FX Impact tuning video link
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Nice! Masterclass is back...what ever happened with the old magazine tuning video?
Tip: get cheap pellets or use the ones that suck on accuracy, until you get the right speed, you will spend a lot of pellets tuning!
For example, when I tune for 0.22 slugs I use monsters or beasts, cheaper than slugs for tuning, heavy weight.
Tip: get cheap pellets or use the ones that suck on accuracy, until you get the right speed, you will spend a lot of pellets tuning!
For example, when I tune for 0.22 slugs I use monsters or beasts, cheaper than slugs for tuning, heavy weight.
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Nice! Masterclass is back...what ever happened with the old magazine tuning video?
Tip: get cheap pellets or use the ones that suck on accuracy, until you get the right speed, you will spend a lot of pellets tuning!
For example, when I tune for 0.22 slugs I use monsters or beasts, cheaper than slugs for tuning, heavy weight.
Hi Edosan, to get the most accurate speed use the actual pellet or slug you are using for comp/hunting, all ammo have different measurements and weight so there ES are different. For plinking I use the pellet that wasn’t accurate.
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Once the max velocity for the regulator setting is found, is there any difference between using the hammer spring adjuster or the valve stop to dial in the final velocity? Does using the valve stop do a better job of keeping the first cold shot after sitting overnight in a tighter es?
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Yes combination of the HSTA preload and valve stop set the final velocity. It’s normal for the 1st shot to be a little slower after idle awhile or next morning if there’s no more then 5b regulator Creep. At time the orings that seals the regulator takes a set/greater sealing surface force on the piston thats been idle for a long time so 1st shot is the break the reg piston loose and shooting/cycling the regulator makes it more consistent. There are time you can shorten the 1st shot being to low by increasing the regulator pressure and HSTA and have the VA to lower the speed. At times changing the oring inside the reg body that seals the piston and the oring on the piston Reduce the spread of the low 1st shot. Also polishing the valve rod oring sealing surface helps also. At Fx we do all the above if the gun doesn’t pass the low 1st shot test — must be within the normal ES spread— like the ES lowest speed was 890fps and ES in one mag was 10fps so the low 1st shot has to be around 880fps.
After working on AG’s off a type into 1K+ Kinda normal to see 1st shot 10-20fps low after days of idle time.
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Nice! Masterclass is back...what ever happened with the old magazine tuning video?
Tip: get cheap pellets or use the ones that suck on accuracy, until you get the right speed, you will spend a lot of pellets tuning!
For example, when I tune for 0.22 slugs I use monsters or beasts, cheaper than slugs for tuning, heavy weight.
Hi Edosan, to get the most accurate speed use the actual pellet or slug you are using for comp/hunting, all ammo have different measurements and weight so there ES are different. For plinking I use the pellet that wasn’t accurate.
I mix them, meaning I shoot for example for 30gn slug a couple, then a couple of pellets (beast), and check the fps difference, then I start speed tuning with only pellets, when I get the right speed, I check with slugs and usually all good. But when I start tuning accuracy, only like you said. So far has been pretty good.
I did that yesterday, today I went to the range and nail several 5 shot groups @ 150m with 30gn slugs 1.5 inches. Was fun! Beside me was a 308 powder and I did better than him!
(Hate that gun, makes me jump on every shot! 
)Ps: I have try both ways, did not notice much difference
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Great video. Finally I can understand how to incorporate the VA.
I guess my question is how do you know what "target speed" you need for a certain pellet to even begin to tune around?. I'm using a .25 Impact with JSM Heavy MKII 34 gn. Is 860 fps a preferred speed or as some like, 900 fps?
It would be great to have some sort of speed guideline for some popular styles. But that might be ignorant thinking.
KP
I guess my question is how do you know what "target speed" you need for a certain pellet to even begin to tune around?. I'm using a .25 Impact with JSM Heavy MKII 34 gn. Is 860 fps a preferred speed or as some like, 900 fps?
It would be great to have some sort of speed guideline for some popular styles. But that might be ignorant thinking.
KP
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Accuracy is more important than velocity.
First decide if a high shot count is important to you. If it is, then tune for the lower end like 830. If you want or need more energy and a high shot count doesn't matter, then go up from there.
850fps was very accurate for me with the 34gr MKII pellets.
First decide if a high shot count is important to you. If it is, then tune for the lower end like 830. If you want or need more energy and a high shot count doesn't matter, then go up from there.
850fps was very accurate for me with the 34gr MKII pellets.
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Bob_O,
I re-tuned my .25 Impact this weekend according to Ernest's video and your velocity suggestion and I found it's worked really well for me. I re-tuned down from 145 bar where i was getting 900 fps down to 135 bar to 850 fps with the MKII's. I set the regulator/HST combo to give me 875 fps and then dropped it down to 850 with the Valve Adjuster. On the last valve knob turn I heard the gun really get quiet.
It was very windy this weekend, (as have been the last 6 weekends), but I was able to shoot sub MOA groups averaging around 0.45" at 50 y. One group was 0.377"
I've shot great groups before but I should emphasize that the groups were very consistent. Before it was one good group in a group of so-so groups. Now, there's a noticeable lack of fliers................. now the fliers are all me!
As I was packing up to go in, I noticed a ground hog in the newly planted garden and took him out at 43 y with a head shot! A little icing on the cake, if you will!
I would urge everyone with an Impact to check out this video. BIG improvement!
Thanks again Bob_O
Cheers,
KP
I re-tuned my .25 Impact this weekend according to Ernest's video and your velocity suggestion and I found it's worked really well for me. I re-tuned down from 145 bar where i was getting 900 fps down to 135 bar to 850 fps with the MKII's. I set the regulator/HST combo to give me 875 fps and then dropped it down to 850 with the Valve Adjuster. On the last valve knob turn I heard the gun really get quiet.
It was very windy this weekend, (as have been the last 6 weekends), but I was able to shoot sub MOA groups averaging around 0.45" at 50 y. One group was 0.377"
I've shot great groups before but I should emphasize that the groups were very consistent. Before it was one good group in a group of so-so groups. Now, there's a noticeable lack of fliers................. now the fliers are all me!
As I was packing up to go in, I noticed a ground hog in the newly planted garden and took him out at 43 y with a head shot! A little icing on the cake, if you will!
I would urge everyone with an Impact to check out this video. BIG improvement!
Thanks again Bob_O
Cheers,
KP
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Nice KP!
Yes, the valve adjuster is what gives the Impact the edge over the Crown in tuning. It's amazing how quiet and smoother the shot is when you drop the last 20fps or so by closing the valve.
Yes, the valve adjuster is what gives the Impact the edge over the Crown in tuning. It's amazing how quiet and smoother the shot is when you drop the last 20fps or so by closing the valve.
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