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Can someone tell me what's changed between Friday and today. Fridays grouping of 3 shots versus today's 6 shots are substantially different. I'm thinking maybe temp and shooting position??? After @dannyb suggested testing for consistancy with speed I have this. All loading the same.
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Attachment 147682
Greetings Charliehorse,
Probably nothing at all. In a series of groups some will be smaller than the others and some larger. The first group is three shots and these are often about one third smaller than five shot groups. The second group velocity is slightly faster than the first, for some reason, but about the same ES and, discounting the last shot, roughly what you would expect. Three or five, even six shot groups will have a random dispersal of size. Some testers use the average of three, three or sometimes four shot groups to get a better measure of accuracy. It is likely that your first group was unnaturally small and the second is more representative of the rifle. Good accuracy anyway. Some would discard the second group and crow about the first but they would only be fooling themselves.
Regards Grandpamac.
Yes, what grandpamac said. If you look at shots 1, 4 and 5, they are very similar to your initial 3 shots.
Your just shooting your next phase of load development which is always measured on a bigger sample
That still quite a velocity spread for me which points to inconsistency in some way or another in your load prep, could be neck tension, seating depth, charge weight just to name a few things. I could go into these things but I'm certainly no expert.
There's nothing wrong with that grouping but yeah if you want tiny groups every little variable matters.
I like my velocity spread to be 20fps or less but then my rifle will shoot 1/3" 3 shot groups at 100 yards all day, no idea what it would do with 5 but pretty similar I imagine just dont see the point as its a hunting rifle and the first shot counts as it's usually the only one.
Something to think about too is heat soak your barrel warms up as you fire consecutive rounds through it, when I shoot groups I wait 2 minutes minumum between shots after fireing 1 fouler first....wait 2 minutes 1st shot wait 2 minutes 2nd shot wait 2 minutes 3rd shot.
Keeps the barrel at a consistent temp. Hope some of this helps.....sorry if it doesnt :thumbsup:
Appreciate any input good or bad. Was hoping to load up a swag and stash them away. I write down the av velocity and adjustment for zero so that I can pull out and shoot when ever required, but I'm in 2 minds now. Guess I'll have to load a 3rd lot and see what I get. I want to knock over small critters at longer ranges so I dont have much forgiveness on target.
Consistency is the key, shooting technique, loading variables play a huge role in this.
SD is 15 so could be better but really not too bad. I am with grandpamac on the rest ...
bush hobbit here.
stop over thinking it.
extreme spread.....doesnt even factor into equation out to say 350 yards....if you go back to what was arguably the first NZ hunting book on longish range shooting (now considered mid range) Matt n Bruce Grants SHARPSHOOTER .you will see an ES OF 50 was great going..... and before you get all hot under collar you longer range fellas...poke in figures at for "discussions " sake 750 yards...a long shot for most and then do same with 100fps LESS velocity and tell me how much you missed by.
if your squares are 1" thats a dead deer with any of those shots,although interesting your 2nd session was low n to right???change of hold maybe???
another thing that jumps out at me....why are you zeroed for hundred yards???? YES it makes fiddling n twiddling with dials easier if you dont remember to take in the bit you are zeroed for already...BUT if you are working off paper dope chart thats easy to do...just factor it in when printing it off.
IF you were to zero 2-3" high at hundred yards you can simply point n shoot out to 300ish and backline hold for another bit more again....
but Im a bush hobbit so all abit above my paygrade really.
Thanks @Micky Duck, this setup is small game only. Plovers Magpies Hares etc. Squares are half moa. Max distance will be most likely be 400m although I did try 500m the other day.
The 3 shot group was shot standing using bipod on the water tank and the 6 shot was shot in the prone position with bipod.
I'm not a bush hobbit and it's above my pay grade also. Everything I've learnt has been feiom here or the 'interwebs'
I say Charliehorse,Quote:
Originally Posted by charliehorse
That small game is going to be in even smaller pieces when you hit them with that rifle. I assume it's a .22-250.
Regards Grandpamac.
so if half inch squares...all your 2nd group of six are in roughly an inch.....thats a dead plover/bunny/magpie at that distance....out to 400,its going to open out to 4" so still very good chance of making pink mist.....
im going to take a wild guess here from what you have just posted...the standing group,you have firm grip of forend...and the prone,different grip....maybe even the "hug yourself" off hand on toe of stock?????
even if not...your loading on bipod would be diferent..I know myself if standing shooting over something I tend to lean forward to put weight on arms.... it MIGHT explain diferent point of impact.
and again if out to 400 on varmits....2" high at hundy MAY be easier .
@grandpamac you'd be spot on with the calibre, and sometimes yes theres not much left....legs and wings seem to fall off. @Micky Duck 'hug yourself' for both but you're quite right with the loading when standing. I'll need to be mindful when finalising my load. The 2" high would be easier because of point and shoot? Or something else I'm missing? Because my ranges vary from 80m to 400m I just assumed a 100m zero and dial up to whatever would be easier. It's all new to me
I will go and do some magic with figures and try to post what I mean...be clear as mud then.
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COULDNT quite get what I wanted but when you run figures and have a 225yard zero...2" high at hundred is darn close to it...means you can point n shoot on magpie with XHAIR on centre of mass and expect a hit out to about 275..... will try to get proper picture/graph to show what I mean.
Attachment 147753
care of www.huntingnut
asuming BC is indeed .467 and programme uses G1 data this will be about right
asumed 3130fps average
75grn
1.5''above bore is centre of scope
by pushing zero out to 240 yards it fits better than 225 yards.
Greetings Charliehorse,Quote:
Originally Posted by charliehorse
The neat little chart and data the Micky has furnished are based on a maximum trajectory above line of sight that will not be a miss over on deer and give a maximum point blank sighting range. Your targets are a lot smaller so you need to work out how much above line of sight you can tolerate. This is likely to be somewhere between 1 and 2 inches (25 to 50 mm). You can then use one of the free on line ballistic program's, such as the Hornady one to sort out your Zero range. Once you have put in your ballistic coefficient, velocity and sight height above bore (this last is important as it effects trajectory) select the closest spacing and say 125 metres zero range and look at the trajectory. You can fiddle with the zero range until the projectile does not go above your selected maximum trajectory above line of sight. You don't have to zero the rifle at the zero range just zero it above or below at a convenient range in line with the trajectory. This sounds a little complex bit it is easy once you have worked it through.
Regards Grandpamac.
@grandpamac you're right that does sound complicated. I'm currently using the Hornady app and it has been successful out to 350m so far. I will have a play around with it and see. I am reluctant though given my current system is working
Greetings Charliehorse,Quote:
Originally Posted by charliehorse
The good thing about playing with new ideas is that you don't have to change what you are already doing unless you can see an advantage. After all you don't need to change anything unless it works for you.
Grandpamac.
I am a convert to the point blank zero theory and mil or bdc reticles, make pb zero as long as you can then use the drop marks. I don't like twiddling dials. When using your ballistic app have a play with scope height as well the results will possibly interest you.
have ANOTHER look at the 2nd chart....assuming magpie is somewhere around 4" of verticle vital area........projectile stays within the theoreticle 4" tube out to 275 yards....Quote:
Originally Posted by grandpamac
I took into consideration what you saying thus went no more than 2" high instead of usual 3" at hundy....
