DonnyFl Clipping issues

[woogie_man]

Hey guys,


Say I have been shooting my ghost more lately trying to get a slug worked up. Before when I had my 30 barrel I was using a DonnyFl Yokozuna and was having really bad clipping issues with both pellets and slugs. I thought I had a massive issue with the barrel not shooting, but when the Yoko was removed everything was fine. Well now that I have my 22 barrel I wanted went to test pellets and slugs today. Well I was able to get some basic tests done and accuracy looked decent with a few pellets and a few of my slugs. But when I put on either the Ryu or the Yokozuna I was watching the projectiles spiral like crazy. Removed the units and the accuracy was right back to where it should be.

I am wondering if anyone else is having issues with the quick removal mount on these units? I have a few other units to try out but with this ghost I am not having any luck with the Donny units on this rifle.

The original barrel had the full shroud and not in the 22 I have the tension barrel kit.


So what are you guys experiencing with these units?

 

[ChickenDumpling]

Not familiar with the ghost. But I have been watching some DonnyFL videos and actually considering those same devices. Could this be the difference from a shroud based connection compared to directly threading to the barrel? From my readings, and watching, the shroud based connection has more issues with alignment.

 

[6gun]

Hey guys,


Say I have been shooting my ghost more lately trying to get a slug worked up. Before when I had my 30 barrel I was using a DonnyFl Yokozuna and was having really bad clipping issues with both pellets and slugs. I thought I had a massive issue with the barrel not shooting, but when the Yoko was removed everything was fine. Well now that I have my 22 barrel I wanted went to test pellets and slugs today. Well I was able to get some basic tests done and accuracy looked decent with a few pellets and a few of my slugs. But when I put on either the Ryu or the Yokozuna I was watching the projectiles spiral like crazy. Removed the units and the accuracy was right back to where it should be.

I am wondering if anyone else is having issues with the quick removal mount on these units? I have a few other units to try out but with this ghost I am not having any luck with the Donny units on this rifle.

The original barrel had the full shroud and not in the 22 I have the tension barrel kit.


So what are you guys experiencing with these units?

It's not the donny itself if i had to bet. Zero clipping on my stuff even when I run 25 in my 22 mods. The qd works great too. Make sure there's no debris in the qd area to misalign the moderator. Iirc the bore on the 22/25 donny is .3125 or close enough to it. I just copied their bore on an experiment I was working on and no clipping with my home brew stuff. Do as you see fit, but I put a light at the open chamber and eyeball thru the mod and down the bore to see how lined up everything is.

 

[6gun]

Not familiar with the ghost. But I have been watching some DonnyFL videos and actually considering those same devices. Could this be the difference from a shroud based connection compared to directly threading to the barrel? From my readings, and watching, the shroud based connection has more issues with alignment.

Fwiw im on fx guns but im running shroud to qd adapter to ronin on my impact very successfully.

 

[woogie_man]

I have used both of these units on many different rifles with no issues. I am only getting the clipping with the ghost.

The original 30 cal was used with the shroud and the air stripper. So there was a chance for some misalignment. Though now with the tension kid on the threads are basically on the barrel itself. I suppose I could remove everything and just go right off the barrel, but it would be nice to not have to worry about that. I am going to try other units of course, but wanted to see if others were seeing the same thing.

 

[woogie_man]

It's not the donny itself if i had to bet. Zero clipping on my stuff even when I run 25 in my 22 mods. The qd works great too. Make sure there's no debris in the qd area to misalign the moderator. Iirc the bore on the 22/25 donny is .3125 or close enough to it. I just copied their bore on an experiment I was working on and no clipping with my home brew stuff. Do as you see fit, but I put a light at the open chamber and eyeball thru the mod and down the bore to see how lined up everything is.

I do have other adapters and I did try those as well to see if it was the mounting point that was bad. But I am still seeing the clipping issue.

 

[Gerry52]

If you're screwing onto a 12/20x1/2 adapter try putting a small o-ring around base of threads before screwing on mod. It just might help align things. Don't overtighten.

 

[woogie_man]

I will give that a try and see what happens

 

[mercado]

The newer YOKOZUNA and Ryu have pretty tight bores.. and they are heavy.. I found them awesome for my use because they go treaded directly in to the barrel. So i have little chance of clipping . But to be used in a shroud if there's is something with a little wiggle or more play that it should have.. you are really Goin to have problems, in the case of these tight bore moderators the advice is to be a size over .. these moderators where not designed to make guns silent..the are made to handle high power air guns and make possible to use them without hearing protection..

 

[jwrabbit123]

I have used most of donny s moderators only had trouble with 1 on a bt65 , it was a gun which had a barrel and a tube , so issue was it was not square to barrel so it was a 25 cal and i ordered a 25 moderator , I messaged donny and he sent me a 30 cal one which did not clip and suggested in future always buy next size up , so I also agree with this especially when you not screwing directly to a barrel but a tube as some guns may not be centered to barrel center , but this was like 5 years ago , since then ost of my guns I screwed directly to the barrels if I can which eliminates this ,

 

[woogie_man]

Yeah the cans I am using are a caliber up, using a 30 cal can on a 22. Not sure if the adapter for the quick release or what.

 

[greenbeans]

Had the same issue with one yoko. Tried changing one variable after the other, eventually eliminated the QD and all is well.

 

[greenbeans]

Here’s the thread from back then:

DonnyFL Quick Disconnect (QD)

So I got a second Yokozuna recently and it came with the QD, which I thought to be a nice thing… but then I started shooting. The gun basically turned into a shotgun. Checked the mod for clipping, nothing there (I upsized as well). Got my head scratching so I swapped it with the regular screw-on...

www.airgunnation.com

 

[OC_]

In my experience, mounting a moderator to the shroud always creates opportunity for baffle strikes. With the way how the actual barrel is so much shorter than the shroud and how the shroud may not be totally concentric with the barrel, you can see how this is not an optimal setup for a moderator.

Take off the shroud and roll it on a flat surface. If the shroud has a bow in it, its going to cause issues with a moderator.
If the shroud is true, try mounting the moderator to it and rolling it with the moderator hanging off the edge of the table if you can. Even if the shroud itself is true, the threads/adapter on the end might not be square of the rest of the shroud. If you can, put the moderator adapter on both ends of the shroud and test the other side. Even if one side is off, it will cause a problem.

 

[slugdug]

It's not the donny itself if i had to bet. Zero clipping on my stuff even when I run 25 in my 22 mods. The qd works great too. Make sure there's no debris in the qd area to misalign the moderator. Iirc the bore on the 22/25 donny is .3125 or close enough to it. I just copied their bore on an experiment I was working on and no clipping with my home brew stuff. Do as you see fit, but I put a light at the open chamber and eyeball thru the mod and down the bore to see how lined up everything is.

Ahh, so there is some built in gap, I wondered about that. Is the .3125 the same then on both .22 and .25 mods?

 

[woogie_man]

I have the tension kit on my ghost, so the gap between the barrel end and the threads for the quick detach unit is just a tension nut. So either the barrel from BRK isn't drilled concentric..... the tension nut isn't milled correctly, or the Donny quick detach is made wrong.

I have moved over to using a Sumo and a Hugget, and I have zero issues with either of those. So I am thinking it is something with the Donny unit. Its not a big deal as I have more than a few different cans to use, as well as I am making some as well to test out. So no big worries anymore.

 

[6gun]

Ahh, so there is some built in gap, I wondered about that. Is the .3125 the same then on both .22 and .25 mods?

It used to be, with the yoko things are different apparently. I will mic my yoko when it arrives. My donny fx and my donny ronin are both 5/16 inch bore approx. I was making my own from pvc with aluminum back caps and delrin front caps for a couple weeks and had some clipping issues there, mostly on my marauder. I opened up everything from 1/4 to 5/16 and it changed massively for the better.

 

[WobblyHand]

It seems that a lot of people think things are made perfectly, be they barrels, shrouds, airguns, or moderators. Sadly, they aren't. Some could be, but manufacturers take shortcuts to reduce cost. It is an exceptional barrel that is perfectly centered on both ends. Why? Because it's a tough machining problem to drill straight deep holes - and gun barrel bores ARE deep holes. Most gunsmiths indicate on the bore and then cut threads relative to the bore, not the outside diameter of the barrel, simply because the bores are not guaranteed to be centered.

If we are lucky, the bore is centered at the muzzle, the shrouds are trimmed on a lathe to ensure their straightness, all the pieces are machined true, and all the myriad adapters were likewise made on a lathe. (If you find such an airgun, you either built it yourself, or you paid some serious money for it.) Oh, and there's tolerances. We can't have lovely tight slip fits all the time on mass produced equipment, at least for the costs we all want to pay. Screws have to have clearance, or they're difficult to tighten or loosen.

If you want to ensure you won't have major issues on your latest moderator acquisition, it would be good to use a range rod, or it's equivalent, sticking out of your muzzle while you fit your moderator. If it hits or rubs, so will your projectile. Actually you need some clearance, because a very close flyby will be affected by the proximity of the baffle. Most, if not all moderator issues (besides a gross defect) are due to tolerance issues, or stacking tolerances between all the airgun parts and the moderator. With some care in assembly, many can be fixed simply, or slightly bored out. Other cases can be more problematic, where one has to hunt down the "crooked" part.

Due to the long length of barrels, it doesn't take much of an angular error to create a baffle strike. A part (or assembly) that is off by 1/4 a degree can cause a bit of heartache, and is very difficult to just look at and identify the problem. You need to measure it carefully to see if that's the problem - eyeballing usually isn't good enough. A 1/4 degree error over 12 inches is 0.052", which is an appreciable fraction of a 0.22 diameter (23.8%).

All of the above reasons, is why most manufacturers simply state to use the next size up, because they have no control of how well your airgun was manufactured. Sometimes even that is not enough, and you need to resort to a range rod, o-rings or more for alignment.