My new Diana Skyhawk

Just received my new Diana Skyhawk .25 in laminate. As I age I find carbines and bullpups are easier to continue shooting off hand versus long guns. I realize there are potential issues with a Chinese built airgun but have done a lot of reading about the Skyhawk/P15 and believe it was worth the risk. All I have been able to do so far is mount a scope, adjust the butt plate and shoot a 20 shot chrony’ed string. Had 10 inches of snow on the ground yesterday so did the shot string out the patio door! Waiting for some snow to melt so I can put a target on pellet trap (set at 25 yards) so I can adjust scope and check accuracy. I am pleased with the handling so far.



A little back ground on why I purchased the Skyhawk vs an Artemis P15. I wanted an adjustable stock because of my experience with shotguns. My Trap and Sporting Clay experience has reinforced the value of a good fitting gun. My shotguns have adjustable combs and butt plates primarily because my eye is the rear site on a shotgun so eye placement is critical. On a scoped rifle an adjustable stock allows you to repeatably mount the rifle to the same position so that you aren’t moving your head around trying to get a good scope picture. Even though the Skyhawk doesn’t have an adjustable comb I have been able to adjust the butt plate to get a repeatable mount with it. If I had bought the P15 I would have added an adjustable butt plate at a cost of 125 to 200 dollars installed on my rifle and I still would not have a better quality of wood. I felt the cost trade offs were justified.



Here is my first chrony string (JSB Exact King .25 at 25.39gr):


 
Congrationlations on your lovely Skyhawk.



I have the walnut .22 and have modded it with a 22 LW Poly choke barrel, longer shroud, Huma regulator screwed to Lee545’s plenum extension.



I love mine, enjoy your rifle.

Roachcreek

1572051275_13302743365db3994b1ce291.99502043_3E2CEDE7-C94F-48D0-880B-12BBF9823374.jpeg

 
sigp220 - The scope is a MTC Mamba Lite 4-16x42. I will try to post photo(s) tomorrow.

Roachcreek - I have read about the positive effect a larger plenum has had on other PCPs, so I'm interested learning about the positive benefits a larger plenum has on the Skyhawk. How many fps did your Lee545 plenum add to your Skyhawk and are there any other benefits beside increased fps?


 
My Huma was set at 130 bar prior to the plenum extension and hammer spring tension screw flush, Highest FPE obtained was 28 FPE. With Crosman hp’s it was shooting at 900 FPS for a lower FPE.

When Matt at JSAR installed the 20 inch barrel and Huma, he found this was just under maximum power with the Huma maxed and the hammer spring maxed, so the power was set in the 28 FPE range.

With the Huma pressure raised to 140 bar and plenum installed, I Max out at 46.7 FPE with 25.39 and 34 grain JSB’s.

Now here is the magic, the wide range of power I can access with the Lee 545 plenum. Now bear in mind my new plenum is full of 140 bar air and with the hammer spring maxed I get 46.7 FPE, but I don’t need to use all that air if I don’t want to. So if I dual the hammer spring back to flush, so the valve just sips at the 140 bar, I am within 50 FPS, 950 FPS, of where I was at with the Crosman hp’s BEFORE the plenum extension.

Best of both worlds,

Roachcreek
 
Rusty,



That original shroud is garbage, when you add those poorly stamped baffles it becomes rancid garbage.

When Matt installed my barrel he found the threads on both ends of the shroud were misaligned to the same degree, so any extension added to the shroud will cause clipping.

That was the 2nd reason I had a new shroud made, the first reason was I had a longer barrel.



Many owners just drop the baffles in a trash can and do the curler mod. Others do as you have and set the entire shroud aside and add a Donnyfl product. By having a new shroud correctly machined you have both options available.



Roachcreek
 
Had a little time to shoot for accuracy today. Group size at 25 yards is about 2.5" with a majority in a 1" hole with some fliers. My guess is there may be an issue with shroud and baffles as mentioned by Roachcreek. Have shot about 70 pellets, single shot tray, through it so far (rifle directly out of box - have not cleaned or adjusted). Still getting used to rifle. Will clean barrel and rerun accuracy tests later next week. Looks like we are going to have snow for the next few days so not sure when I'll be able to test again. Here are 2 pictures of the setup I used to test today.

1572124497_4468053935db4b751f16af5.00474363_Skyhawk 1a.png
1572124533_15207230605db4b775aa8164.24311721_Skyhawk 2a.png

 
Rustynuts

I had a FX Wildcat and out of the box it was an all around better rifle than the Skyhawk, but it never felt right (too heavy and unbalanced for me). The Skyhawk fits me much better and with help from the community may get close to the mechanical excellence of the Wildcat for me. When I bought the Skyhawk I anticipated that I might end up having the same amount of money in the Skyhawk as I had in the Wildcat.
 
I think either Huma or our own Lee545 would be a good choice. From what I have read, Huma says there are two variants of the p-15/Skyhawk air tubes, Huma needs to know which you have before you order. I believe the information is on their website. I had JSAR R&R my Huma,so I don’t know what hoops they had to jump through and Lee provided his plenum and installed it while making my shroud.

Not to be negative, but if you need to rebarrel that Skyhawk the best choices are in no special order, 25 Mrod GreenMountain , CZ, LW and TJ especially if you want to shoot slugs.


I think in the 22 and 25 a larger plenum is a must have. I think a 25 can hit the mid 50’s in FPE and the 22 with more spring will break 50 with little trouble.



you can use your chronograph to check fir clipping, the shots that are clipping will be slower. I would try the shroud without baffles to see if accuracy improves first.


My Skyhawk barrel had a tight spot right in front of the chamber, I lapped it but the improvement was not something I wanted to live with so I sent it to JSAR to rebarrel and install the Huma.



Roachcreek
 
Roachcreek

After reading about your barrel and other posts about the Artemis/Skyhawk barrels I talked with JSAR last week about a stock length LW barrel and they can machine a barrel to fit my Skyhawk without me sending in my rifle. Also JSAR is moving towards being an airgun manufacturer and moving away from doing airgun tuning (other than their own airguns). Because they are moving towards focusing on their own airguns I went ahead and ordered a LW barrel for my Skyhawk. I have had a great experience with JSAR over the last year or so. 

I will take out the stock barrel, clean and polish it with a combination of Kroil and JB bore cleaner then replace it while I wait for my new barrel. The hardest part has been trying to find a .25 bore brush. I did find some .25 bore mops that I will use. Any leads on .25 specific bore brushes and/or jags would be much appreciated. I also have a Patchworm cleaning kit that I will use for the final cleaning.

Once I remove the barrel for cleaning/polishing I will look at the baffles/shroud. I will probably have many questions after I see the disassembled shroud.

I do not have the ability to machine parts or port my receiver so I am looking at bolt on modifications that improve my Skyhawk. I do reload for powder burners so I do have good scales and precision calipers. This is the reason I asked about the Huma plenum after looking at their website. Ultimately I think Lee545's plenum would be better than the Huma because he would match it to the rifle he had in hand but I am looking for modifications I can do without sending my rifle out to be modified. Also, I have had good experiences with Huma products over the last few years.

Frank
 
Found .25 barrel brush. I looked for one about 6 months ago for my FX Dreamline Classic but couldn't find one. Now everybody has them. 

Took rifle apart today. Barrel is in rough shape. Both crown and leade have chatter marks from initial machining. There is drilling flash in the barrel where the air port was drilled into barrel. I know how to clean up the leade and crown but not sure how clean flash from air port. Anybody got ideas?

Also measured hammer spring adjuster depth from flush. It is in 0.189" from flush. Is this normal for an out of the box Skyhawk .25?
 
Vetmix

I do like your cannon reference. I remember reading that you have/had a P15 in .25. Also remember that you had to do a lot of work to get it shooting well. Was your leade and muzzle as bad as mine? When I swagged the barrel after cleaning and taking care of the flashing in the air port I was surprised. The pellet fell cleanly through the breech area and stopped at the rifling then pushed through smoothly to the choke area where there was more resistance. The pellet used looked reasonable. May only have to rework crown and leade.

I'm committed to the Skyhawk at this stage, but realized I might have these and other issues before I started down this path. I agree that folks that think they are getting a finished product on the level of an Edgun, Taipan or FX should look elsewhere. I doubt that I will end up with a Skyhawk that is as refined as the rifles you referenced. Also agree that it will never have the resale of those rifles even after expensive modifications to make it shoot decently. I do have a Leshiy .177 and a FX Dreamline Classic .25 so I understand what you are saying. All that aside I am having fun (sort of)!
 
I still have it and it’s and accurate shooter. It is currently shooting slugs. But sadly I don’t trust any part of it that I haven’t replaced. The leade on my factory barrel was cut too deep. My crown looked better than yours but was not cut square. That is something guy’s often overlook. They think because it looks clean it’s ok. It has to be cut square to the bore. That shows up when you chuck it in a lathe. 
 
My barrel, shroud tube, regulator and baffles were throwaways. But bear in mind I suspected they would be when I purchased the rifle.

After this project, I would not trust Spa/Diana to cut anything square.

Having said that, the side lever is smoothing out nicely, the trigger at this point is delightful and the safety works. I get just under 47 FPE in a 22, and shoot that power into nice round one hole groups with astounding quietness.

That and the fact that to me, and the minions that lust after that Minelli worm wiggling on the hook you speak of, it is the most attractive bullpup on the market.

The rifle grows on me with each use, for a while, negative comments made me wondered if I should have purchased a Cricket, or a veteran or one of the many FX’s, but most of them don’t have the performance this rifle now has or the quality of the replacement parts I have added, LW poly barrel, Huma regulator improved shroud or extended plenum but mostly they are just not as easy on the eye while attempting to equal that performance.

In the end, it is my personalized rifle, the only one like it.

Roachcreek










 
Here is my latest update on my Skyhawk. I have addressed the three areas that are common problems with the Skyhawk - shroud, barrel, and cocking lever pin. The stock barrel has been reworked and I have run a chrony string with it but have not shot for accuracy due to bad weather. I have a JSAR drop in LW barrel that I will install after I get the Skyhawk sorted out from a power perspective. My current configuration is listed below:

Current Skyhawk configuration:

Crown rework by local gunsmith (stock barrel)

Transfer port and leade deburred by myself (stock barrel)

Barrel polished with J-B bore paste by myself (stock barrel)

Replacement cocking lever pin (new design w/ knurl at top of pin)

Hammer spring backed out half a turn from as received

Air-fectivetuning shroud

JB3d cheek piece

JB3d Biathlon Lever Cocking Aid

MTC Mamba lite 4-16x42mm scope

FX No Limit scope rings



Parts I have but not installed:

JSAR drop in LW barrel

JB3d Triple Picatinny Cylinder Mount



Here is my current chrony string (JSB Exact King .25 at 25.39gr):

Stats – Average 789.97 fps

Stats – Highest 795.13 fps

Stats – Lowest 785 fps

Stats - Ext. Spread 10.14 fps

Stats - Std. Dev 2.96 fps