I have seen 880-970 but have seen more 900-920 but not sure if that is for the original or MK II.
.25 JSB 33.95 MK II fps preference?
- Thread starter Jay308
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That’s the twist of my Ghost, it came shooting them at 950 fps, SD/ES were good and test target looked good too. So 900-920 should be ok. Kinda wanted to shoot it at 60 fpe.
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Some time ago I did a lengthy research about the speeds, both the MK1 and MK2's.
1:27 STX-A Pellet liner
Started let say about 850 fps, 5 shot groups
whenever change a speed either with a Reg or with a hammer spring, disregard a first 4-5 shots to settle the springs, don't shoot it in a ring but in a sand behind.
incrementally increase the speed by 10 fps
starting from 850-860-870-880-890- and so on to let say 950
So that would be roughly 5 shots (off the target in a sand) to set the spring and 5 shots in its own ring, to document for each speed timestamp.
You will shot let say 10 target rings 5 shot each.
With increasing the speed you can track the groups start shrinking and keep increasing the groups starts opening up and again later on shrinking.
I have found out that between 850 to 950 there were two or three speeds with tightest groups of 5 and same about two or three speeds with looser groups of 5.
This exercise will eat up at least one tin and more than a good half day of shooting and writing down the logs.
And this was just a rough 10 fps incremental steps.
If you wanna be real anal about these tests, pick your best group and start doing again -10 and increase incrementally by 2 or 3
Couple examples, the goal is not scoring but to monitor the groups change with a tune change.
Have fun
1:27 STX-A Pellet liner
Started let say about 850 fps, 5 shot groups
whenever change a speed either with a Reg or with a hammer spring, disregard a first 4-5 shots to settle the springs, don't shoot it in a ring but in a sand behind.
incrementally increase the speed by 10 fps
starting from 850-860-870-880-890- and so on to let say 950
So that would be roughly 5 shots (off the target in a sand) to set the spring and 5 shots in its own ring, to document for each speed timestamp.
You will shot let say 10 target rings 5 shot each.
With increasing the speed you can track the groups start shrinking and keep increasing the groups starts opening up and again later on shrinking.
I have found out that between 850 to 950 there were two or three speeds with tightest groups of 5 and same about two or three speeds with looser groups of 5.
This exercise will eat up at least one tin and more than a good half day of shooting and writing down the logs.
And this was just a rough 10 fps incremental steps.
If you wanna be real anal about these tests, pick your best group and start doing again -10 and increase incrementally by 2 or 3
Couple examples, the goal is not scoring but to monitor the groups change with a tune change.
Have fun
Keep reading the JTS are more consistent, I have 5 tins of the JSB. I guess I’ll weight sort them, after I put the ghost together and actually shoot them
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My P35-25 can't push them faster than low 800s and can't do that in the winter. But they are still it's most accurate pellet.
For those who find significant speed preferences, is it with FX barrels or larger diameter barrels like CZ and Walter Lothar make? My guns all have thicker barrels and none have shown a strong preference for a particular speed. My 177 can push it's favorite up well over 900 fps and I've tested a wide range without finding one velocity that was more accurate than others, for instance.
For those who find significant speed preferences, is it with FX barrels or larger diameter barrels like CZ and Walter Lothar make? My guns all have thicker barrels and none have shown a strong preference for a particular speed. My 177 can push it's favorite up well over 900 fps and I've tested a wide range without finding one velocity that was more accurate than others, for instance.
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I have always shot them at 930fps and work great in all 3 guns.
One of my favourite pellets for sure.
One of my favourite pellets for sure.
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I didn't have a lot of time/opportunity to test my .25cal ghost last year, but this one 5 shot group at just under 900fps looks promising. I think I pulled the last shot and it went high.
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Yeah, I keep reading that too, and have bought them in .22 and .30 caliber, and my guns still shoot better with JSB. Unfortunately, I was so convinced that they were obviously better, by everyone, that I bought a lot on blind faith. Don't do that, until you try them.Keep reading the JTS are more consistent, I have 5 tins of the JSB. I guess I’ll weight sort them, after I put the ghost together and actually shoot them
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Definitely good advice. They may not be the best for every individual gun out there. My daystate shoots the jts a little better. My fx shoots the jts and jsb heavies pretty much equal. I like the jts as they just look more uniform and better made.
OP’s question. Like stated earlier it is best to test at various speeds from say 850-950 to find the ultimate best for your barrel. I have never done that. I have always run them right around 900 and they are well beyond accurate enough for my needs and abilities.
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