Refresh my memory if im sighting one of my centerfires in on a 25m range roughly how high or low do i want it shooting done a couple of scope swaps and its been a while the 2 main ones are 7x57 and a 308
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Refresh my memory if im sighting one of my centerfires in on a 25m range roughly how high or low do i want it shooting done a couple of scope swaps and its been a while the 2 main ones are 7x57 and a 308
Scope height above the bore?
Intended zero?
Pretty much bang on at 25m for a 200m zero on my rifles is what I use to check or get on paper when resighting.
About 200m zero should be good for both
IIRC it's 40m when the bullet passes the line of sight on a 200m zero. Or maybe that's 250m...
You want it to be roughly the height of the scope low at 25y. So roughly an inch or so low.
If you zero it at 25y you will be very high at 100.
300 win mag bey hits the middle every time
Must be you a lot of people start at a closer range so you not fuking around so much at 100 or 200 trying to get it on paper
Nothing wrong with short range sighting in.
Do what works for you.
Check if you can at 100- 200m.
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Not odd at all.
I know where all my rifles shoot when zeroed at the correct range, and at 50m.
I also know my exact boresight at 10m.
Quick check with a shot or look down the barrel is all that's needed to confirm things. I trust either and it has never let me down.
Can also save a bit of doubt if you or someone else has a miss with your rifle.
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I just draw a 1" circle on my target, go out to 100yds and pull the bolt out and bore site it then away you go, 99% of the time on paper
If you are 1cm off perfect left or right at 25m, that's 4cm at 100m, and 8cm at 200m, 16cm at 300m.
Even 5mm adds up to 2cm at 100 and 4cm at 200m, 8cm at 300m etc etc. That's quite a lot and you would need to shoot perfect tiny groups with zero left or right deviation at 25m to even get close.
It really adds up.
Iv got on paper at 25m with what I thought should be a good zero many times only to find it substantially off at 100+
I guess people have different ideas of precision.
Zeroing, yes I agree, hence my comment about checking (once already zeroed at 200), or starting at 25m to get on paper (before shooting further out). For a 200m zero I much prefer actually shooting at 200m rather than 2 inches high at 100m, but sometimes you don't have that choice.
ok im not going to do my rifles just off 25m after ive got it ok at 25 i can go out to 100 i can go 1200 or more if i want to where i shoot i had a quick go the other weekend and couldnt hit the paper at 100 so starting at 25 i dont shoot at live targets past 200 anyway
You can sight in at 100m.
Then come back and check at 25m 50m whatever.
Some work out where first impact is at zero say 26m and check at that.
There was chapter devoted to in in the Grant book "The Sharpshooter".
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I sight all my rifles at 25, after bore sighting. Draw a 15mm black dot on white paper, fire one shot, and shift scope accordingly. Usually it only takes 2 shots, you can see them easily at 25. Then I move back to 100 and fire a 3 shot group. Depending on calibre, the group is usually with a few centimetres, and then adjust scope accordingly. But most rifles sighted at 25 will be very close at 100. And most of my rifles only need the 2 at 25, and the 3 shot group at 100 to be bang on.
Running the numbers through Strelok with my favourite loads with a 200m zero, at 25m I should be:
7mm low for 243
5mm high for 308
1mm high for 260
The 243 has higher rings, using the same scope height as on the 308 reduces it to 2mm low at 25m.
So you want to be pretty much dead on at 25m, or damn close to it.
ok cool a guy at deer stalkers was telling me about 5"high at 25 which I thought was way to high its been ages since ive done it
Don't listen.
As I have a couple of rifles here to sight in I guess I will bore sight onto paper at 100m, hash out a rough trajectory and then shoot a couple of 200m and 300m targets and see what it all looks like. Been a while since I did this without clicky dially scopes that need 2 rounds to sight in.
As long as you know where everything is going out to 200m, no need to worry too much. Further than that, then you need to worry.
For a 308 trajectory with a scope mount height of 1 1/2 inches goes through line of sight at 25 climbs 2 1/2 to 3 in high at 100, peaks around 140 at 3 1/2 and goes back through line of sight at 200 yds. So a quick start can be made at 25 but it really needs verification at 200 if that is your desired zero.
Back in the day when I was meat hunting and then farming I would often check my rifle at 25 yards. If it was dead on at 25 I knew it was close to 3" high at 100, dead on at about 250, and that I didn't need to hold over until around 350 yards. It worked fine in-spite of not knowing the exact trajectory. If I got a couple of shots nearly touching at 25 yards I thought I was a bloody marvellous shot :) I used to shoot deer between 25 and 300 yards no trouble (no range finder though).
We sure do worry about a lot of unnecessary shit nowadays.
As I can't afford PM11s anymore, I am setting up the old fashioned way. It is fun and does not test my shooting any less. When I started on the forum I had terrible rifles like a Spanish military .308 and I never went after Tahr (you guys may remember) because you had to have at least a 7mm Rem Mag. If I had that rifle now I would be off. Who cares, it goes bang, get closer.
Might track the fella I sold it to down and see if he will sell it to me.
If I read this right what you want to do is sight in at 25m then go straight to 200m to confirm zero and save ammo not having to shoot at 100?
If that the case this may help guessed 150gr 308 doing 2750FPS Scope 1.9" above bore
looks like 0.2 low will be close to 200 zero, I normally just get it close to center of paper at 50m and I know I am on paper at 100 or 200 and adjust from there
Go to JBM and have a play for yourself as you better know your rifle setup and ammo
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Cool ill have a look id probably do it at 25 then 100 as long as i dont get any surprises
Back in BC days when Matt Grant and Tahr were young, it was standard to sight in at 25 paces. We did a lot more checking sights at the road end and campsite then.
Two things that make a lot of difference to your 25 yr impact are the distance you sight in for (100yd vs 200m) and the sight height above bore. Theres a lot more variation between shooters these days. In the 1970s and 80s everything used low mounted 32mm scopes and sighted for '200'. About 1/2 inch high at 25 was right. But not any more.
I have mostly found with most calibers I have owned that at 25 yards your bullet will be 5-10 mm low and that will put you a bit high at 100yards. Once you are on target you need to fine tune at 100 yards about 1.5" high (give or take a bit either way ) for a 200yard zero. The 25 yard shot is a good way to confirm you zero at longer range as once you have zeroed for the longer range come back to 25 yards and fire a couple of shots and remember where they impact then you can do a quick check if need be.
I always have a couple of shots at 25m to see where it is and get it roughly zero then adjust at 50m, depending on bullet weight/load on average I'd sight it .5-.75" high at 50 and that'd do me out to 200 or so. Never been a good enough shoot to get really good grouping at 100 so always did it at 50 to get touching shots or on accurate loads 1 hole groupings. Then I'd set up water bottles at 100,150 and 200 and if I could hit those I'm good to go. bit rough but it works well enough for me.