What kind of power can i expect from the stock Impact mk2 with power plenum?

[cowabunka]

Looking to upgrade and am spoiled for choice.

Ultimately, I want to cast my own slugs (.25 47gr https://www.mp-molds.com/product/635-mm-air-rifle-pellet-8-cav-mold/) and looking to have it down range at around the low 900fps

Will the stock 600mm mk2 with power plenum be able to do that straight from the factory? what about the 700mm?

Currently i'm toying with a dreamline compact. I understand that by adding the dreamline plenum and longer barrel, i may be able to get to like 80% of where i need to be. But that kind of defeat the purpose of having a compact.

 

[sonny]

Im shooting .25 cal JSB 34gr 910fps with reg set @ 125 bar after backing off the hammer spring and valve stop to slow them down 25-30 fps and still getting 60 to 70 shots on reg depending on fill. Loving it!

MK2 600mm original S/T barrel

 

[ImpactX]

No way you're gonna push a heavy 47gr at 900. Why not go for 30 cal if you want to push closed to a 50gr slug at 900 fps. Mine is pushing 33gr nsa slug at 930 fps with a 600mm slug line. And its pushing a 36 gr nsa slug at 890-900 fps. So I find it hard to believe it will push a 47 gr .25 cal slug at 900 fps. 

 

[airgunmike56]

Wow, OK Whats the deal you guys trying to talk me into a Impact. The stats on the MK II are looking pretty good with the heavy lead .

I feel the pull of the power ..... But have they got the O ring problem fixed ?

Mike

 

[Raden1942]

I push 47 grain casts out of my airforce condor up to 1150 fps and it's totally stock. Granted it is more difficult to get a regulater to work due to lop and its a single shot instead of a multi shot but buddy this thing rips. I also don't need a reg it's plenty accurate on its own. 

 

[weatherby]

No way you're gonna push a heavy 47gr at 900. Why not go for 30 cal if you want to push closed to a 50gr slug at 900 fps. Mine is pushing 33gr nsa slug at 930 fps with a 600mm slug line. And its pushing a 36 gr nsa slug at 890-900 fps. So I find it hard to believe it will push a 47 gr .25 cal slug at 900 fps.

My buddy slings 48.5gn. 25cal nsa's with 288m/s (960fps) in his PP Impact with 700mm barrel......

No accuracy testing done, but the power sure is there. 

 

[sonny]

Wow, OK Whats the deal you guys trying to talk me into a Impact. The stats on the MK II are looking pretty good with the heavy lead .

I feel the pull of the power ..... But have they got the O ring problem fixed ?

Mike



never needed to replace a oring on mine in over 3 years

 

[Glem.Chally]

No way you're gonna push a heavy 47gr at 900. Why not go for 30 cal if you want to push closed to a 50gr slug at 900 fps. Mine is pushing 33gr nsa slug at 930 fps with a 600mm slug line. And its pushing a 36 gr nsa slug at 890-900 fps. So I find it hard to believe it will push a 47 gr .25 cal slug at 900 fps.

I can get the slugs the OP mentions at 960-970 with the polish plenum. (100fpe) 700mm barrel. 

They will need to be sized.

 

[Mrshosted]

You should expect 84.55 fpe. I dont fully understand your question. Are you asking about your dreamline or a new Impact? IMHO both guns can push the slug your asking about, but not at factory setting. It's going to require some tunning and testing done on your part. You may have your regulator set very high and have limited shoot count.

 

[DShepard]

My Impact Power Plenum is pushing the 33.95 MKII at 960 with a 140 bar reg. There is plenty of power available. 

 

[spyde82]

My Impact Power Plenum is pushing the 33.95 MKII at 960 with a 140 bar reg. There is plenty of power available. 


did you change the spring??



i am shooting the .22 25.6gr slugs at 1000fps at 130 bar reg. But had to change the hammer spring

 

[DShepard]

Only upped the reg pressure and tightened the hammer spring. You can watch the video of the tune here.



https://youtu.be/KDvuMwjwk9M

 

[Bushwackert]

No way you're gonna push a heavy 47gr at 900. Why not go for 30 cal if you want to push closed to a 50gr slug at 900 fps. Mine is pushing 33gr nsa slug at 930 fps with a 600mm slug line. And its pushing a 36 gr nsa slug at 890-900 fps. So I find it hard to believe it will push a 47 gr .25 cal slug at 900 fps.

My buddy slings 48.5gn. 25cal nsa's with 288m/s (960fps) in his PP Impact with 700mm barrel......

No accuracy testing done, but the power sure is there.

Thats actually with the slug the OP mentions, so a .25 48.5gr cast slug from the MP Mold. Reg pressure was 170 bar and I did use the old heavier hammer, old longer hammer spring and no valve return spring so not entirely stock

 

[cowabunka]

Only upped the reg pressure and tightened the hammer spring. You can watch the video of the tune here.





https://youtu.be/KDvuMwjwk9M

700mm barrel I presume?

and no mod at all? not even elongating the transfer port and pellet probe?

 

[cowabunka]

No way you're gonna push a heavy 47gr at 900. Why not go for 30 cal if you want to push closed to a 50gr slug at 900 fps. Mine is pushing 33gr nsa slug at 930 fps with a 600mm slug line. And its pushing a 36 gr nsa slug at 890-900 fps. So I find it hard to believe it will push a 47 gr .25 cal slug at 900 fps.

mainly because my goal is to cast and shoot my own slugs.
I enjoy casting, it is almost therapeutic, nothing to do with cost what so ever.
I mean, we are talking impact dollar here

 

[DShepard]

No mods, only tuning. 700 mm barrel.

 

[weatherby]

No way you're gonna push a heavy 47gr at 900. Why not go for 30 cal if you want to push closed to a 50gr slug at 900 fps. Mine is pushing 33gr nsa slug at 930 fps with a 600mm slug line. And its pushing a 36 gr nsa slug at 890-900 fps. So I find it hard to believe it will push a 47 gr .25 cal slug at 900 fps.

My buddy slings 48.5gn. 25cal nsa's with 288m/s (960fps) in his PP Impact with 700mm barrel......

No accuracy testing done, but the power sure is there.

Thats actually with the slug the OP mentions, so a .25 48.5gr cast slug from the MP Mold. Reg pressure was 170 bar and I did use the old heavier hammer, old longer hammer spring and no valve return spring so not entirely stock

Oww, he asked about "stock form" indeed

What a dirty word, "stock".... Ugh  

 

[sniperlabyo]

Looking to upgrade and am spoiled for choice.

Ultimately, I want to cast my own slugs (.25 47gr https://www.mp-molds.com/product/635-mm-air-rifle-pellet-8-cav-mold/) and looking to have it down range at around the low 900fps

Will the stock 600mm mk2 with power plenum be able to do that straight from the factory? what about the 700mm?

Currently i'm toying with a dreamline compact. I understand that by adding the dreamline plenum and longer barrel, i may be able to get to like 80% of where i need to be. But that kind of defeat the purpose of having a compact.

What you can expect from a stock .25 cal 700mm with power plenum at 160b with all adjustment at max: 

1. 38.5gn slug 960fps

2. 36.2gn slug 975fps

3. 33.2gn slug 1000fps

4. 29gn slug 1040fps

5. 26gn slug 1070fps

6. 33.9gn pellet 1000fps



your speed my very with each impact have different tolerance. 52mm or 57mm hammer spring or 16mm or 18mm HSTA



Ernest

 

[Roachcreek]

What is the max length projectile the 25 impact magazine will function with.



Regards, 



Roachcreek

 

[cowabunka]

Looking to upgrade and am spoiled for choice.

Ultimately, I want to cast my own slugs (.25 47gr https://www.mp-molds.com/product/635-mm-air-rifle-pellet-8-cav-mold/) and looking to have it down range at around the low 900fps

Will the stock 600mm mk2 with power plenum be able to do that straight from the factory? what about the 700mm?

Currently i'm toying with a dreamline compact. I understand that by adding the dreamline plenum and longer barrel, i may be able to get to like 80% of where i need to be. But that kind of defeat the purpose of having a compact.

What you can expect from a stock .25 cal 700mm with power plenum at 160b with all adjustment at max: 

1. 38.5gn slug 960fps

2. 36.2gn slug 975fps

3. 33.2gn slug 1000fps

4. 29gn slug 1040fps

5. 26gn slug 1070fps

6. 33.9gn pellet 1000fps



your speed my very with each impact have different tolerance. 52mm or 57mm hammer spring or 16mm or 18mm HSTA



Ernest

thanks! exactly what i needed!