I shoot between 50-300 yards. I shooting a cz457 pro varmint with sk standard plus ammo. I have tried the custom drag curves, dsf, and tweaking bc but cant seem to get my data to line up. If I get it to line up 50-150 its off past 170 yards. If I adjust it to line up 170+ then it is off inside of 150. Is there a trick that I dont know about other that having 2 different profiles or balistic calculators?
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I have its zeroed at 50 yards and zero height is set at 0 on kestrel.
you need to put in the height from the center of the bore to the center of the scope
Its set
Try running 2 diff b.c. one for 150 and closer then 151 and further.. bc at 300 should be around .135ish
If that doesn't work try a velocity calibration for the further distance. If that works let me know, i will send you a bill/ invoice.. lol just kidding
Im running .131 bc right now. Ill try and see if mv calibration does
Cool,keep me posted!
I’ve been using 1060 fps and .170 BC on a 16” 457 and standard plus. Just a generic calculator in about 45* weather and this has been real close out to 175 for me. Also very close in the wife’s RAR with 20” barrel.
Have the temps been the basically the same during testing? It seems to me that standard plus can be pretty sensitive in my experience.
Have the temps been the basically the same during testing? It seems to me that standard plus can be pretty sensitive in my experience.
Do you know your actual FPS? SD? ES?
What ballistic calculator are you using? What drag function are you using? G1 seems to work best for rimfire. My BC is set at .172. I just shot a comp from 60 to 400+ and my dope was pretty much spot on over many distances.
What ballistic calculator are you using? What drag function are you using? G1 seems to work best for rimfire. My BC is set at .172. I just shot a comp from 60 to 400+ and my dope was pretty much spot on over many distances.
Use RA4 (G5) drag it will line up better then a G1. Also G7 tends to be closer for subsonic then G1 but RA4 is best.
G1 of 0.131 is what I have for sk out to 400 yds. Using G1 you will hit high at 200 if trued to 400.
G1 of 0.131 is what I have for sk out to 400 yds. Using G1 you will hit high at 200 if trued to 400.
None of that makes any sense whatsoever. G5 is based on a bullet model with a tangent ogive and boat tail. It’s very similar to G7. Neither remotely resembles a 22LR bullet. What does? The G1 projectile.
Try it.
I created a chart of all the available drag functions in Strelok Pro. The chart was the dope from 25-500 yards in 5 yard increments. I was then able to shoot from 50 - 260+ yards confirming actual dope. The G1 lined up near perfectly. The Lapua Center X profile was next. The G1 was better and still provide hits w/o correction to elevation through all 12 stages from 60-450+ yards. I'll keep recommending G1. Not to mention I was told by a top/winning shooter to use G1 in a conversation in regards to setting up a buddy's Kestrel.
Here is some of my comparisons between G1 and G7 most apps dont have G6, G5, RA4.
Most people look at BC as relating to high velocity. With 22lr we are only interested in subsonic. The different BC curves in the subsonic region give the BCs a different shaped drop. G1 CD becomes higher faster as the velocity drops then say a G7. So when trued at say 400 yds you BC will be to low for a perfect 200 yard drop.
This also can be slightly app dependent as not all give the same info out all else being the same.
I dont just go by what others say I test for myself. 22lr ammo is fairly inconsistent so. Shoot a large group at 200 yds calculate center of group and then figure out what your BC should be based on the actual ave velocity in that group. Then go to 400 yards shoot a large group (if good ammo 20 shots min) and recalculate your BC. See what curve matches best for you. We might not end up with the same results because even PDMs vary gun to gun etc.
Just shooting steel plates out to distance to true drop is not accurate enough if your looking for exact. You can be off quite a bit and think your good. The truth is you probably are good for PRS/ NRL22X matches.
Most people look at BC as relating to high velocity. With 22lr we are only interested in subsonic. The different BC curves in the subsonic region give the BCs a different shaped drop. G1 CD becomes higher faster as the velocity drops then say a G7. So when trued at say 400 yds you BC will be to low for a perfect 200 yard drop.
This also can be slightly app dependent as not all give the same info out all else being the same.
I dont just go by what others say I test for myself. 22lr ammo is fairly inconsistent so. Shoot a large group at 200 yds calculate center of group and then figure out what your BC should be based on the actual ave velocity in that group. Then go to 400 yards shoot a large group (if good ammo 20 shots min) and recalculate your BC. See what curve matches best for you. We might not end up with the same results because even PDMs vary gun to gun etc.
Just shooting steel plates out to distance to true drop is not accurate enough if your looking for exact. You can be off quite a bit and think your good. The truth is you probably are good for PRS/ NRL22X matches.
Posted this in your inquiry on the other thread. Follow DThomas's instructions precisely. If it doesn't work something else is amiss. I wouldn't expect good results from ammunition lots not less than 30-40 ES and a SD 10 or below. https://www.snipershide.com/shooting/threads/dsf-truing-with-22-rimfire.7033373/#post-8919173
Strelok Pro gives me perfect elevation out to 500 yards with the standard model, so I won't be doing that.Try it.
Fair enough. I shoot paper to check out to 400 and that was not the case with me. I think that brings up a important point though if your looking for perfect we all have to check for ourselves.
Kestrel. 1065/ 7 sd/17 es over labradar. Bc i been using is g1 .131
This one is your .131 w/ a 2.5" scope height vs. my 1.85".
Here's RA4 using .131 but @1.85" scope height.
RA4 and G1 bc numbers will be different
Could you do one with a 50yrd zero?
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Here are 2 of my examples out of my CZ457 Pro Varmit with 16" barrel and 1.8" height... one is 1150 FPS and the other 1079. I have found using a BC around .130 or .132 works well for me. Playing with the sight height make a small difference if you are close it may move it a 1/10th here or there - if you are way off it will make a big difference.
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I need the BC you want and a scope height to get you the most accurate. Also, G1 or RA4 or both? Essentially you can just subtract .1 mil from the 25 yard zeros above.
I have chronographed my bullets at 50,100,200 and 330 yds to build a veloicty curve. I build it on my avg. ES and atmospheric conditions must be noted correctly. Often you will find it off a little , but a little at 330 is a bunch at 500 yds plus humidity bleeds veloicty quickly on rimfire projectiles due to their shape. Shoot through your screen at 50 and 100 adjust veloicty data 1st to match 50 yard screen results then run your data and compare the projected data to the actual screen results at 100. If the projected data FPS is off adjust the bullet BC , this all needs to be done on a stable day. This should get you very close do not adjust by single shot use the avg. of 5-10.
You guys are geniuses. I've never been around precision shooting, just shoot here at my house for the most part. I'm reading this thread and find that most of this is German to me. I appreciate those charts up above, it helps to study it and make some sense of it.
Why not just go out ...shoot....and record your data. Seems to many are stuck on what the damn computer says. Use that as a basic starting point, and make adjustments from there.
Because having a computer solution will allow you to not have to shoot every few yards out to 400ish and allow you to extrapolate data for different temperatures/density altitudes/ whatever else. Other wise you have to find time to shoot in every conceivable weather setting and at dozens of yard lines for each of those weather conditions. Add in wind, and you have a whole lot of data to collect just to be equal to a kestrel.
Your zero height shouldn't be 0. It should be in the 2.00" range maybe more depending on rings etc
I get that, as I use strelok for my things. But that is just a starting point. Thats like hearing the guys during deer season that their rifle is good out to xxx yards because they boresighted it at 100 yards.
You have to actually get out and spend time with your rifle at different ranges. Each rifle/barrel combo will be different no mater the make.
The computer will get you close, under extremely controlled conditions. Thats why I stated to quit relying 100% on your computer. You have a better one between your ears. Document your shots and learn it. There is no computer program that will show you how your rifle will work 100% of the time.
Was just typing something like this....
Measure your barrel diameter, divide by two.
Measure your scope bell, and divide by two.
Measure the distance between the bell and the top of the barrel.
Add these three together to get your scope height. Mine are around 1.81" or so. With a scope height of 0 you are telling the program that your scope is looking down the bore of the barrel.
For bore over sight/offset. Just measure from the center bore of the barrel chamber to the split of your rings. A tenth plus/minus will make negligible difference.
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Gas port hole on side of action to middle of wind cap
You're probably not missing because you entered the wrong scope over bore hight unless it's inches difference. And then you'll only see it at long distances. IOW, close is good enough.
He said he set it at '0'
He said impact height 0 not scope height.
Rimfire BC is not going to be affected by velocity. It’s a subsonic round.
What 2 ammo did you use?
How are you measuring BC?
ammo ive shot out to 350 in summer (new england) only required a velocity change (per chrono) to connect on soda can targets cold bore a few weeks ago woith a >30 fps change
I think lot to lot variation is the difference. I have shot several lots of the same ammo with almost identical velocity and got different BC # for long range.
I have never had to change the BC If I used actual velocity when truing. E.g. if I true at -10⁰c at 25⁰c the velocity will change but the BC will be the same.
If you changed your velocity to make the drop line up this might not work.
I have never had to change the BC If I used actual velocity when truing. E.g. if I true at -10⁰c at 25⁰c the velocity will change but the BC will be the same.
If you changed your velocity to make the drop line up this might not work.
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