Fuxineering My Vulcan 0.22 from Talon Tunes
Thanks to the old timers here, I am starting to get my recently arrived Vulcan 0.22 from Tony readied for use.
My apologies if I don’t credit people correctly. Still trying to learn who is who.
Mine is a 2015 June production with an odd configuration of features. It has the multi part baffle shroud like the new guns, but lacked a depinger on its hammer spring, had the old style two hole HST adjuster like the older production, but like the current guns came with no hard case.
First order of business was getting its safety to actually engage. It would only partially engage and if one pulled the trigger a little harder, the blade would slip past safety and fire the gun. Turns out the trigger blade didn’t leave enough clearance for the safety plate to slide between it and the frame. The safety was just barely engaging the trigger blade and would refuse to slide further back. It was working more like a sear than a safety. Adjusting the linkage rod tension got a bit more clearance and after running the safety back and forth it now actually engages. Currently, the safety is stiff, but I put a tiny dab of moly grease and it is gradually working looser. I guess I could grind the safety plate thinner, but that means taking apart more stuff that I want to do.
Next, I turned to Hoot’s shroud vent mod. On my particular shroud, the front cap was easy to unscrew with a lens wrench.
The rear cap wouldn’t budge, so I did all the work only from the front and didn’t try removing the back flow baffle (rearmost element)
Here we see all five baffles, their intervening O-rings and the front cap
While I had things apart, I grabbed a few measurements. The baffle opening is 0.243.
The front cap opening measured 0.258
Given that a 0.30 wouldn’t fit, I’m guess the baffles and cap different for the bigger caliber version.
Then again, we see SniperQTY happily swapping barrels of different calibers on U-Tube.
Don’t know if he also swaps the shrouds.
Shroud outer diameter = 1.130
Shroud inner diameter = 1.116
I used Donny’s tape method to protect the shroud and allow easy marking of the desired hold locations.
An auto punch makes easy, accurately divots in the aluminum tubing. If you are still using an old style center punch,
do yourself a favor and get an auto punch. I kick myself for not getting one years ago.
Mine is a Lisle 30280 Automatic Center Punch. Works great.
A few minutes at the drill press and 1.0 mm holes were done.
UPDATE/ my shroud’s rear holes are now 1.0 mm and forward baffle holes 1.5 mm /UPDATE
TIP: since this is only aluminum, use 90% isopropyl alcohol to lubricate and cool the bit instead of cutting oil.
Cleanup is a LOT easier without oily residue.
(That would be the high concentration stuff, not regular rubbing alcohol)
Deburring the inside of the drill holes was done with a piece of all thread.
I taped most of the rod to limit what portions were sharp. A few passes and
all the burrs were gone. The baffles slipped easily back into place.
Finally, the vented shroud ready to install. I used an O-ring like Hoot said to secure the shroud in the desired spin.
You can’t even see the vent hols with the shroud spun to position
the holes between the shroud and barrel.
Muzzle report was now much quieter than the hammer slap and ping. Hmmmmm. was it possible that my new Vulcan didn’t have a factory de-pinger?
The lack of a hard case suggested it was a later gun, but the old style HST adjuster made me suspicious.
Opened up the access panel and sure enough —— no de-pinger at all.
Since I had to take it all apart, I went ahead and polished the hammer. Took just a few minutes with a dremel, felt wheel, and all metal polish.
Tried ONE grommet in the position that the factory places their de-pinger.
BTW, nobody quite explains how to get the whole assembly back into position.
You can’t push the spring and grommets through the adjuster hole.
Compressing the spring and hammer all together and squeezing
everything in from the side threatens to bend the hammer spring.
Here is how I did it without stressing the spring or scratching up the hammer.
1. Detach the cocking spring
2. Put the hammer, brass guide, and grommets together WITHOUT the hammer spring.
3. Insert the hammer assembly
4. Push the hammer spring in from the back. When you have enough pressure, the
grommets pop onto the spring. Then you simply spin and ease the grommets into position.
5. Reattach cocking spring
6. Insert HST adjusting plug.
Still pinged too loudly for me with one grommet, so back apart it went and I put on a second grommet.
Two grommets made the ping a bit softer. The hammer slap is now the loudest noise. Overall, the noise level has gone from loud as my Benjamin NP2 to about half as loud.
Mind, you, it is far from silent, but it is a significant improvement from how the gun arrived and worth the effort.
A delrin spring guide may be in my future.
EDIT: I have since gone to one grommet and a rubber cap over the brass bushing. See later in this thread.
Thanks all again for the info on this forum.
Guy
All Replies
:rofl: :rofl: :rofl:
guyko you need to work on your wife more, too much time spent on the gun
Fixed another annoyance today, not the Vulcan itself, but the grossly inaccurate magnification scale on my Hawke scope. Since I do so much of my practice and fine tuning at specific distances and magnifications, it is important to know what the actual magnification is when estimating hold overs. The factory scale was WAY wrong going from 8 – 32 x. The actual, measured mag range is 7.7 to 25x. That makes for a huge holdover error at shorter ranges and high magnification during target practice.
Now it has a properly calibrated scale
Process took several steps.
First I drew known size targets (50 mm, 30 mm, 15 mm) and set the gun at a know distance. Chair gun makes it easy to know how many MIL Dots a target should be at specific magnification and distance.
Basically followed the procedure for printing out a custom parallax scale.
The following image shows some of the process progressing from left to right.
Printed out a graduated strip and taped that over the scope’s existing scale.
Dialed in the magnification until each desired size matched the expected MIL Dot size. Then, marked the strip with where each size was correct.
Go back to the graphics program. Isolate the indicated rule lines and added numbering.
Finally, invert everything to white and put over a black background.
Print it out. Test fit. Adjust. Repeat until correct.
On the final version, cover the printout with packing tape to act as a water proofing barrier.
Cut the strip out with a paper slicer.
Attach to scope with rubber cement. Add some tape over the ends as additional protection.
The result looks like a factory made scale, but now it is actually correct.
:thumb: Way to go guykuo. Now you have taken it to another level. GREAT JOB :thumb:
Switching to right handed bolt was a big improvement also.
Besides right side I had smoothed mine with hones as someone had suggested. But now I’m thinking of kris’s suggestion of replacing the slotted plate with a see thru lexan plate. I wish I had better tools to work the lexan though.
I’m also thinking of making the slot slanted down forward slightly to follow the natural motion of the arm and hand. It’ll take me forever but when this record breaking heat wave passes Ohio I’m looking forward to a lot of snow and shut-in project time.
What I didn’t expect is how much nicer the cocking action is now. It wasn’t bad before. I THOUGHT it was
smooth, but now the knob glides into position like wet ice.
The slot edges come from the factory merely painted. The underlying metal edges are not that smooth.
Only a small portion of the edges engage with the knob shaft and it’s almost like a dull knife cutting
into the knob shaft.
Steps
1. Removed the u-plate
2. Filed the slot edges to remove existing paint and smooth out irregularities in the edges. I took care to
preserve the paint on the flat surfaces of the plate. Only the edges were smoothed. The profile I created
for the edges was slightly convex. The linear runs were made straight as possible.
3. Progressively polished the edges with sanding sticks all the way down to 10000 grit
4. Cleaned the u-plate
5. Sanded out nicks in the knob shaft and polished that too down to 1000 grit.
6. Reinstalled u-plate and knob
7. Lubricated edges and knob shaft with Dry-Glide (super messy & slippery stuff when wet out of bottle)
Tried cocking and and locking the down the knob in both positions.
I was totally shocked at how smoothly and easily it now falls into the locked positions.
I was trying to reduce wear, but the improved feel is a great bonus.
Did mine almost directly. The stamped edge is sharp, harsh and ratty but little Dremeling does wonders.
I can almost remember how smooth mine cocked.
I noticed some wear on the knob shaft and decided to polish the u-slot edges to reduce ongoing wear.
What I didn’t expect is how much nicer the cocking action is now. It wasn’t bad before. I THOUGHT it was
smooth, but now the knob glides into position like wet ice.
The slot edges come from the factory merely painted. The underlying metal edges are not that smooth.
Only a small portion of the edges engage with the knob shaft and it’s almost like a dull knife cutting
into the knob shaft.
Steps
1. Removed the u-plate
2. Filed the slot edges to remove existing paint and smooth out irregularities in the edges. I took care to
preserve the paint on the flat surfaces of the plate. Only the edges were smoothed. The profile I created
for the edges was slightly convex. The linear runs were made straight as possible.
3. Progressively polished the edges with sanding sticks all the way down to 10000 grit
4. Cleaned the u-plate
5. Sanded out nicks in the knob shaft and polished that too down to 1000 grit.
6. Reinstalled u-plate and knob
7. Lubricated edges and knob shaft with Dry-Glide (super messy & slippery stuff when wet out of bottle)
Tried cocking and and locking the down the knob in both positions.
I was totally shocked at how smoothly and easily it now falls into the locked positions.
I was trying to reduce wear, but the improved feel is a great bonus.
I’ve been using a rubber cap over my brass bushing until now because that was all I had available.
I didn’t have a lathe and it seem awfully weak to have someone make a simple plastic bushing.
Today a bolt, nut and some mild abuse of my drill press let me turn a bushing for myself.
I won’t recommend the methodology, but surprisingly it worked.
On my bushing, I made the front, shoulder portion a thicker and larger diameter to better survive the blows.
Comparing a delrin bushing vs brash bushing / rubber cap I have been using…
The hammer impact and spring twang are about the same as with the rubber tip.
FPS is a bit higher at the same HST setting compared to the rubber cap.
The rubber cap has been holding up pretty well, but I can see some wear after 600 rounds. From what other forum members have experienced, delrin seems to hold up indefinitely.
Plus, I like having the spring guide portion a tad longer. The only gotcha was the bolt was oddly difficult to lock far enough back to lock the rear position. I had made my busing a little too long and it was running into the HST adjuster. Filed off a bit of my bushing and all is well.
.
Oh, he uses the Rubber Booty daily. I wonder how long it’ll take before that activity becomes illegal though..
Each to their own.
Good going guykuo :thumb:
I wonder if there will be a wear or deterioration factor ❓
Still using the rubber booty I see. That appears to be holding up well. Time for me to order a couple of the parts you’ve come up with ❗
As I started to read you current post I imagined you were putting an ear foam sleeve on the forward hammer extension. 🙄
Today’s experiments were
1. Test if padding the tip of the hammer improved hammer slap noise
2. See if hammer spring twang is better damped with something other than a rubber grommet.
First I tried putting a small rubber cap on the striking end of the hammer. The rubber cap gave about 1.5 mm of cushioning — too much. The hammer could transfer enough kinetic energy to open the poppet valve. After a few test firings, the pellet unceremoniously fell into the shroud and rattled about. So, next I tried something thinner. Two thickness of electrical tape on the hammer tip. The gun fires but about 100 FPS slower and the hammer slap really wasn’t that much better. I’m not convinced this is a good trade off so out cam the electrical tape. BTW after about 5 shots the tape had hole punched through it by the poppet valve pin. It’s going to take something really thin and tough to last there. The sound wasn’t really improved and I lost FPS that could not be adjusted out with more HST tension.
End of experiment 1 – Padding the tip of the hammer not a good mod.
=====
Experiment 2 – Can we improve hammer spring twang damping with an alternative material other than a rubber grommet.
After reading about spring noise in AR’s and how some silent springs have an “advanced polymer” damping system, I looked for a more complaint but light material.
I found something that works! A Flent’s Super Sleep foam ear plug damps better than my rubber grommet.
This particular foam ear plug is a super soft memory foam. It’s softer than others I’ve had and comfortable to sleep with them in your ears.
First I punched a hole in the foam ear plug. (Squish it flat and use a leather punch a couple times to make about a 1/4 inch hole)
Initial testing was clamping the hammer spring at one end with a needle nose plier and striking the spring with a metal probe to elicit the familiar spring twang.
Put my usual rubber grommet on the spring and repeated. The twang was damped, but still present.
Changed to the foam ear plug (same position as rubber grommet). The twang was pretty dead.
Back into the Vulcan and now my spring twang is way less. Instead of the spring twang, I can now hear a higher pitched ping that I think is the air tube.
End of Experiment 2: A Flent’s Super Sleep ear plug is a superior spring twang damper than my my rubber grommet.
Ironic how getting rid of one sound unmasks the next one. Will eventually have to explore de-pinging the air tube and/or the regulator spacer.
[quote=”kris”]thanks for trying!
with our power limits here, I still don’t quite get it why you cant give up 50-100fps. it would double your shotcount.
Kris, it’s because we don’t have to……. and most people over here have their own tank and don’t give a rats ass about shot count. At least I don’t. I take a tank where ever I go just incase the shootings good.
I’m thinking that the hammer spring and poppet spring have a common harmonic or combination of similar 1st and or 2nd and or 3rd harmonic. That is why the twang is so long and why grommets as dampers on the hammer spring do reduce the length of the noise. A fairly thin and hard rubber disc between may proportunately reduce the force of rebounding hammer poppet strikes. The compact design of the housing eliminates use of any different type of spring that would have less tendency to oscilate.
How about a rubber disc cut from an old pair of Totts?, slip on boots ❓
Thanks, it is an interesting mechanism and I try to avoid anything that is irreversible. Get information, make advancements, but hopefully not fux it up.
As I see it there are two mechanisms of hammer slap that can be worked on.
a. Secondary, excess impact by pats of the hammer other than that portion needed to open the poppet valve.
b. Direct impact noise of the hammer upon the poppet valve.
The first has been addressed by the o-ring mods on other style hammers. However, my testing today with a large diameter washer suggests that there isn’t an extraneous portion of the hammer striking. The leading probe diameter of the Vulcan hammer is small. It hits only the poppet valve. My washer merely reduced the total strike energy and that we can achieve by just turning down the HST.
The second is probably how the Vulcan generates most of its slap noise. Not only does the hammer strike metal against metal, but in the Vulcan, the tip of the hammer seems to be a hardened inset. That’s super hard metal against metal.
I agree that somehow putting a softer impact interface might let us reduce this noise while preserving FPS (with a slight increase in HST). However, I have yet to think of a good material that will be both tough enough to withstand thousands of hard hits on a tiny area AND be soft enough to make a good noise reduction. The cushioning would of course slightly slow initial poppet opening and might alter lock time. It remains to be tested if a good material can be found. Maybe a piece of car tire rubber?
Another mechanism that might be worth testing is to reduce the valve spring tension so we can get the same air flow opening with a lighter hammer strike. That’s going to take someone who is happy working inside the air chamber. While I could do that, I’m still a newbie who is hand pumping. Degassing and refilling the cylinder would be a big work investment. Things will change when my compressor and tank arrive, but that is probably in January.
Meanwhile, I will keep enjoying this Vulcan both in how well it shoots and tinker carefully with its wonderfully easy to access and understand mechanism.
It has to shoot well. The quietness, length of shot string, energy level don’t mean a thing if I accidentally do something to mess up accuracy and precision.
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I’ve always been so-so with all the Hawke scopes. The quality is fluctuating – to say the least. My friends Sidewinder Tac when set at its max mag at 25x corresponds to my three Delta’s at between 21-22x. You get what you pay for. The only two Chinajunk i like is the MTC Connect and Vector Paragon with its German glass. Eventhough second sortiment the glass easily beats any Chinese “first grade” glass. I don’t even consider Chinese scopes any longer. Crap at its finest …