FX Impact MK2 PP 700 mm 25c transfer port
- Thread starter bigHUN
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Mine is 5,5x 6,5mm
You can go up to 7.2mm in length, then it matches the TP hole in the block
Mine is 5x7.2mm, 5.5mm is tricky IMO because of the chance your pellets/solid will catch the TP or even drop into the TP hole.
I tried several different probe designs, but the opened up & epoxy filled original one seemed to give me the tightest velocity spread.
Regarding speed, it didn't make a noticeable difference, but I have to say, I have turned the inner hole to a significantly bigger diameter as well (5mm - 5.2mm if I recall....)
The biggest advantage of the hollow probe design is that the pellet or solid is guided around the whole circumference of the pellet, and will prevent canting pellets/solids during loading.
Another advantage is that the seating depth will be just about the same for every projectile, a pin probe in combination with a diabolo type pellet will seat less deep because of the hollow skirt.
Same goes for solids with concave base.
EDIT: Caliber confusion
Now I see it is about a 25 cal. Nevermind, 5.5mm is a good width for a 25 cal. However, the rest of the story above is still valid Regards, Gijs
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weatherby:............... tried several different probe designs, but the opened up & epoxy filled original one seemed to give me the tightest velocity spread.
On my non FX 22 project gun I lowered the speed for almost 200 f/s down to 785 because I get there a max/min spread within 5 f/s, also I am indexing my pellets as well.
What did you sad? "the opened up & epoxy filled original" what that means?
On my non FX 22 project gun I lowered the speed for almost 200 f/s down to 785 because I get there a max/min spread within 5 f/s, also I am indexing my pellets as well.
What did you sad? "the opened up & epoxy filled original" what that means?
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I have found that after modifying my pellet prob in 2 impacts, the ES and SD go up. I usually can get 1 digit number ES but after modification usually the ES is at the range of 1x. I will try weatherby method using epoxy to make the turn smother.
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I am having difficulties with these english acrimonim or call whatever airgun slang
Can you help please and repeat, and talk slow
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I am having difficulties with these english acrimonim or call whatever airgun slang
Can you help please and repeat, and talk slow
Extreme spread and standard deviation, it's measured by calculating the velocity of a string of shots. Lower is better.
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I am having difficulties with these english acrimonim or call whatever airgun slang
Can you help please and repeat, and talk slow
Extreme spread and standard deviation, it's measured by calculating the velocity of a string of shots. Lower is better.
Thanks, now I understand
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Actually, what is a difference in between the " Extreme spread and standard deviation". I would assume the spread over a distance with indexed pellets, but the deviation is a measuring device uncapable of consistently calculate?
I am asking based on having several chronographs in the past (indeed for archery only) but I had a situation having several brand and model in the same time. I compared them simultaneously and they showed different values (from same brand).
Marginal error how the units sensors measure and calculates....lets take this in consideration.
Shooting arrows - or pellets, in let say 30 second sequence, within 5 minutes of measured time, same ambient temperature same air density, same indexed projectiles, ,,why is a deviation?...on any chosen brand same units or multiple units.
I ended up having this "ultrasound" - shot through hole type chronograph from aliexpress, not because I like it the most but because I got tired of spending money further (for many years again and again) on any sophisticated marketed units. This one showing me the most tightest numbers (like it or not)... I redesigned a $200 Chinese franken 22 project gun....the deviation is max/min 3 fps +/- for a best grouping @ 50M (I call this a pretty f*n amassing job I did with this f*n cheap Chinese crap. Sorry guys for my language, I just wanted to express finishing my standpoint.
Are these numbers any accurate for total deviation? I have no idea, to prove some shall spend 20-30x more $ for some heavy commercial unit.
Edit:
The problem with this chronograph unit is....it is not like changing tires on my car with buddy's and having a case of beer
I am asking based on having several chronographs in the past (indeed for archery only) but I had a situation having several brand and model in the same time. I compared them simultaneously and they showed different values (from same brand).
Marginal error how the units sensors measure and calculates....lets take this in consideration.
Shooting arrows - or pellets, in let say 30 second sequence, within 5 minutes of measured time, same ambient temperature same air density, same indexed projectiles, ,,why is a deviation?...on any chosen brand same units or multiple units.
I ended up having this "ultrasound" - shot through hole type chronograph from aliexpress, not because I like it the most but because I got tired of spending money further (for many years again and again) on any sophisticated marketed units. This one showing me the most tightest numbers (like it or not)... I redesigned a $200 Chinese franken 22 project gun....the deviation is max/min 3 fps +/- for a best grouping @ 50M (I call this a pretty f*n amassing job I did with this f*n cheap Chinese crap. Sorry guys for my language, I just wanted to express finishing my standpoint.
Are these numbers any accurate for total deviation? I have no idea, to prove some shall spend 20-30x more $ for some heavy commercial unit.
Edit:
The problem with this chronograph unit is....it is not like changing tires on my car with buddy's and having a case of beer
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Mine is 5,5x 6,5mm
You can go up to 7.2mm in length, then it matches the TP hole in the block
Mine is 5x7.2mm, 5.5mm is tricky IMO because of the chance your pellets/solid will catch the TP or even drop into the TP hole.
EDIT: Caliber confusion
Regards, Gijs
Back to OP
Looks like the new Impact MK2 PP got a new pellet probe. Since I could not find a source to have a spare fill/pellet probe I toke it out the OEM and made some measurements for planning next steps.
The shape of a "hole" is not a hole but a "V" shape looking from a side view, it was milled out from a side same setup when they machined the flat and the setscrew hole.
Now this makes me tinker, not seeing any sense increasing the 5.85 "hole" into a bigger slotted shape (as mentioned above) if this probe tube ID is only 5.15 mm (that is a limiting feature). I don't want to make an open end if that can create an issue with loading pellets/slugs into final position.
Waiting for a new brass piece with rectangular transfer port from Huma (also ordered some NBR90 orings from a local source), when all parts in my hands I will take a closer look into block what is a transfer port size there.
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As i said, it gave me 10fps alone
Spyde, I made one also but had trouble making the pin long enough to allow it to seat the pellet deep enough and still use just a single shot loader. With the pin going up inside the skirt I had to allow for that extra length which left the pin protruding slightly into the magazine slot Were you able to use a mag with your pin style?
jking
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Jking, what if you where to thread the inside of the probe. Allowing you to adjust the depth of the pin on the probe or making it tip interchangeable.
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I got some parts in for my shooting jig I designed, but the Huma parts are late, most likely after weekend somewhere next week.
The "area" in cub mm for a transfer port is limited what it is (OD 5.15 mm), we cannot make it bigger only up to a limit, or the price of the pellets/slugs jamming.
I have time and I will measure up for CAD starting from block transfer port, will see over the weekend I need couple hours quiet time. I would need that Huma square TP to see what is a limit, because yes there is it somewhere, round or square hole.
The "area" in cub mm for a transfer port is limited what it is (OD 5.15 mm), we cannot make it bigger only up to a limit, or the price of the pellets/slugs jamming.
I have time and I will measure up for CAD starting from block transfer port, will see over the weekend I need couple hours quiet time. I would need that Huma square TP to see what is a limit, because yes there is it somewhere, round or square hole.
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What is a goal? 10-15 fps? c'mon if you really need that - the solution must be somewhere else. I have a pin on my 22 (not FX) and that performance is limited to a single size/brand pellet only, or you get inconsistency on load.
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Agreed, to me its not worth the possible issues feeding/seating for such small gains. Turn the reg up 1-2 bar and it equals the mod.
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I've tried 3 different probe designs, a pin, a pin with curved shape and the original one, elongated, increased ID (0.3mm wall thickness), and filled with epoxy to steer the airflow towards the barrel Inlet.
Long story short, as far as speed goes, it doesn't make a real difference.
However, the upgraded original probe seemed to give a tighter spread than the pin probes.
I keep on using the hollow probe, it is my favorite.
Long story short, as far as speed goes, it doesn't make a real difference.
However, the upgraded original probe seemed to give a tighter spread than the pin probes.
I keep on using the hollow probe, it is my favorite.
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Would that be with an old or new power plenum? Because filling in the empty space "behind" the transfer port is actually decreasing the air volume for that 1/4 cube centimeter - or a number or molecules if you wish
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I have been told from FX that there is no new designed pellet probe in the new Impact MK2 with power plenum.
This story sounds like another rumor.
This story sounds like another rumor.
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Sorry if I made a confusion, I don't know this is a first time I have the probe in my hands, maybe it is a language only how people earlier called it "a hole".
My question was based on somebody sad earlier about a dimension "5.0x7.2 elongated", but what I see is, my probe have an opening width of 5.85 which is actually not a hole (just look like a hole) but cut-in from the side that looks like a "V" shape. Maybe it is just a perspective from which side you looking in to it, take a look the pictures taken from two angles (like a top view and front view).
Without having a brass piece in my hands I don't see a reason "elongating" or making it wider/longer because the limit is the probe-tube ID 5.15 and that is the "area" the air must go through. Midnight at my place, piece and quiet in the house, feels like a perfect time to take the Impact apart - for first time
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