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Just sighted my 30-30 with subsonics at 60 yards for my grandson to try as less recoil, he’s asked me if the animal is further than 60 yards should he aim higher or lower to which I replied “ not sure son I’ll have to ask a few guys on the intraweb thingy”
So if it’s spot on at 60 do I go higher or lower for 100?
A shit load higher at hundy.... Think 22lr. But seriously,if using them out that far,you need to put up targets and make sure your drop is right.
Wouldn’t be shooting big game at over 60m with subs..also fall like a brick at 100m ,my 308 is around 12in lower than full power load at 100m.
As per previous replies, don’t compensate vertically, get closer.
It "should be" around 7-8 inches low at 100 but as previously mentioned you have to validate it at various ranges to be certain
Yes, a surprising amount of drop as I found out many years ago. I made a fully suppressed .45/70 H&R Topper for a customer about 1975 and we took up to a quarry in the Port Hills to sight in with 500 grain subsonic loads. Zeroed it at 75 metres and then aimed at a white rock at the top of a 20-metre slip at 200 metres to see what the drop was. A sheep grazing at the bottom of the slip got a fright when the bullet impacted between its legs!
Would that also work if the trajectory paassed through the 60m mark on the way up then through (probably closer to 100m ) on the way down? I figure it would peak at about 70....maybe.Quote:
Originally Posted by Micky Duck
:thumbsup:Quote:
Originally Posted by longshot
Cheers �� ��Quote:
Originally Posted by Micky Duck
For that to work your scope would have to be about a foot above the line of the bore.Quote:
Originally Posted by timattalon
Managed to find an article on the ammo
It said that they had sighted it in at 75 yards and that made and I quote’ for an inch or so drop at a100’ anyway the plan is for 60 and below so wish us luck ��
In order to still be rising at sixty....it would either need to be much faster than subsonic and/or scope height be rediculasly high.or to be sighted in further than sixty....you just play with zeroed for number till you match what you desire.Quote:
Originally Posted by timattalon
Might be heavier,might be more pointy,but numbers won't change much when going that slow
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.
