FX bad groups with slugliner and donnyfl ronin

[Powerage]

Hello. Today I got my slugliner for my 700 mm 25. Cal. Fx impact. With the pellet liner I have been pushing mk2 33.95 grain at 950 FPS with nice groups at 100 yards. I have some nsa on its way in the mail so I decided to change the liner and shoot some groups with the MK2 33,95 pellets. And to my surprise they where all over the place at 30 yards . I tried to remove my Donny FL ronin and it gave me nice groups . Tried to reassemble everything a couple of times but still the same problem . Any ideas ? 

 

[xindaris]

Have you checked the end of the moderator for pellet clipping?

 

[Powerage]

Thank you for the reply. I checked now and yes it’s clipping. Maybe is should index the liner ? 

 

[xindaris]

Take a close look at the liner at the muzzle and make sure when they bored and rifles it that the bore is not off center. If it is I would send it back for replacement. If the liner is threaded at the muzzle end they may have cut the threads off center. Would have to be replaced also.

 

[jps2486]

I would recommend a larger caliber moderator. I shoot a 30 cal Sumo on my 25. No worries about as accurate and quiet as the origninal FX moderator..

 

[Powerage]

I inspected the liner and it’s hard to tell if it’s something wrong in there. I will try shoot again tomorrow. With and without the Donny. Thank you for the reply

 

[Powerage]

I would recommend a larger caliber moderator. I shoot a 30 cal Sumo on my 25. No worries about as accurate and quiet as the origninal FX moderator..

Next time I’ll consider that. Thank you for the reply 

 

[Roachcreek]

You can drill out the Ronin with a drill bit slightly larger than the Ronins bore to give you more clearance.



Roachcreek

 

[xindaris]

If you have a caliper you can measure a side then compare it to the other side. Just make sure if the caliper is touching a land or a groove on one side you do the same on the other side. Also check both ends of the liner with a straight edge. When you put it across hold it down and you should see no light on either side.

 

[wimpanzee]

on my dreamline, the slug liner was slightly shorter than the original pellet liner, and this resulted in a different index position of the moderator when it was screwed on - the printing ends up on top, instead of on the side, about a 35-40 degree difference. i wonder if your moderator screws on a little bit further now, and causes a misalignment from a similar effect - I have heard of a few instances of the slug liners being a mm or two shorter.

 

[xindaris]

FX is a good company. I am sure if you get in touch with them they will make it right. Call FXUSA.

 

[slo642]

FX is a good company and I would bet they will help. I would think it best to check with FX as clipping should not occur ever. I don't think it is a pervasive problem for them but it has been mentioned here often enough that the source needs to be isolated. There is a finite number of things that can cause this issue if they haven't already found the culprit I bet they want too. AEAC just posted a video if you watch it you do get the feeling of how much they care about quality and that there defect rate is low. If liners are leaving the factory or getting damaged in shipping its reasonable they could work out a solution. If the source turns out to be after the liner arrives at the dealer then users and dealers have to be aware of proper handling as to prevent future issues. drilling out moderators is a mask for a symptom not a fix. No manufacture can address an issue if they don't have access to product with the issue.

the term liner is used here but it could stand for any portion of the system that caused the issue.

It should be noted that moderators need to be manufactured to high standards or they could cause this.

 

[Powerage]

I did some testing today. Opening the Ronin with a drill was easy. But it was still shooting unacceptable . Shots everywhere. Removed the barrelshroud and things got a lot better. Then I added the original fx moderator. Ugly looking gun, but I could stack pellet on pellet again. The shroud must be causing this but I don’t know how to fix it. 

 

[Powerage]

on my dreamline, the slug liner was slightly shorter than the original pellet liner, and this resulted in a different index position of the moderator when it was screwed on - the printing ends up on top, instead of on the side, about a 35-40 degree difference. i wonder if your moderator screws on a little bit further now, and causes a misalignment from a similar effect - I have heard of a few instances of the slug liners being a mm or two shorter.

I emailed donnyfl and he said the same. I will check my liners to see if this one shorter 

 

[xindaris]

See if there is any clipping where the moderator screws to the barrel.

 

[Powerage]

See if there is any clipping where the moderator screws to the barrel.

Its hard to tell but I can’t see any signs of clipping there. 

I also measured the liners . They are the same length. 


I get nice groups with the shroud alone or the moderator alone but not together. 


tomorrow I will try the pelletliner again with the shroud and the donnyfl just to confirm it’s accurate with that combination. 

 

[xindaris]

Take off the moderator and look through it to insure there is no obstruction in the bullet path.

 

[xindaris]

When you put your new barrel on did you put the barrel o rings in the same positions on the barrel?

 

[Powerage]

When you put your new barrel on did you put the barrel o rings in the same positions on the barrel?

The O-rings on the liner ? I will check that to. Thank you for the reply 

 

[xindaris]

Yes the liner.