Diana Skyhawk/ P15 what is the maximum FPE that you can reach in cal 22

[Broken_WV_Guy]

My thought was to simply increase the plenum volume, drill out the transfer port from 5mm to 5.5mm

Don't drill through... drill 3/4 of the way and then elongate the last bit forward, putting a little radius on it for better airflow without feeding problems. Never make the port wider where the pellet slides across it. The following picture is exaggerated for clarity. You can't get that much radius on it but you get the idea.

You have to be careful with that radius. You want to be sure the transfer port does not extend past the pellet skirt. I believe when I checked the Gauntlet's port there is no room to extend the port forward without compromising the pellet skirt seal.

I understand what you're saying. Thanks for pointing it out! 

How much benefit is there to drill out and then radius the TP then? This gives me 2nd thoughts on drilling it out.

What about polishing the lands in the barrel? Would less friction yield more ft-lbs than drilling the port?

All of this is for nothing if the accuracy isn't as good, imo. Accuracy to me is more valuable than power. I want to get more power to shoot a higher BC slug so that it's more accurate.

 

[heavy-impact]

I understand what you're saying. Thanks for pointing it out! 

How much benefit is there to drill out and then radius the TP then? This gives me 2nd thoughts on drilling it out.

What about polishing the lands in the barrel? Would less friction yield more ft-lbs than drilling the port?

All of this is for nothing if the accuracy isn't as good, imo. Accuracy to me is more valuable than power. I want to get more power to shoot a higher BC slug so that it's more accurate.

I can't put an exact number on it but I know drilling the port to bore size will let pellets tip into the port. Polishing the barrel is good but don't over do it. Too much polishing increases surface area to the point that it causes more friction.

 

[Sonnycruz]

how do you get a hold of Lee for plenum extension? I've tried searching vash545 and lee545 and get nothing. I have .25 skyhawk with huma @140 shooting 25.39@840. Want to see if I can get more with less reg and better efficiency thank you.

 

[Roachcreek]

PM is how I found him, he is a member here. I checked my messages to Lee545, his pm address is listed as deleted, whether that was me or the forum I have no idea. He is also on the gta. But I have not seen anything from him lately.



My last communication to him he was very busy at work.





Roachcreek

 

[jarmstrong]

my 25 cal P-15 with a 23+" LW barrel and Lees plenum ext will do 33gr at 850 fps IIRC the 25 gr do about 930 fps

I do not recall what my reg is set at, I would have to shoot a string over the chrony to find out for sure but I believe I left it at factory setting

if you can not reach Lee there always is Huma https://www.huma-air.com/Artemis-P15-Power-Tune-Regulator-XL-Plenum-Set

[email protected] try this ,, I don't know, maybe

 

[MBG]

I have Lee's plenum and was involved in the testing of Huma's Power Plenum, however nobody got it all right, as the plenum took up valuable real estate in the Airtube. I just got three of these from extreme airguns in South Africa, shipping not expensive, each plenum about US$40, these extend the length of the Airtube and are a better solution to more plenum volume ( LARGE AT 35 cc ) without losing too much Airtube Volume ...Get them while they are hot : https://www.facebook.com/Jacques72/posts/1455687521305594?hc_location=ufi

 

[jarmstrong]

 

[Sonnycruz]

Lee doesn't make plenum anymore, he messaged me back. I emailed Xtreme, so waiting for a response. Hopefully he can get me one quick. I imagine with plenum extension and my huma set to 140 I'd get the numbers im looking for. Airguns of arizona test fired rifle before I bought and its a shooter accuracy wise. Its one of my favorites now, would just like more power on tap. Even shoots NSA 29gr slugs well at 780fps. I imagine they'd be even better with another 100fps. If you have an extra plenum extension I'll take it off your hands.

 

[Sonnycruz]

Jaques from xtreme got a hold of me today, and sent out one of his plenums. I can't wait! I mainly shoot 26gr Hades and right now with huma set to 150 and hs cranked in i can get them to sound 840. It shoots the nsa 29gr slugs pretty well but speed is only at 780. Hoping with plenum and reg at 130 I can dramatically increase the speed and efficiency. Thank you for the recommendations.

 

[MBG]

Jaques from xtreme got a hold of me today, and sent out one of his plenums. I can't wait! I mainly shoot 26gr Hades and right now with huma set to 150 and hs cranked in i can get them to sound 840. It shoots the nsa 29gr slugs pretty well but speed is only at 780. Hoping with plenum and reg at 130 I can dramatically increase the speed and efficiency. Thank you for the recommendations.

Let us know how it goes, I have my three on the way to try in 177,22 and .25

 

[Sonnycruz]

I definitely will. He said it shouldn't take to long to get to me. I'm pretty excited to get it. I love the gun and its size, little more power and she'll be perfect.

 

[Sonnycruz]

Plenum came in today, shipped out on 21st so that's pretty quick from South Africa. Had an issue with oring blowing out, the one supplied with plenum but reinstalled plenum using vice to really crank it on. Works perfect, no leaks. Have huma set at 140 and hs turned in about 1 1/2 from flush. Its shooting 26.54 hades at 860 accurately , consistently and flat out from 20-50 yards which is as far as I can shoot at the moment. Sounds alot better and seems alot more efficient. So far I'm happy. I can get it over 880 easily with hs but she likes it around 860.

 

[MBG]

Great to hear,sounds like the sweet spot you needed for .25

 

[Sonnycruz]

Yes, I was close with factory but it wasn't efficient and everything was maxed out. Plenum gave alot more power but accuracy was suffering a little. Now things are perfect with minimal settings. Maybe if I changed barrel I could utilize the power more but I'm happy where its at. Shoots the nsa .29 slugs great too. Thank you guys for all the help and advice

 

[Yo]

If yours is already in the 40-42fpe power level then I suggest trying the 23gr NSA and 22 Varmint Knockers to shoot between 900 and 930fps for 100 yard shooting if your barrel likes them and shoot well in your gun before doing anything else or adding a plenum. If your gun likes the 21gr H&N Baracuda pointed they may be good enough for 100 yards as well.

 

[Sonnycruz]

I'll pick up a box of 23gr today and try them out. The 29s are just a little over 800fps but i havent tried them out to distance. They may have a loopy trajectory. 

 

[Vetmx]

Plenum came in today, shipped out on 21st so that's pretty quick from South Africa. Had an issue with oring blowing out, the one supplied with plenum but reinstalled plenum using vice to really crank it on. Works perfect, no leaks. Have huma set at 140 and hs turned in about 1 1/2 from flush. Its shooting 26.54 hades at 860 accurately , consistently and flat out from 20-50 yards which is as far as I can shoot at the moment. Sounds alot better and seems alot more efficient. So far I'm happy. I can get it over 880 easily with hs but she likes it around 860.

Using a vice to really crank it on is not a good thing with PCP’s. You shouldn’t have to do that. Everything on an air tube should just be snug at the most. I wonder what the issue is.

 

[Sonnycruz]

I spoke with Jaque about it and some block adapters have a little bevel and some do not, the ones that do need that bevel to be machined off. Mine had bevel. I wasn't aware it needed to be removed, thats what was causing oring not to seal right. It works fine now with no leaks, but its on there tight. Knowing that I was unaware Jaque is sending me new plenum with block adapter. Awesome customer service, he offered, i didn't ask.

 

[Sonnycruz]

I spoke with Jaque about it and some block adapters have a little bevel and some do not, the ones that do need that bevel to be machined off. Mine had bevel. I wasn't aware it needed to be removed, thats what was causing oring not to seal right. It works fine now with no leaks, but its on there tight. Knowing that I was unaware Jaque is sending me new plenum with block adapter. Awesome customer service, he offered, i didn't ask.

 

[Sonnycruz]