Testing new discovery

[KnifeMaker]

Now "That's" an Endorsement!

[Hobbyman2007]

I made a second version this morning using the same basic design as my last version only this time it screws into an Evanix shroud with the end cap removed . This one is 1” OD aluminium tube by 4 3/4” long (3/4” threaded ) the inner sleeve was machined from a solid piece of delrin with orings at either end and filled with steel shot from a worn out dead blow hammer with a total weight of 115 grams  . The through hole is 3/8” and should have plenty of room for a .257 bullet to pass without clipping . This one I didn’t fill with oil as it’s getting mailed out to Knife for testing . Here are a few pics . As you can see the OD is pretty close to flush with the metric shroud , I mocked it up using my Air Speed for fittment .

[aceflier]

Very nice! Now we need someone to male them for the marauder shrouds and hatsan QE!

I tried my quick version with the 43gr bbt. It didnt seem to help no matter where I placed it. So I will test NSA 39gr next they shoot decent but not 1 hole at 20yds like I want.

[Hobbyman2007]

Tim , might I suggest you put more shot in your device .

[anti-squirrel]

Stiffer barrels will oscillate at higher prequencies. 

Also, if I remember my mechanical theory from Nuke Power School, the correlation between electronics and dynamic mechanical systems are equivalent, so what applies to one applies to the other.  So...

I'm now thinking a toroid "doughnut" screw-on vibration damper with a draincock.  Add some mass-heavy fine shot, then add the oil (or fluid) of your desires.  Make it standard LDC thread, with a female thread on one side and male on the other, so the LDC can still be used.  It doesn't have to be big or large, just enough inside the doughnut's void to store some oil and some shot or similar.  Suddenly you have a small device than be used across a wide variety of devices.  Keep the shot weight constant and change viscosity of the fluid to adjust for the vibration.   I'm not sure which is better suited to higher frequency vibration- gut feeling tells me the more viscous fluids.


EDIT: now upon thinking more about this and what little I recall about wave theory, you don't want a long MAD at that allows for creation of resonance at different frequencies along different points on the length of the barrel.  You want to stop the "whip" cold, so a shorter/heavier and perhaps "taller" doughnut?

[aceflier]

Tim , might I suggest you put more shot in your device .

I have plenty and its easy to add remove shot or oil. I’ll play around with it.

[nervoustrigger]

A very rigid body transmits high frequencies better than a softer (more lossy) body.  I would reason a high viscosity (no viscosity) is analogous to a rigid body, thus not well suited to damping vibration.

[Back_Roads]

 
 When I get around to my build,I am thinking of testing different weights of R/C shock oil. I also wonder if temperature extremes could change the performance.

[nervoustrigger]

One of the articles posted recently pointed out that silicone-based liquids are one of the least influenced by temperature.

[HunterWhite]

Just make sure that it doesn't freeze at the winter low temperatures.

[rsterne]

Hydraulic Oil is also available in many grades, with a viscosity from 7 to 1500 at 40*C (the ISO number is the viscosity at that temp, 100*F)…. However, it may be difficult to find in all grades in small quantities, it is often sold in 5 gal. buckets.... 

Extreme temperatures will, indeed, change the viscosity.... which is why multi-grade engine oils were developed for automotive use.... They have a higher Viscosity Index (less change with temperature)....

Bob

[jarmstrong]

clamps
https://www.opticsplanet.com/advanced-technology-mag-clamp-accessory-clamp.html
https://www.opticsplanet.com/advanced-technology-mag-clamp-accessory-clamp.html

[Hoople]

Knife, I’m all in. Like some, I was somewhat skeptical at first, but not now. I had to try your discovery for myself, and was blown away. Wow!
We are having almost constant rain, so I set an ironing board (best I could come up with) on my front porch with a heavy sand bag on top as a bench. Set out a target at 50 yds. Shot several 5 shot groups with my .22 FX Dreamlite. The heavy bag helped steady things up. Still it took several groups for me to settle in. From the picture, the three bottom groups I shot without your discovery. I do general do better, usually about .4”-.5” but as I said it took a while to get settled in. The top two groups I shot with my version of your discovery, I came up with #1 .275” center to center; POI shifted quite a bit low right. #2 I gave a few clicks up and left same POA .245” center to center. That is the best groups I have ever shot with anything! Amazing!  I ran out of time but will certainly be doing more experimenting. Can't wait to see what becomes available.
Specs as follows: The stabilizer I used is from my @=S+S%^$# days in the 1990s, and is oil (?) filled. It did a good job, with an extension of taming a short little Mathews hunting bow I had.  No markings on it, so brand or model is a mystery.
1” dia. steel tube with aluminum end caps
3 3/16” Long
3.2oz wt.
The bracket I made from a steel bar. I drilled and tapped it 1/2”x20 to fit my Dreamlite barrel threads. I put an o-ring on barrel threads before screwing on and snugging up on the barrel. I drilled the bar 1/4” and used a 1/4” screw to mount the stabilizer on the bar.
4.8 oz. Total wt. for mount and stabilizer
.22 FX Dreamlite
18.13 gr. JSBs straight out of tin
900 fps
Light rain falling 0 wind

[Nvreloader]

Thanks Charles

I have spent the last couple of days researching these type of archery stabilizers,
and have found out that they are also filled with some form/type of powder, as too what type,
I have not found out so far.

Tia,
Don

[KnifeMaker]

ThankYou Charles.


it seems more and more people are finding success with these. I had no hope of it working with pellets. Wasn't even on ny radar.   I'm very happy to be wrong.  [size=78%] [/size]

[KnifeMaker]

ThankYou Charles.


it seems more and more people are finding success with these. I had no hope of it working with pellets. Wasn't even on my radar.   I'm very happy to be wrong.   

[Hoople]

Thank you for sharing. Maybe I just got lucky, don't think so. I think you have hit on something transformative for airguns, and Donny missed the boat.  Time will tell.

[darkcharisma]

Thank you for sharing. Maybe I just got lucky, don't think so. I think you have hit on something transformative for airguns, and Donny missed the boat.  Time will tell.

Charles, go do a 100 yard test with and without the device and see if that shows significant results. 😁

[anti-squirrel]

I'm curious how these will affect rules on matches like EBR and 10-meter and FT

Also curious if anybody has tried setting one in vertical versus horizontal orientation.

[Hoople]

darkcharisma, if the rain lets up here and I have some time to shoot I am going to do some 75-100yd testing. I have a nice 100yd rifle/pistol/airgun range set up here on our small farm, but my bench is uncovered. I was planning on building a small shed to cover it this summer, but life keeps getting in my way.

I am curious to see what my Dreamlite with/without will do at longer ranges too. When I do shoot I''ll post the results.