With the multiple subsonic calibres I use myself & for customers I suggest zeroing at 75 yards, it will be approx 1-1.5" high at 25 & 50 then 6-6.5" low at 100, you really need to check itQuote:
Originally Posted by kingscoatkiwi
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With the multiple subsonic calibres I use myself & for customers I suggest zeroing at 75 yards, it will be approx 1-1.5" high at 25 & 50 then 6-6.5" low at 100, you really need to check itQuote:
Originally Posted by kingscoatkiwi
See chart above...go onto huntingnut.find pointblank online in box top left of main page.poke in your numbers and see what you think. Sure beats guestimate. ....pretty close to what kiwi Greg just said at same time.Quote:
Originally Posted by kingscoatkiwi
We have forgotten a lot about shooting using .22 velocity or slower rounds, and I blame our facination with optics. Open sighted rifles used to have rear sights graduated often out to several hundred yards and it was a simple matter of adjusting the rear slider to suit. Of course you had to get good at estimating range which is also a bit of a lost art. I'm a firm believer in teaching people to use irons I think it teaches you a lot about ballistics and just helps you be a better shooter when or if you move to optics
My 22 is doing about that speed and the scope is only a little under 2 inchs from the bore. It passes throught he 50m mark on the way up, and again at about 65m then is rather low at 100m. I would have thought a 175gr doing the same muzzle velocity would be able to maintain a little more momentum and thus slightly better speed down range. I certainly dont have my scope that high on my 22.Quote:
Originally Posted by Shearer
Being a 30/30, there is every chance the OPs rifle is open sighted, putting the sighting plane much closer to the bore axis.Quote:
Originally Posted by timattalon
Oh alright....hold the line caller.shall I stick in 170 GRN too??? And proper BC while I'm at it....
So with all four scenarios... Drop at hundy is still significant.... Out to sixty....very manageable indeed.past that it gets problematic and if you guess too short it goes sideways quickly.
All good.Quote:
Originally Posted by Micky Duck
I dont think diffferent weights will have much impact under 100m if the muzzle velocity is all about the 1050fps. I think the heavier weights will maintain a little more momentum and could be a few fps faster than the 22LR at 100m but not enough to make any real world difference at that range.....
. I was thinking more of moving the zero point so where the procjectile passes through on the way up is closer to the 50 or 60m mark rather than the 20m mark even if it just peaks at or over that zero rather than higher. It will still fall drasticly, the same as my 303 with a 215RN does at 300. (2050fps at muzzle...zero at 50m 2" high at 100m, zero again at about 130 and falls like a stone to 38" low at 300m....)
Practially your trajectory above of peaking at 40m (ish) is about as practical as it needs to be. Anywhere from the muzzle to about 75m will be within a 6" circle if you aim at the centre of that circle,and that would be more than adequate for deer. I would be more likely to zero it at 75m as per your later image. It will be 2" high at about 50m which is still in that 6" diameter circle and at 100m you will be about an inch below. If you were to aim at the vitals on a deer sized target that is about a 10" dinner plate sized circle, you will still be in the vitals at 100m. And if you are not sure if it is 75m or 100m but estimation, aim a few inches above the centre of that circle and the margin of error is still within the lethal zone.
That last paragraph is not aimed at you Micky Duck, more at anyone else who may not quite get what I am trying to convey.
Most of my 308 subs i need to aim about 8"/200mm high at 100m with a 50m zero. But yeah as others said, will need to aim higher. My 308 subs range form 150gr to 210gr
@timattalon unfortunately you can't get a subsonic to first cross line of sight at fifty yards on way up....if you look at first picture it will be more obvious.its dropping too fast to do it.... Zeroed for fifty might just about skim along just above line of sight but will drop immediately past fifty.... Rainbow trajectory.
That’s what I was trying to point out when I mentioned the probability of open sights. Rather than aiming it at you Micky Duck, I was pointing out that a lower sight axis, relative to bore axis, results in less ‘mortar effect’.Quote:
Originally Posted by Micky Duck
Attachment 279353 as requested...in order to hit going upwards at fifty yards.....take note of height of scope above bore. Having had this set up on .303 Brit years ago....right pain in arse with supers as always hitting too high or too low.
