Taming the bark of an Avenger

[swingin]

Pretty crude cut but you can see it hit the one baffle.  Plus the tip.

[subscriber]

Thanks, Don

That tells me what I need to know. 

[subscriber]

Don,

I have passed on a design with 50% thicker walls to Bob for printing.  I will follow up with one that effectively tapers the wall thickness, to take some weight out of it where it does not need it.

Before we get too carried away, could you measure your Avenger's barrel diameter, or gauge it.  I have opened up the barrel channel in the insert design by 0.2 mm.  That should ease barrel insertion, providing the .25 barrel has the same OD as the .22 barrel.  Now, it is hardly likely that you got the insert into the barrel socket, without breaking it; if the .25 barrel OD is much larger than the .22.

Speaking of your Avenger; are you using the stock front internal barrel to shroud support, in the standard location?  Is your shroud modified from stock in any way?  If so, please describe.    If the stock barrel to shroud support is moved rearward, or removed, then that may change the barrel to shroud alignment, if only my insert is centering the barrel and shroud at the front end. 

My modified design adds a little material to the insert OD where it lives inside the shroud to help center the shroud to the barrel, just in case.

[swingin]

I don't have a way to measure the barrel without removing the strip stack pack and the whole shroud with 3 barrel bands, plus the Haji centering device. I can but it's a pain.

I am using the stock centering device where it was when I got it. The shroud has three holes drilled in the rear portion for the stack pack with melamine around the end of the barrel. Check Haji's video install for details.

I also have the BR kit, all three parts but that's just cosmetic. So when I put it all back together it's still a tack driver, it just looks cooler and feels much better too.

Let me know if you need me to tear it down again. Thanks for your support! 

[subscriber]

Thanks, Don

I found a Hajimoto strip stack pack install video for the Origin.   The Origin is almost the same as the Avenger, except the latter has a regulator.

This link should start the video at the strip stack installation: 

What I don't understand is if you have the Hajimoto air stripper on the end of the barrel, how did you install the Plume LDC?  That has a barrel seat and twin reflex air strippers.  If you are not using my air strippers, air entering them from behind will travel forwards into the pellet path and buffet the pellet.  This will teds to make the pellet wobble.  So, that might be a contributing factor for why you got clipping.  Ditto for if you have the Hajimoto baffles ahead of my insert design.  You would have to shift the shroud forwards to fit all of that in.  Or push very hard

Please confirm which parts you have installed in your shroud.  Rather than declare that my design is not compatible with the strip stack pack, and leave it there; I would be happy to create a version that is compatible with the Hjimoto parts.  Air flow just has to be managed, rather than let it do its own thing. 

If you removed the Hajimoto baffles and air stripper, then my design is compatible, except that it is not compatible with .25 power, using the thin walls I used for .22.  The thicker wall LDC already exists and is being tested on a .22 Avenger do to a lack of a .25 Avenger.

There are two versions.  The ribbed version with the tapering wall thickness might have more appeal than the one that has a 6 mm thick outside wall, all the way to the muzzle.   CAD Images below show them together.

[swingin]

I removed everything before installing this unit. No way to fit anything besides that, lol.

With the Tanto I cut the adapter almost all the way off so it didn't touch the Haji stack.

I think I like the plain better than the ribbed myself.

[subscriber]

Thanks Don, that points to too much flex in my previous design. 

Apart from the outer walls being 50% thicker, the internal walls are also much thicker on the versions shown above.

The ribbed version removes weight mostly from the front.  The triangulated ribs should keep the whole thing fairly stiff.

I believe all three caliber Avengers have barrels just over 11 mm in diameter, so that is what I am working with. 

[swingin]

Id go with whatever you think would be best for this unit. I appreciate all of your help!

I wish my air stripper was that tight, I had to use plumbers tape on it to snug it up.

[subscriber]

You can have a smooth version if you like.  I can also alter the taper on the ribs, if that is your objection.  The ribbed version may be more eye-catching, and that might be a reason not to choose it.

I find honeycomb patterns very attractive on printed LDCs, but they are not as stiff as triangles.  However, when it comes to shroud extensions I would use, the less eye-catching the better.

[swingin]

To me the stronger the better, I'm not looking for attention, lol.

[subscriber]

After reading this thread, a member asked me by PM if the Avenger Bullpup has the same barrel and shroud as the rifle version.  And thus, if the bullpup would accept the same shroud inserts as the rifle?

Based on the specs for barrel length and the images I captured from Pyramyd Air, it is highly likely that the bullpup version of the Avenger would accept the same shroud inserts:

https://www.pyramydair.com/product/air-venturi-avenger-regulated-pcp-air-rifle?m=5136
https://www.pyramydair.com/product/air-venturi-avenger-bullpup-regulated-pcp-air-rifle?m=671


I am replying here so that I can attach images as an overlay to help the comparison.  Note that I have made no attempt to improve the relative scale of the images I captured from PA.

Anyone with actual experience or certain knowledge on this topic, please weigh in.


(As an aside, we are in the test stages for inserts with better in-shroud alignment and greater resistance to clipping.  So silence here does not mean the project has stalled)

[fatmike]

I've got a bullpup Ive installed your plume .25 baffles on and it fits correctly. I havent had a chance to shoot it with me getting covid then the weather has been bad. I hope to get out thursday or friday this week and give the baffles a go on both my avenger bullpup 25 and my liberty 22. I've been made aware I might have problems with the .25 baffles but I'm going to give it a fair chance anyhow. Hope to have more information to you soon.

[subscriber]

Thanks, Mike

[swingin]

I got the new plume design installed yesterday for my .25cal Avenger. I had to remove 2 barrel bands, loosen a tri-rail and unscrew my shroud to get the Haji stack pack out. Got it all back together installed the plume and was prepared to sight it in. I like to draw a vertical line and a horizontal line in my pellet trap then start with windage, I took aim and fired and to my surprise I hit the line first try, shot a second time at the same line, hit it again so I moved on to elevation, took a shot and I'll be darn, I hit it first try, then shot the bullseye and bam, dead center! I can't believe I removed all this stuff and I didn't even have to move my scope not even one click! WOW! That's unheard of with these shrouds moving around so much. Fantastic work you guys! As for sound, Id say it's as quiet as a Tanto at a fraction of the price! As a bonus I got a few fill probe plugs, now I can fill without removing the plume, Nice touch guys! 5 stars all around, form and function! I am very happy with this setup, a tack driver!   

[subscriber]

Thanks for the feedback, Don

[swingin]

I think you hit this one out of the park with the new design my friend! Thank you VERY MUCH! I know you went through a bunch of designs, I appreciate all your effort you put in designing this! Fantastic job!

[fatmike]

I've still got to get out and test the previous design.  Between getting covid and snow storms it seems like I'll never get to it. I hoping I dont have the clipping issue the other guy had. Definitely well designed and printed. Both the avenger and liberty baffles sit tight to the shroud. I th I'm no after testing I'm going to need another for a liberty.  I've been reading up on 3d print and design and it's a lot to take in. Theres so much that can be done on a 3d printer I think I'd be doing myself a disservice to not give it a try.

[swingin]

Here's some fill probe end caps for order, I picked #1 because it has a textured grip and nothing to catch on if I were out in the bush. They are a friction fit that will not come off, very nice fitting. I also put a coat of flat black on all of them.

[subscriber]

I boosted the light on the caps a bit, Don; to show more detail.

[swingin]

I boosted the light on the caps a bit, Don; to show more detail.

WOW! Very nice! My camera is almost as old as I am, lol. Thanks Sub!