loads are a little faster than 1755.

 

[oldwood]

other day at the range , all i did was change from grease lube to competition patch lube(supposed to be same consistency as spit). Patches looked as if they could be reused , but group size improved...oldwood

 

[Dphar1950]

other day at the range , all i did was change from grease lube to competition patch lube(supposed to be same consistency as spit). Patches looked as if they could be reused , but group size improved...oldwood

High friction lubes, like spit or Sperm Whale Oil (from the cavity in the head, not the oil rendered from fat) will often shoot better than slick lubes will. But they also tend to load harder. I never use a patch lube that contains water. I used well rendered tallow, Pure Neatsfoot Oil or a a mix of Neatsfoot Oil and Beeswax. But Beeswax must be very carefully heated, in a double boiler. OR for accuracy loads a mix of 1:5 or 1:7 water soluble oil:water soak the patches then allow all the water to evaporate. This gives best accuracy in my heavy rifle but requires wiping every shot. The dry teflon patches are supposed to shoot extremely well too. But these all require careful wiping. A heavily damp patch, not dripping wet, on a fairly loose jag so it rides over the fouling going down then bunches in front of the jag when its pulled back up to grab the fouling. This prevents or at least lessens the pushing of powder fouling to the breech face. Turn the patch over and repeat. Then a dry patch the same way. An overly wet patch will put too much water in the breech. This will give a uniform bore condition shot to shot. I put the wet patches in a tin or a tupperware container and put some water on them and let them soak it up over night then make sure they are not too wet, if they are add a few more patches to soak up the excess or squeeze it out. These dry patches are high friction and tend to give more consistent velocities than slick lubes. Though some rifles shoot slick lubes very well too. But when shooting a chunk or rest match I wipe every shot. As a friend says, "you don't have to wipe every shot, but you have to wipe every shot to win".

 

[Rifleman1776]

A heavily damp patch, not dripping wet, on a fairly loose jag so it rides over the fouling going down then bunches in front of the jag when its pulled back up to grab the fouling. This prevents or at least lessens the pushing of powder fouling to the breech face. Turn the patch over and repeat. Then a dry patch the same way. A

Great post. But I do have some issues with the above statement. My technique is to dampen with wiping patch (cotton baby blanket flannel) with my mouth. Then I wipe, turn over the patch and wipe again. BUT, I do not follow with a dry patch. Doing so risks the dry patch sticking in the bore. Don't worry about moisture in the bore hurting anything. Your barrel will be warm from the shooting and will get rid of excess moisture.

 

[Dphar1950]

Great post. But I do have some issues with the above statement. My technique is to dampen with wiping patch (cotton baby blanket flannel) with my mouth. Then I wipe, turn over the patch and wipe again. BUT, I do not follow with a dry patch. Doing so risks the dry patch sticking in the bore. Don't worry about moisture in the bore hurting anything. Your barrel will be warm from the shooting and will get rid of excess moisture.

The patch in the mouth works but the patches are more uniform in water content when they are all together. And uniformity is the key.
If you only use one dry patch its not truly dry since it picks up moisture from the bore and comes out damp. And in chunk/plank matches the barrel never gets hot or at least not very hot. Shoot a shot, other competitors shoot, then retrieve targets, post another, then shoot it, one shot per target. With initial sighters maybe 12-13 shots over the course of 2-3 hours or more. If you have a number of shooters there is a lot of dead time. Plus the 1 1/4" x 44" barrel of the rifle in my first post does not heat very fast. If I am shooting offhand, gong matches etc then the rate of fire is higher the barrel a lot lighter and I don't wipe since I use tallow or Neatsfoot oil etc for patch lube and use a blow tube.
This is a 19th c painting of a plank rest turkey match. Its better than laying in the snow and if you have shooters who have problems getting in and out of prone position.

 

[Dphar1950]

Note that the man to the right of the spotter has a tube or telescopic sight.

 

[Dphar1950]

My zero range is 75 yards.

Yes, the lighting is darker due to the time change and I am currently only able to shoot in the afternoon, whereas I was shooting mid day a month ago in broad daylight.

The patches look similar to the old ones after shooting, but every few shots I’ll have a single slight tear in the new ones. Others look as though they can be reused.

Here’s a fired patch from when the rifle was shooting well.
View attachment 50917

-Jake

Look the where the fabric is made. All the chinese "ticking" I have bought is junk. Will tear across the back of the ball during loading. If you need heavy patching see if you can find some heavy linen used for upholstery and/or drapes this may solve the problem. Linen is far tougher and has a higher ignition temp than cotton. If you find some that is just little too thin buy a small sample then try washing it hot and drying it on high. Denim is another option.