.22 Dragonfly Impressions; and 50 FPS gain from fire-lapping

[subscriber]

The Dragonfly is attractive and generally solid feeling, while also light and handy.  That is until you contact the skinny barrel near the muzzle and watch it deflect...  My impressions and brief adventures into instant improvements follow below:





After taking the new rifle out of the box, I found that I could not pump it more than once before it felt like I was going to break something; possibly myself.  This was with my right hand on the pistol grip and the left on the pump handle.  One pump produced a surprisingly loud dry fire.  That suggested the Dragonfly might be usable at fewer than 8 pumps.

While exercising the cocking handle with the valve open after dry firing, I could tell that there was a lot of preload on the piston, from being rammed against the end of the stroke when the pump handle is stowed.  In my estimation; too much preload. This was adding to the felt pumping effort, and perhaps pushing it over the edge of usability.   

There appears to be a rubber donut behind the piston that is squashed, so that most air can be pushed into the valve body, without risk of going solid "metal to metal".  I noticed that the connecting rod had holes around its periphery, and a locknut.  This is obviously to set the degree of compression.   See image below.

I easily undid the locknut and backed off the preload, such that the connecting rod's effective length was perhaps 4 mm shorter.  If this was too much, I could easily dial it back.

After this change, I could pump the rifle twice with my right hand on the pistol grip.  Three times if I was desperate.

I had looked though the barrel with the bolt open after shooting a number of oily cleaning pellets in front of RWS Hobby wadcutters.  This is possibly the roughest looking barrel I have seen, short of army surplus; from pre-WW1...

The bore looked perhaps 90% black and unreflective.  If this was due to dirt, it was very well attached. 

I decided to shoot a few pellets across the Chrony, just to get an idea of what speed they were doing.  I was pleasantly surprised that two pumps produced around 425 FPS with these 12 grain pellets.  Three pumps broke 500 FPS.  I was impressed; except for how hard it was to pump...

I did not feel like sticking my cleaning rod down the barrel; simply out of respect for the cleaning rod.  So, I hatched a plan to fire lap the barrel and see what that did.

At first, I used a Q-tip to generously dose the chamber with a 50/50 mix of JB compound and mineral oil.  I would then load and shoot a 12 grain Hobby pellet through it.  After a few of these; it occurred to me that I might not be getting enough contact pressure to make much impression on this drain pipe.  So, I loaded one pellet; a glob of dilute JB compound behind it; then another pellet.  The idea was that; on shooting, both pellets would be driven out together, with JB compound in between.

At this point I was mildly concerned about sticking the pellets in the barrel.  So I figured that 8 pumps were the rated max, and that I should use that.  The only way I could get to 8 pumps was to brace the but stock, and to grip over the barrel with my right hand, in front of the rear sight; directly opposite the pump handle.  I did not want to grab the barrel like this, as the resultant deflection made the front sight base muzzle attachment contact the pump tube.  I gritted my teeth, and shot 10 double pellet loads, with generous but dilute JB compound in between. 

In terms of that method of pumping the rifle; I figured there was not enough deflection to yield the barrel in that direction.  Also, my attitude was that if I bent the barrel, it would be replaced with something that actually had a reflective bore...  The other reason for my cavalier attitude is that this gun is destined to metamorphose into something else.

After putting in what felt like considerable effort, I shot a number of oily cleaning pellets backed by lead ones.  Then dry cleaning pellets, backed by lead ones.  The results were instantly noticeable, but rather disappointing:  The reflective surface area in the barrel doubled to a "whopping" 20%.  It would take a lot more of these JB shots to make the barrel look like a new barrel.  More than I was willing to do, right now...

Now, I like the idea of using a rigid projectile to do the lapping:  It should preferentially cut the high spots in the bore and leave the low spots relatively untouched.  Also, the breech should be cut a little more than the muzzle... 

That, in contrast to tight fitting JB compound soaked felt pellets; trapped on a skewer on a cleaning rod; compressed at the ends to expand it into hard contact with the bore.  Such laps are favored by many on this board, and very good results obtained.  Anyway,  I overcame my bias against "soft laps":  Specifically, the idea that that all surfaces are "cut" more or less evenly; depending only on the concentration of strokes in a given area and the "freshness" of the JB compound.  Also, the potential for rounding over sharp edged lands too much.

So, I hatched another method, that combines "hard" fire lapping with "soft" hand lapping:  I loaded one Hobby pellet via the bolt; then a felt cleaning pellet that had been very generously coated with undiluted JB compound.  Then another Hobby pellet was loaded, trapping the JB loaded felt cleaning pellet in between.  The felt pellets I used for this were close to .22 diameter; but were actually for .177 caliber; making them easier to load when coated in JB compound.

On firing at 8 pumps, the idea was for the rear pellet to squash the felt against the front pellet, such that the felt expanded vigorously; jammed the JB compound against the full surface of the bore, while dragging over it on the way to the muzzle.  The highest contact pressure would be near the breech, dropping off towards the muzzle, along with the air pressure.

The JB would also get "used up" on the way to the muzzle; so the bore would certainly not be cut wider at the muzzle by accident.

The fact that the rear pellet skirt had to do so much work, propelling the extra heavy, very draggy "sandwich" down the bore, would make the rear pellet skirt act as a hard lap; preferentially cutting the high spots.  The front pellet might might also act as a hard lap, but act more on the land tops.

I though that I would shoot just 5 of these "sandwiches" before cleaning up and taking a look.  Well, proponents of the felt wad sandwich lap may say "I told you so":  After so few shots, the gloss level improved to what I would describe as 80% reflective.  Not close to a mirror, but almost "white".

Happy with the improvement, and sore from the pumping, I decided to shoot a few single pellets over the chrony to see if it had made any difference:  The velocity at two pumps increased by a full 50 FPS; or +26% FPE.  Might more lapping improve things further?  Perhaps.  What about at higher pump counts?  From 5 pump on, the blast was loud enough that I decided to wait until a more appropriate time.  See velocity-per-pump table, below.

I could easily shoot a lot more JB paste "felt sandwiches"; but too many, and I would be concerned with wiping out the rather shallow looking rifling.  Then again; as long as one checks every five lapping shots, it probably could not do any real harm.  I would expect the improvement per fire lap session to taper off, as the surface area increased.  At some point, the pellets may be too loose; should one get carried away...

It is possible that loading abrasives via the breech this way is hard on the O-ring.  If so, the Dragonfly came with a full O-ring replacement kit.  The bolt does not have an abrasive induced circular witness mark from contact at the breech O-ring, so I am not too worried...

Single shot tray used throughout.  No need to gum up the magazine.


Anyway, I thought that some of you might find the above detail useful in some way.

[rsterne]

That is a very unique way to do fire-lapping.... The best thing is that it appears to work great !!!!

Bob

[subscriber]

Yes Bob.  The more aggressive polishing was inspired by your SOP; except in my case, it is all done by shooting.  I wish I could have taken a before and after picture of the bore. 


As an aside, it occurred to me that I may be dissing the product by posting this; as if there are many like it.

That said, there are a number of purchase reviews on PA stating their barrels were "hard to clean".   Even on GTA, early posters reported water in the compression tube and apparent rust in the bore.   

Also, the hard to pump aspect seems like a common experience.   Seems like an easy adjustment could make the out of box experience a lot better.

[Insanity]

That is a very interesting method. I have been looking into different pellets to firelap with but all of them have such small contact area. It seems to me it would take hundreds to effectively fire lap to desired results.

[subscriber]

Matt, I think that with this Dragonfly that is probably true - needing hundreds of pellets to make a useful impression.  If only the normal pellet bearing area is involved.

That said, the first least aggressive method I listed above took a shiny Slavia 634 bore to an absolute mirror, in with about a dozen applications of of dilute JB compound; with two pellets fired per Q-tip JB  application.  However, with this method, there is a "wave" of JB compound ahead of the pellet head and skirt, being swept along the bore.  So, not just the tiny bit that could be impregnated into the bearing area by rolling between steel plates.

The snag with a long lead slug, is that if it really made hard contact down to groove level, it would be near impossible to fire from a low power airgun.  It may works fine out of an airgun that could normally shoot such a slug at over 500 FPS (or a more "normal" slug velocity of 900+ FPS), rather than stick it in the barrel.

You must realize that what I am doing is not nearly as aggressive as Tubbs Final Finish fire lapping bullet system.  There, a number of bullets embedded with an almost invisible layer of abrasive, at decreasing grit sizes are fired at reduced velocities.  They start at 220 grit and go up to 600 or 800.  As far as I have been able to gather, JB compound behaves like 1200 grit abrasive.  It also breaks up fast, and acts "finer" as you use it (or goes down the barrel).

I have a Baikal SSP pistol that is very accurate.  Its bore is medium bright, but gathers no lead what so ever.  As it cost me almost $500 to import it from Europe, I would not be inclined to "improve it" by fire lapping of any kind.   I don't even use a cleaning rod or pull through on it.  Just shoot cleaning pellets - that seem to do nothing, because the barrel stays clean all by itself. 

In the case of the Dragonfly, such a rough bore was going to lead up fast, and accuracy would be short lived.  Desperate measures applied to a much cheaper platform.  Anyway, by being willing to pull out all the reasonable stops, I invented a new way to fire lap.  And I am very happy with that

[subscriber]

Captured velocities at 6, 7 and 8 pumps with 12 grain Hobby pellets.  Then at 8 pumps with JSB dome 15.9 grain.   See table below.   This is without any more fire lapping.

The Pyramyd Air spec for the Dragonfly is 630 FPS with 14.3 grain pellets, for 12.3 FPE at 8 pumps.  This suggests that my adjustment to decrease the piston "crush" or preload has not cost any performance.  It also suggests that backing it off further might meet the FPE spec, while lowering the pump effort closer to the realms of reasonable usability.  Perhaps my Dragonfly's compression setting drifted away from the factory setting, due to vibration in shipping.  The lock nut was not tight at all...

My .22 HW50S shoots the same can of Hobby pellets at a consistent 675 +-5 FPS, by means of one short, medium effort stroke.  This level of ease with the HW makes the Dragonfly's spring vibration free shot seem less attractive, by comparison.  If the Dragonfly was quieter than the HW, then it may regain some advantage.  However, from 5 to 8 pumps the Dragonfly's bark is louder, to much louder than the HW.

[subscriber]

For those of you who were wondering, what improvements might happen, if I repeated my JB compound loaded felt pellet sandwich fire lapping?  Well, I can tell you:

I shot another five lead pellet/JB coated felt pellet/lead pellet sandwiches.  The gloss level of the bore has increased just enough to be able to qualify as "bright".  The pellet velocities have stayed the same.

This tells me, that if you were considering using the above method, do not exceed 5 abrasive cycles.  There is probably no further benefit, and my barrel was very rough looking at the start.  No additional benefit; and potential unintended consequences:

Another reason for not overusing the fire lap felt sandwich method is the possibility of wearing a balloon shaped "pocket" just ahead of the chamber.  The entrance to the chamber would size the pellet down on loading, then unless the pellet skirt were expanded by the high pressure air blast, so that the skirt followed the barrel wall closely, air could leak by the skirt, as the pellet passed through the ballooned section.  This would then reduce pellet velocity, and possibly hurt accuracy due to yawing or rattling pellets...

Intuitively, I still prefer a tight fitting lead lap:  It cannot easily be over expanded to wear a significant balloon in the barrel wall.   It simply cuts more where the barrel finish "sticks up".  That said, I would not hesitate to use a limited number of the "soft" fire lap shots on another airgun, if it had really ugly looking bore. 

Another member contacted me, stating that, to improve rough bores fast, they use pellets lightly rolled between steel plates with 220 grit valve grinding compound.  The excess compound would be wiped off, so only that embedded in the pellet's bearing surfaces would be "active".  This certainly sounds better than shooting a bolus of coarse grit in front of the pellet. 

Cutting of the barrel steel would occur only when the pellet made hard contact with the bore.  It would do nothing to low spots.  I was assured that pellets "loaded" with grit this way do not leave large score marks.
 Rather, that they behave like much finer grit in terms of the finish produced.  I may try that on the next barrel that looks ugly enough to make the potential loss insignificant.

[Insanity]

I have beel looking at pellets with more surface area to do this with also just not ready for that just yet. One barrel is brand new and i dont know how it shoots the other barrel i would but waiting on umarex response to some defects.

[subscriber]

What about these, Matt?

https://www.pyramydair.com/product/seneca-22-cal-28-5-grains-domed-125ct?p=1468
https://www.pyramydair.com/product/eun-jin-22-cal-28-5-grains-domed-125ct?p=194

[Insanity]

Those are very high on my list.

[RBQChicken]

What's the actual head size of these pellets?  Would they work in a non-steroided 392P?  I'd love to have a super heavyweight pellet but I know my two 392p's prefer 5.52 mm heads at a minimum.

Those appear to be the same pellet.

[chwillbill68]

The Dragonfly is attractive and generally solid feeling, while also light and handy.  That is until you contact the skinny barrel near the muzzle and watch it deflect...  My impressions and brief adventures into instant improvements follow below:





After taking the new rifle out of the box, I found that I could not pump it more than once before it felt like I was going to break something; possibly myself.  This was with my right hand on the pistol grip and the left on the pump handle.  One pump produced a surprisingly loud dry fire.  That suggested the Dragonfly might be usable at fewer than 8 pumps.

While exercising the cocking handle with the valve open after dry firing, I could tell that there was a lot of preload on the piston, from being rammed against the end of the stroke when the pump handle is stowed.  In my estimation; too much preload. This was adding to the felt pumping effort, and perhaps pushing it over the edge of usability.   

There appears to be a rubber donut behind the piston that is squashed, so that most air can be pushed into the valve body, without risk of going solid "metal to metal".  I noticed that the connecting rod had holes around its periphery, and a locknut.  This is obviously to set the degree of compression.   See image below.

I easily undid the locknut and backed off the preload, such that the connecting rod's effective length was perhaps 4 mm shorter.  If this was too much, I could easily dial it back.

After this change, I could pump the rifle twice with my right hand on the pistol grip.  Three times if I was desperate.

I had looked though the barrel with the bolt open after shooting a number of oily cleaning pellets in front of RWS Hobby wadcutters.  This is possibly the roughest looking barrel I have seen, short of army surplus; from pre-WW1...

The bore looked perhaps 90% black and unreflective.  If this was due to dirt, it was very well attached. 

I decided to shoot a few pellets across the Chrony, just to get an idea of what speed they were doing.  I was pleasantly surprised that two pumps produced around 425 FPS with these 12 grain pellets.  Three pumps broke 500 FPS.  I was impressed; except for how hard it was to pump...

I did not feel like sticking my cleaning rod down the barrel; simply out of respect for the cleaning rod.  So, I hatched a plan to fire lap the barrel and see what that did.

At first, I used a Q-tip to generously dose the chamber with a 50/50 mix of JB compound and mineral oil.  I would then load and shoot a 12 grain Hobby pellet through it.  After a few of these; it occurred to me that I might not be getting enough contact pressure to make much impression on this drain pipe.  So, I loaded one pellet; a glob of dilute JB compound behind it; then another pellet.  The idea was that; on shooting, both pellets would be driven out together, with JB compound in between.

At this point I was mildly concerned about sticking the pellets in the barrel.  So I figured that 8 pumps were the rated max, and that I should use that.  The only way I could get to 8 pumps was to brace the but stock, and to grip over the barrel with my right hand, in front of the rear sight; directly opposite the pump handle.  I did not want to grab the barrel like this, as the resultant deflection made the front sight base muzzle attachment contact the pump tube.  I gritted my teeth, and shot 10 double pellet loads, with generous but dilute JB compound in between. 

In terms of that method of pumping the rifle; I figured there was not enough deflection to yield the barrel in that direction.  Also, my attitude was that if I bent the barrel, it would be replaced with something that actually had a reflective bore...  The other reason for my cavalier attitude is that this gun is destined to metamorphose into something else.

After putting in what felt like considerable effort, I shot a number of oily cleaning pellets backed by lead ones.  Then dry cleaning pellets, backed by lead ones.  The results were instantly noticeable, but rather disappointing:  The reflective surface area in the barrel doubled to a "whopping" 20%.  It would take a lot more of these JB shots to make the barrel look like a new barrel.  More than I was willing to do, right now...

Now, I like the idea of using a rigid projectile to do the lapping:  It should preferentially cut the high spots in the bore and leave the low spots relatively untouched.  Also, the breech should be cut a little more than the muzzle... 

That, in contrast to tight fitting JB compound soaked felt pellets; trapped on a skewer on a cleaning rod; compressed at the ends to expand it into hard contact with the bore.  Such laps are favored by many on this board, and very good results obtained.  Anyway,  I overcame my bias against "soft laps":  Specifically, the idea that that all surfaces are "cut" more or less evenly; depending only on the concentration of strokes in a given area and the "freshness" of the JB compound.  Also, the potential for rounding over sharp edged lands too much.

So, I hatched another method, that combines "hard" fire lapping with "soft" hand lapping:  I loaded one Hobby pellet via the bolt; then a felt cleaning pellet that had been very generously coated with undiluted JB compound.  Then another Hobby pellet was loaded, trapping the JB loaded felt cleaning pellet in between.  The felt pellets I used for this were close to .22 diameter; but were actually for .177 caliber; making them easier to load when coated in JB compound.

On firing at 8 pumps, the idea was for the rear pellet to squash the felt against the front pellet, such that the felt expanded vigorously; jammed the JB compound against the full surface of the bore, while dragging over it on the way to the muzzle.  The highest contact pressure would be near the breech, dropping off towards the muzzle, along with the air pressure.

The JB would also get "used up" on the way to the muzzle; so the bore would certainly not be cut wider at the muzzle by accident.

The fact that the rear pellet skirt had to do so much work, propelling the extra heavy, very draggy "sandwich" down the bore, would make the rear pellet skirt act as a hard lap; preferentially cutting the high spots.  The front pellet might might also act as a hard lap, but act more on the land tops.

I though that I would shoot just 5 of these "sandwiches" before cleaning up and taking a look.  Well, proponents of the felt wad sandwich lap may say "I told you so":  After so few shots, the gloss level improved to what I would describe as 80% reflective.  Not close to a mirror, but almost "white".

Happy with the improvement, and sore from the pumping, I decided to shoot a few single pellets over the chrony to see if it had made any difference:  The velocity at two pumps increased by a full 50 FPS; or +26% FPE.  Might more lapping improve things further?  Perhaps.  What about at higher pump counts?  From 5 pump on, the blast was loud enough that I decided to wait until a more appropriate time.  See velocity-per-pump table, below.

I could easily shoot a lot more JB paste "felt sandwiches"; but too many, and I would be concerned with wiping out the rather shallow looking rifling.  Then again; as long as one checks every five lapping shots, it probably could not do any real harm.  I would expect the improvement per fire lap session to taper off, as the surface area increased.  At some point, the pellets may be too loose; should one get carried away...

It is possible that loading abrasives via the breech this way is hard on the O-ring.  If so, the Dragonfly came with a full O-ring replacement kit.  The bolt does not have an abrasive induced circular witness mark from contact at the breech O-ring, so I am not too worried...

Single shot tray used throughout.  No need to gum up the magazine.


Anyway, I thought that some of you might find the above detail useful in some way.

This is great! Thanks for posting it. Mine is just like yours. The shots move around also.  Would like to do the adjustment on mine for pumping. Wondering if you could PM me your pic of that. I had trouble seeing it well in the pic on here. I am very visual when trying to do something, so I was really looking at it but its a bit blurry for me.

Thanks Bill C!

[subscriber]

Bill,

Click on image below to enlarge it.  The lock nut is part #59.  The rod #58 has a series of dimples around its periphery that can be used to turn it.  The dimples are not shown in this view, but are obvious in good light, when you have the pump lever open on your Dragonfly.  Sorry about the fuzzy image in my OP.




If you battle to release the locknut (mine was not tight), removing the pump arm hinge pin (part #29) will allow you to use the cocking linkage as a part-turn driver, while restraining part #58 via an exposed dimple with a punch, Allen key, or similar close fitting tool.  The lock nut has to be broken free by screwing the rod assembly as to "make it longer", before you can impart relative motion that would make it "shorter".  Then set the lock nut.

The cocking arm hinge pushes out with finger pressure, after the endcap is removed.  The endcap (part #25) has two tiny screws holding it in place.

The pump arm must be "open" for you to remove the hinge pin.  Else the pin has too much load on it...

[chwillbill68]

Bill,

Click on image below to enlarge it.  The lock nut is part #59.  The rod #58 has a series of dimples around its periphery that can be used to turn it.  The dimples are not shown in this view, but are obvious in good light, when you have the pump lever open on your Dragonfly.  Sorry about the fuzzy image in my OP.




If you battle to release the locknut (mine was not tight), removing the pump arm hinge pin (part #29) will allow you to use the cocking linkage as a part-turn driver, while restraining part #58 via an exposed dimple with a punch, Allen key, or similar close fitting tool.  The lock nut has to be broken free by screwing the rod assembly as to "make it longer", before you can impart relative motion that would make it "shorter".  Then set the lock nut.

The cocking arm hinge pushes out with finger pressure, after the endcap is removed.  The endcap (part #25) has two tiny screws holding it in place.

The pump arm must be "open" for you to remove the hinge pin.  Else the pin has too much load on it...

 Awesome, thank you very much!!

[Horatio]

This design looks like it could benefit from a rigid barrel band in front of the pump tube, if that makes sense.

[xtred1]

I have had mine for a while. ( It is in .22) It had to go back to PA twice to get it loading pellets properly.  They repaired and sent my gun back. (that is to say they did not just send me a new gun) Mine was hard to pump at first. I removed the rear sight and brace off that mount, it has become easier with use.  I run a TKO on it as it is pretty loud. The barrel does get bumped from time to time but it holds a zero fine. I had hoped they had gotten better with later batches of guns after I saw PA selling refurbs for less money. Nice design just a little more work to get them running out of the box like they should. I hope your info helps others with their guns.

[subscriber]

I single  load mine, and can feel the pellet "catch" before the bolt fully closes.   When I capture pellets that were shot with one pump stroke in soft media, they clearly shown the pellet nose catching on the edge of the transfer port.  It must have a very sharp edge there...

I have not even tried feeding from the mag.  My attitude is that mag feeding for "fast reloading" is nonsense, when it takes so long and so much effort to pump up the rifle - it makes much more sense as the PCP variant, the Stormrider .  Fortunately, the Dragonfly's breech's loading port (and single shot tray) are very user friendly.

[xtred1]

I single  load mine, and can feel the pellet "catch" before the bolt fully closes.   When I capture pellets that were shot with one pump stroke in soft media, they clearly shown the pellet nose catching on the edge of the transfer port.  It must have a very sharp edge there...

I have not even tried feeding from the mag.  My attitude is that mag feeding for "fast reloading" is nonsense, when it takes so long and so much effort to pump up the rifle - it makes much more sense as the PCP variant, the Stormrider .  Fortunately, the Dragonfly's breech's loading port (and single shot tray) are very user friendly.

That is what mine did tell I sent it back to PA twice. Now it is smooth loading. Once they get broken in they pump much easier. I only shoot rats at night. The mag makes handling the pellets at night way easier.  I use 3 pumps to shoot rats. I had to take a 2nd shot on a rat a while ago. I was able to get three pumps into the gun fast enough to get that 2 shot off.  If I had a good place to host a video I would make one on how easy mine pumps now.

[subscriber]

Makes sense, Paul.  Fumbling with pellets in the dark is no fun.

While pumping, do you grip the the pistol grip with one hand, or over the barrel (opposite the pump handle)?  Do you brace the butt-stock against something? 

I can get two pumps gripping the pistol grip, "floating" the rifle midair, like one might with a springer.  For three pumps, I have to at least brace the butt-stock against the side of my leg.  For more than 3 pumps, I have to grip over the barrel, directly opposite the pump handle.  This while resting the butt-stock on a table or other horizontal surface.

The good thing is that is that 2 or 3 pump strokes make usable power for short range shooting.

[xtred1]

Makes sense, Paul.  Fumbling with pellets in the dark is no fun.

While pumping, do you grip the the pistol grip with one hand, or over the barrel (opposite the pump handle)?  Do you brace the butt-stock against something? 

I can get two pumps gripping the pistol grip, "floating" the rifle midair, like one might with a springer.  For three pumps, I have to at least brace the butt-stock against the side of my leg.  For more than 3 pumps, I have to grip over the barrel, directly opposite the pump handle.  This while resting the butt-stock on a table or other horizontal surface.

The good thing is that is that 2 or 3 pump strokes make usable power for short range shooting.

I keep the butt-stock on something I have removed the rear sight. I use that mount as a pump platform.  As you can see in the photo I put the knife edge of my had against the scope and the palm of the hand over that rear sight mount.