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9/22/2017 12:11:25 AM
Posted: 2/27/2006 9:25:46 AM EDT
I have my aimpoint hitting dead-on @ 50 yds, and ARMS 40L 2" IN HIGH AT @ 50 YDS. Is this a good set-up for coyote sized targets to 200 yds ?
Link Posted: 2/27/2006 9:37:52 AM EDT
coyotes are little critters and at 200 yards that red dot is gonna cover alot of them. your zero is fine its what i use as well.
Link Posted: 2/27/2006 10:31:00 AM EDT
They should both be sighted in at 50y if you want to wack anything at 200y.
Link Posted: 2/27/2006 10:34:22 AM EDT

Originally Posted By Forest:
They should both be sighted in at 50y if you want to wack anything at 200y.



dead on at 50? Now how does a 100 yard zero work out when past 100-200yards?
Link Posted: 2/27/2006 10:35:58 AM EDT
Link Posted: 2/27/2006 10:50:26 AM EDT
Going to be 50
Link Posted: 2/27/2006 10:53:17 AM EDT
[Last Edit: 2/27/2006 10:53:43 AM EDT by SWO_daddy]

Originally Posted By Forest:
They should both be sighted in at 50y if you want to wack anything at 200y.



Only because the trajectory of most 223 Remington ammo coincides at those two distances. If you are going to make that kind of recommendation, you should explain why and how since some people may not know the underlying reasons.

If someone were to ask me how to zero their rifle to hit a 200 yard target, my first answer would be zero your rifle for POI = POA at 200 yards. My second answer would be "if you do not have a 200 yard range, zero your rifle X inches high at 100 yards to be on at 200. That way the person asking understands the logic behind it.
Link Posted: 2/27/2006 10:53:52 AM EDT

Originally Posted By christ0ph:

Originally Posted By Forest:
They should both be sighted in at 50y if you want to wack anything at 200y.



dead on at 50? Now how does a 100 yard zero work out when past 100-200yards?



If you zero at 100y, then the round will be dropping past that.

At 200y it will be a couple of inches low.
Link Posted: 2/27/2006 11:09:37 AM EDT
I shoot IPSC so I sight my Aimpointin at 100 yards and the BUIS at the Bushy target thingie at 25yds.
I know from the ballistics tables that I will drop a few inches at 200yds and about 6" at 300yds. We shoot 8" armor plates @ 300yds and I just hold the Aimpoint dot on top of the plate and it flips over.
BTW I shot it yesterday at 100yds and got 3 shots in 1.25" with Winchester 45gr HJP's from WallyWorld.
My rifle is a Bushy AK Shorty A3 with a LaRue cantilever M68 and GGG BUIS with a JP trigger, speed hammer and spring set.

Bill
Link Posted: 2/27/2006 11:10:36 AM EDT
I should know this.... but why is 50yds preferred for red dots? Is it simply because it is a flat trajectory out to 200? Is it influenced by the fact that it is a common public range distance?

From running ballistics calculators with M193, it sure seems like a 35 zero is almost as flat, but gets you out to 240 and maintains +-2".

???
Link Posted: 2/27/2006 11:12:41 AM EDT

Originally Posted By Another-Bill:
I shoot IPSC so I sight my Aimpointin at 100 yards and the BUIS at the Bushy target thingie at 25yds.
I know from the ballistics tables that I will drop a few inches at 200yds and about 6" at 300yds. We shoot 8" armor plates @ 300yds and I just hold the Aimpoint dot on top of the plate and it flips over.
BTW I shot it yesterday at 100yds and got 3 shots in 1.25" with Winchester 45gr HJP's from WallyWorld.
My rifle is a Bushy AK Shorty A3 with a LaRue cantilever M68 and GGG BUIS with a JP trigger, speed hammer and spring set.

Bill



What ammo did you calculate those drop for? A 55FMJ, with a MV of 3200, zero'd at 100, shows 3" low at 200, and 11" low at 300.

www.eskimo.com/~jbm/ballistics/traj_basic/traj_basic.html
Link Posted: 2/27/2006 11:13:58 AM EDT
I have both zeroed at 50 yards. According to the IBZ the trajectory of the round is roughly this:
Muzzle - 2.5 inches low
50 yards - zero
125 yards - 2 inches high
200 yards - zero
250 yards - 2 inches low

So, with a 4 moa dot, put the dot on target and the round should be within the dot from about 30 yards out to 250.

Sarge
Link Posted: 2/27/2006 11:15:56 AM EDT
[Last Edit: 2/27/2006 11:16:48 AM EDT by Forest]

Originally Posted By FALARAK:
I should know this.... but why is 50yds preferred for red dots? Is it simply because it is a flat trajectory out to 200? Is it influenced by the fact that it is a common public range distance?



+/- 2" from 8M to 220M, plust 50y is a common range distance.

At 35y with M193 (16" barrel, 3100fps MV @15', .243BC) the bullet will rise to 5.5" at 180 yards
Link Posted: 2/27/2006 11:22:38 AM EDT

Originally Posted By Forest:
At 35y with M193 (16" barrel, 3100fps MV @15', .243BC) the bullet will rise to 5.5" at 180 yards



I see - I was using the default height over bore of 1.5 in the calculators. Makes a huge difference.

I always zero my dots to 50, because of what I have read... just when playing with the calculators, it didnt add up.

The link to the one I have above, with a 2.5" HOB, only gets up to 4.6" @180yds, using a Sierra FMJBT moving 3100. I wonder why the difference?
Link Posted: 2/27/2006 11:31:02 AM EDT

Originally Posted By FALARAK:
The link to the one I have above, with a 2.5" HOB, only gets up to 4.6" @180yds, using a Sierra FMJBT moving 3100. I wonder why the difference?


3 things I can think of:
1) Atmospheric conditions used (I used std conditions at 1400' ASL)
2) I used 2.8" HOB as many people like to use red-dots that cowitness in the lower 1/3 (so the optic sits slightly higher). This probably has the biggest effect.
3) the distance the MV reading is taken (some programs assume it's at the muzzle (0 distance) when the values I posted were recorded at 15'.
Link Posted: 2/27/2006 11:42:08 AM EDT
I zero my EOTech, Aimpoint, and BUIS at 50yds.

WIZZO
Link Posted: 2/27/2006 11:45:47 AM EDT
FALARAK

Thanks for the link to the site. Well...........I guess I've been lucky.
But if I hold a 4moa dot on top of an 8" plate, that would be 2" for 1/2
the dot and 8" for the plate which would be 10" and we actually have
about 270yds and that ridge so I have been lucky. BTW it is usually 62gr
though I have been fooling around with the Winchester white box 45grs.
They actually shoot great out of my 1/9 Bushy and great as well in my
1/7.75 Kreiger CMP rifle. I have not checked to see where they come
undone. I can't imagine them holding up at 600yds, LOL.

Bill
Link Posted: 2/27/2006 11:56:11 AM EDT
[Last Edit: 2/27/2006 11:58:59 AM EDT by Psychojeeper]
Heres the deal.
Your close in (CQB range) optics should be set for 25 to 50m max. Your BUIS should be zeroed for the 25/300m or 50/200m (whatever you prefer to use) just like your normal iron sights. This way you have close and battlefield sight options without having a red dot completely obscuring a target at 300m. Aimpoints,EoTechs, etc are great close in sights, but I have found them less than desirable at further than 100m range. If you want one optic that does both, you need to go for an ACOG(3X or 4X) or an Aimpoint and an Aimpoint3X magnifier in a fold away mount like the one from Sampson.

Just my opinion based on trying lots of the goodies out there today and over 16 years military service. All in all, other than the CQB Stuff I do, I still prefer good 'ol A-2 iron sights for every-day any condition use.
Go with whatever works for you, just dont limit yourself and look at all the options.
Link Posted: 2/27/2006 1:22:00 PM EDT
FALARAK

just thinking, but at 300yds a 4moa dot will cover 12 inches so the dot on top of an 8 inch plate will do what it did...am I wrong on this?

As far as my experience goes, my Aimpoint is no problems out to 100 yards at all and I regularly make hits well past that, as I said we shoot out to 270 yards at our IPSC club.

In speed shooting, irons are a bit slow because you can't always tell if the target was engaged and unless you at least have a NM front sight, it is pretty crude for long shots at speed. An Aimpoint gives me the confidence to move on to another target.

YMMV
Bill
Link Posted: 2/27/2006 1:33:21 PM EDT

Originally Posted By Another-Bill:
FALARAK

just thinking, but at 300yds a 4moa dot will cover 12 inches so the dot on top of an 8 inch plate will do what it did...am I wrong on this?



Well, the ammo makes a difference too.

Using M193 - with a 2.5" HOB, 100yd zero, you will actually be only 2" low at 200, and 10" low at 300.

If you were shooting an 8" plate, and held a 4MOA dot (12" coverage) directly on top - you are perfect. The radius of the dot @ 300 is 6", and the radius of the plate is 4". 10" of drop would hit the plate dead center.

Change to a 62gr, it is close enough not too matter. Change to the 45gr varmint round... it might be just enough difference for a miss.... according to the tables.
Link Posted: 2/27/2006 5:21:16 PM EDT
FALARAK

I have been shooting 62gr so I feel better because I know what I did and I didn't know how to explain it if it didn't, which it did, so it did and now I know it did because I saw it and ....whatever.

I have been playing around with the 45gr stuff but I about to order a 1000 of 62gr.

Thanks
Bill
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