velocity anomaly

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Craig E.

velocity anomaly

Post by Craig E. »

Perhaps someone can advise as to why groups get tighter and accuracy more consistent with cutting back on the velocity with my LP1. All other things equal, this setup seems to work better for me. I would have thought that higher speeds made for more elite results...but I will take what works best. Don't have time to keep fooling around with nuances that only frustrate.
Just curious if anyone else has noticed the same phenomenon. TIA, Craig

alance2002-at-yahoo.com.42000.0
TCK

Re: velocity anomaly

Post by TCK »

There has been one old saying in shooting that the higher the speed, the strighter the ballistic. I personally do not think this rule applies in AP shooting.
Since the range is just app. 10 m and if the pellets travels at 150 m/sec (a moderate speed for AP), it will takes less than 0.002 sec to go through the barrel and 0.65 sec to reach the target. Base on this principle, I believe velocity (speed factor) is not the major issue hee.
However, just like long range bullseye shooting guys that handloads. The combination of different kind of pellets weight, diameter and pellet velocity will results in groupings of different sizes, which may be the results of internal metal vibration, rifling and pellet shape. I remember soemone said that it is just like a frequency table, an AP will have an one hole grouping with a particular speed (e.g. 135m/sec) and grouping will widen by chaging this velocity, however, the grouping will get tighten again when another perfect point is reached, (e.g. 148m/sec).
It is not astonished to learnt that world class AP shooter will buy a large quantity of pellets of the same batch and then test for its grouping and fine tune their AP for that batch of pellets. Of course at theri level, a 9.9 and a 10.0 makes a lot of difference.


If you are really keen on AP,
.42004.42000
TCK

Some correction

Post by TCK »

The time for the pellet ot reach the target for AP in my example should be app. 0.065 sec but not 0.66sec.

.42005.42004
Craig E.

Re: velocity anomaly

Post by Craig E. »

TCK,
Thanks for the input. I am using 4.5 Vogel Match (yellow). Worked extremely well in the IZH 46 which the CO2 LP1 replaces...should say supplements. Obviously, the velocity for the 46 is generally slow compared to pre-charged pistols. Into AP? I guess you could say that. As for the 9.9v 10, that's the objective. I hesitate to mess with the trigger on the LP1,but I seem to like the more travel in 1st stage that the 46 has. I will work some more with it this way to ingrain the feeling. I gather it is what some would call a rolling trigger more than 2 stage. There is a very slight 1st stage and not too much after that ....bang. Sometimes that causes the flyer I hate, but on the otherhand, when the stars (and sights) line up right....the feeling is superb. Again, thanks for your information. I appreciate the knowledge that one can glean here. Craig


: There has been one old saying in shooting that the higher the speed, the strighter the ballistic. I personally do not think this rule applies in AP shooting.
: Since the range is just app. 10 m and if the pellets travels at 150 m/sec (a moderate speed for AP), it will takes less than 0.002 sec to go through the barrel and 0.65 sec to reach the target. Base on this principle, I believe velocity (speed factor) is not the major issue hee.
: However, just like long range bullseye shooting guys that handloads. The combination of different kind of pellets weight, diameter and pellet velocity will results in groupings of different sizes, which may be the results of internal metal vibration, rifling and pellet shape. I remember soemone said that it is just like a frequency table, an AP will have an one hole grouping with a particular speed (e.g. 135m/sec) and grouping will widen by chaging this velocity, however, the grouping will get tighten again when another perfect point is reached, (e.g. 148m/sec).
: It is not astonished to learnt that world class AP shooter will buy a large quantity of pellets of the same batch and then test for its grouping and fine tune their AP for that batch of pellets. Of course at theri level, a 9.9 and a 10.0 makes a lot of difference.

:
: If you are really keen on AP,

alance2002-at-yahoo.com.42006.42004
Joe G.

where I'm at....

Post by Joe G. »

Hi Craig, currently I am running my LP-1 at 520fps with H&N Match Hi-speeds and am quite happy with the results. Have you chrono's your LP-1?, just curious as to where it was/is at. If you are running hot there may be a light amount of muzzle flip although with your forward mounted counterweight that is probably not a factor. I have my SAM K11 shooting in the mid 400 range and it works fine for me as does my own original IZH which like yours should be in the low 400's. Next time we get together we can work on that trigger if you like. Hope all is well, Joe G.


Josephjfg-at-aol.com.42015.42000
Craig E.

Re: where I'm at....

Post by Craig E. »

: Hi Craig, currently I am running my LP-1 at 520fps with H&N Match Hi-speeds and am quite happy with the results. Have you chrono's your LP-1?, just curious as to where it was/is at. If you are running hot there may be a light amount of muzzle flip although with your forward mounted counterweight that is probably not a factor. I have my SAM K11 shooting in the mid 400 range and it works fine for me as does my own original IZH which like yours should be in the low 400's. Next time we get together we can work on that trigger if you like. Hope all is well, Joe G.
Thanks Joe. Will take you up on the trigger thing. No to the chrono. No access. I can only judge by the pellet penetration in the trap per internet table (Ian Pellant I think). Look forward to seeing you soon. Good luck at DC or Delran.
alance2002-at-yahoo.com.42034.42015
Barry

Re: where I'm at....

Post by Barry »

Craig, If you'd like to run your LP-1 over some screens to see what effect changes in FPS have, let me know. I have a chronograph that real portable and easy to set up. I could drop if off sometime and your welcome to play with it for awhile.




: : Hi Craig, currently I am running my LP-1 at 520fps with H&N Match Hi-speeds and am quite happy with the results. Have you chrono's your LP-1?, just curious as to where it was/is at. If you are running hot there may be a light amount of muzzle flip although with your forward mounted counterweight that is probably not a factor. I have my SAM K11 shooting in the mid 400 range and it works fine for me as does my own original IZH which like yours should be in the low 400's. Next time we get together we can work on that trigger if you like. Hope all is well, Joe G.
: Thanks Joe. Will take you up on the trigger thing. No to the chrono. No access. I can only judge by the pellet penetration in the trap per internet table (Ian Pellant I think). Look forward to seeing you soon. Good luck at DC or Delran.

.42067.42034
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