Power Plenum on .25 cal., 600mm slug liner and 33.5gr NS slug

Nope. No mods. It came from SPAW. I ordered on 1/6/20 and received it on 2/20. I remember now after looking at the pic my exact order of the slug strings. 
1583030226_7552658045e5b1fd215eb49.34011438_72CDC510-9D26-4ED9-B680-BDB9C364471C.jpeg
It actually tightened up as I shot. I need to test more.
 
Nice shot string.

I may be wrong but I think this shows you are seeing similar results. Your 700mm barrel will likley be giving you an additional 50 to 60fps over PB's 600mm barrel.


Is that not modified by SPAW? Just curious.

I don’t think so. I did not ask him to nor did I pay extra for him to.

Looks good then. Keep us updated. 
 
Nice shot string.

I may be wrong but I think this shows you are seeing similar results. Your 700mm barrel will likley be giving you an additional 50 to 60fps over PB's 600mm barrel.


Is that not modified by SPAW? Just curious.

I don’t think so. I did not ask him to nor did I pay extra for him to.

Looks good then. Keep us updated.

So you started to believe St Thomas ?
 
They are compared to what is available but I love them. At 980fps/ 3.25" scope height (eagle vision) 25/60 yard zero im only seeing a 6" drop at 100yards, thats a half inch less than strelok predicts with BC input of 0.96.

Still has around 50ft/lb retained energy at that distance, cant see a reason to go heavier....

6 inches drop at 100 yards is fantastic.
 
The Impact is the most adjustable, but can also the most tricky airgun to tune properly. The balance between the regulator, valve and hammer do not operate like most other regulated airguns. Sometimes less is more. 

@powerbroker no offense, but people like you are probably the reason why FXUSA doesn't sell the power plenum kit to just anyone. They want a certified technician to perform the upgrade.

PK

I Have no problem on offensive accusation but be sure you can defend your accusation. Do you have the pp? Can you walk the talk or your are just passing the gossip? 
the impact is not rockets science. 
Moreover, only US companies require the buyer to have it installed by US companies. In EU, they say you can install it because it is not a rocket science and they encourage to do it your own. 
So, your accusation is baseless.

I'm not saying you're not capable as you come off as quite competent. FXUSA wants it to be installed by a certified technician to ensure it meets their numbers. Probably because the Impact is not as easy to tune as some might believe. More is not always more; bigger plenum, heavier hammer or spring, higher regulator pressure doesn't always equate to more power. The Impact is a balancing act and sometimes less is more. Just saying!
 
The Impact is the most adjustable, but can also the most tricky airgun to tune properly. The balance between the regulator, valve and hammer do not operate like most other regulated airguns. Sometimes less is more. 

@powerbroker no offense, but people like you are probably the reason why FXUSA doesn't sell the power plenum kit to just anyone. They want a certified technician to perform the upgrade.

PK

I Have no problem on offensive accusation but be sure you can defend your accusation. Do you have the pp? Can you walk the talk or your are just passing the gossip? 
the impact is not rockets science. 
Moreover, only US companies require the buyer to have it installed by US companies. In EU, they say you can install it because it is not a rocket science and they encourage to do it your own. 
So, your accusation is baseless.

I'm not saying you're not capable as you come off as quite competent. FXUSA wants it to be installed by a certified technician to ensure it meets their numbers. Probably because the Impact is not as easy to tune as some might believe. More is not always more; bigger plenum, heavier hammer or spring, higher regulator pressure doesn't always equate to more power. The Impact is a balancing act and sometimes less is more. Just saying!

I stand corrected. 
 
Interesting conversation.

I can understand everyone's beef/frustration here. I do have a bone to pick with FX. But let me say I really like the Impact and the potential that it brings to the field.

Having said that I find it very frustrating that FX makes changes and doesn't mention it. I understand that they are continually trying to improve things so that's good; but it winds up some of us are not getting what "the YouTube guys" are getting and we wonder why.

Take for instance their MK2 Impact w/PP. The first few that were manufactured HAD the 57 mm HS. Then they went to the shorter less powerful spring because it was too difficult getting the speed slowed down into the sub 900 fps range where JSB MKII pellets like to live. OK, I get that but if you're going for more power with the PP isn't the likelihood you'll be shooting slugs where you want that extra speed? Couldn't FX simply toss a 57 mm spring in the box for that vary reason. Those springs, in the amount FX buys them at, shouldn't cost the company more than a few cents each. But now I have to order one and pay for shipping and wait several days if I want to explore the full potential. Very frustrating, indeed. Toss in a spring and watch their Customer Service phone call drop substantially, so FX wins as well!

My Kalibrgun Cricket included a second, less powerful spring in the box....I've never used it but it's cool they thought to do that.

Another example.......I have a Gen.1 Impact that I recently rebuilt. The older Ernest Disassembly Video shows him loosening the tiny grub screw on the hammer stop with a 1mm allen. That's a near impossible size to find in the US. So I ordered it from England and with shipping paid over 13 bucks. And guess what, it didn't fit.......they changed the grub screw on the later Gen.1's to 0.9 mm.. A 0.9 mm IS easy to find in this country; I got a Wiha set for 3 bucks on Amazon. 

FX needs to post some kind of spec sheet on their FAQ area with these kind of changes...I mean they do want us to work on our own guns with the Masterclass releases, right?

I don't know if my new MK2 will acheive the 920+ velocities I'm going to want. I'm having a clipping issue so shots are going all over the place. Once I get that resolved I'll get onto tuning. Meantime the rebuilt Gen.1 is shooting JSB Heavies at 870 fps, Lights Out! Tack Driver!