R5M .25 standard-- Pellet spiraling problem

[J_J_Hussey]

As the topic title mentioned, R5M.25 use 25.39Gr JSB pellet, 860fpe, having pellet spiraling problem, it affected accuracy a lot, checked pellet skirt, the skirt not damaged, cleaned barrel, the problem is still there, anyone any idea or had the same issue with me?

 

[DanielL]

What's the crown look like?

 

[J_J_Hussey]

What is the CROWN? you mean head of the pellet or what?

 

[Kaeokini]

Aloha, 

take a picture of the crown, you’ll have to remove the shroud and it’s the end of the barrel.

Aloha, 

Keone

 

[J_J_Hussey]

The attached link is the footage of spiraling, 60 yards

https://www.dropbox.com/s/q82nhvohfehpafw/footage.mp4?dl=0

 

[J_J_Hussey]

Aloha, 

take a picture of the crown, you’ll have to remove the shroud and it’s the end of the barrel.

Aloha, 

Keone

Aloha, 

take a picture of the crown, you’ll have to remove the shroud and it’s the end of the barrel.

Aloha, 

Keone

hi Keone, which side of the barrel end? you mean the nut side of shround? i mean where the pellets out?

 

[JamesD.]

@ JJ,

The crown is the very end of the barrels transition spot. The muzzle. The last thing that the pellets touch when they leave the barrel. It needs to be at correct angle, smooth, no burr or lead build up.
Instead of the 25.39 long ones get the 25.43 Kings and try at exact same setting. I personally don’t think the ones you’re having problems with work as well as Kings. You could just have a lead build up.

 

[J_J_Hussey]

Just checked the alignment of the barrel, it's perfect as what i aligned last week, no change, there is no burr what we called crown, and very smooth...

maybe a deep clean of barrel?

 

[DanielL]

The attached link is the footage of spiraling, 60 yards

https://www.dropbox.com/s/q82nhvohfehpafw/footage.mp4?dl=0

Interesting. That is not the typical corkscrewing people have issues with that grows bigger and bigger with each loop. Yours seems to stay the same diameter or maybe even get better downrange. What distance was that at? Can you take a shot against a white target at a further distance and post that? 

 

[DanielL]

Just checked the alignment of the barrel, it's perfect as what i aligned last week, no change, there is no burr what we called crown, and very smooth...

maybe a deep clean of barrel?

Can't see the ends of the rifling of the barrel in that photo. Can you remove the silencer? 

 

[J_J_Hussey]

Just checked the alignment of the barrel, it's perfect as what i aligned last week, no change, there is no burr what we called crown, and very smooth...

maybe a deep clean of barrel?

Can't see the ends of the rifling of the barrel in that photo. Can you remove the silencer?

i checked the rifling by removed the barrel off last week, it's clean and no damage...

 

[BH]

Did the spiraling occur before and or after you “removed the barrel off last week”

just trying to help narrow it down to cause...

 

[J_J_Hussey]

Thanks BH, it's there before I removed the barrel, to be honest, I am not sure when it began, I found it from the GoPro footage, and then found the problem some periods videos.

 

[Feinwerk]

I think this is a very rare problem for EDguns. I've been reading messages for a couple of years and never seen one about spiraling. I have an R5M myself. Wondering if something could be going wrong with the bolt probe and magazine alignment causing the pellets to be jammed in at an angle?

if you bought this used, perhaps look at the o-rings on the magazines to see if they are too large and causing the pellets to tilt as they pass through from the friction going over the rubber. Just a thought.

Have you tried removing the bolt block and pushing a pellet through the barrel manually with a cleaning rod? You can feel the pellet enter the breech and see if a burr on any of the transfer ports is catching it. You can also feel it as it slips through the rest of the barrel and the constriction at the choke at the muzzle. Then you can examine the pellet after it comes out to see if it has been struck evenly by the rifling.



Good luck

 

[davidsng]

Do you have any shavings? (Tiny Piece of lead in the Breach after shooting.) Try hand loading and see if the spiraling stops. Then take off the shroud and baffles and shoot groups. If groups are better with single loading, have a feeding issue. If groups are better without the shroud, you have clipping. You either have to re-align the baffel system or shroud, or Drill bigger holes into the baffle system.

 

[J_J_Hussey]

To David and feinwerk, all are very good ideas, I will try one by one.

 

[Feinwerk]

Yes, forgot to mention checking the baffle inside your shroud for any foreign debris or whiskers of plastic, fibers from cleaning patches/boresnakes sticking out into the pellet path. This can happen if you ever shoot felt cleaning pellets with shroud in place. Check the end cap very carefully for signs of clipping at the exit hole.

I think spiralling can be caused by vibration and barrel harmonics also but I have not personally experienced this, just going from things I have read. You mentioned removing the barrel, did you get the torque right on the barrel tensioning nut?

 

[J_J_Hussey]

1, checked mag and probe alignment , it's normal;

2, checked o-ring of mag, tested pushing pellets out with pencil, it's fine!

Have to test grouping without shroud and stack in field for another day.

 

[J_J_Hussey]

Yes, forgot to mention checking the baffle inside your shroud for any foreign debris or whiskers of plastic, fibers from cleaning patches/boresnakes sticking out into the pellet path. This can happen if you ever shoot felt cleaning pellets with shroud in place. Check the end cap very carefully for signs of clipping at the exit hole.

I think spiralling can be caused by vibration and barrel harmonics also but I have not personally experienced this, just going from things I have read. You mentioned removing the barrel, did you get the torque right on the barrel tensioning nut?

Thanks feinwerk, the torque is 12lbf, it should be right, the mostly reason I doubt is the movement of plastic stack, I will align it careful ly and then check grouping.

 

[JWilson]

I would clean the barrel again to be sure.

If problem continues I would increase velocity by 5 fps and decrease velocity by 5 fps to see if there is change with velocity. 

860 is a very good speed for the 25.4s. Are you confident in the chronograph results? 

Is it every shot or occasional?