Rear sight elevator step POI change
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Rear sight elevator step POI change
How much change in point of impact change (MOA) per step of buckhorn rear sight at 100 yds.? A rough estimate would be ok. Thanks
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Re: Rear sight elevator step POI change
I'm not sure there's an easy way to find the number to this. The factory sights aren't calibrated or specified as to their adjustment value. Plus, it would change with different length barrels.
There are two ways I can think of to find the answer to your question:
- Practically; where you shoot some groups while using different adjustments on the rear sight.
- Mathematically; where you measure the distance between the front & rear sight, as well as the difference in height per step on the rear sight. Then run the math to find the angle in MOA.
There are two ways I can think of to find the answer to your question:
- Practically; where you shoot some groups while using different adjustments on the rear sight.
- Mathematically; where you measure the distance between the front & rear sight, as well as the difference in height per step on the rear sight. Then run the math to find the angle in MOA.
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Re: Rear sight elevator step POI change
I was able to calculate the required front sight height to move point of impact. My 44 mag loads were 12” higher than sight adjustment allowed. Sight radius is 21.5”, I need about 3/32” higher front sight. Rear sight steps are about 1/32” increments. Using similar calculations, I get about 5”of elevation change per step. I’ll check that out on the range later this week.
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Re: Rear sight elevator step POI change
I get 0.072" per your above figures.Blind Hawg wrote:I was able to calculate the required front sight height to move point of impact. My 44 mag loads were 12” higher than sight adjustment allowed. Sight radius is 21.5”, I need about 3/32” higher front sight. Rear sight steps are about 1/32” increments. Using similar calculations, I get about 5”of elevation change per step. I’ll check that out on the range later this week.
https://www.dillonprecision.com/sight-c ... lator.html
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Re: Rear sight elevator step POI change
That's what I plugged into it but by all means, check that. Just click on the link and fill in the fields.Blind Hawg wrote:At 100 yds?
This is just a FWIW... when I'd correcting elevation for these type of sights, I make the correction so I'm zeroed on the first or second step of the sight elevator. Gives me a little wiggle room.
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Re: Rear sight elevator step POI change
It's probably just useless blather on my part, but when I bought my first R92 in 2013 (44 mag) the rear sight elevator would just NOT hold the sight leaf up due to recoil. I tried to file the steps to be a bit "flatter", which worked some ... then I remembered having an old Daisey pellet gun stuck back in a closet. The plastic elevator on that old thing fit perfectly, had more "steps", and the steps were crisp and sharp. A couple of years later I put a Weaver Scout Scope on it (thank you, RD, for the recommendation) and saved back the Daisey elevator. Then, in late 2015 I traded into a stainless .357 R92 and the Daisey elevator went on it almost immediately - and still on it.
Fortunately, neither of my two R92's have the short front sight to have to deal with, but one of my shooting buddies has a 16" R92 (44 mag) that came with the overly short front sight. I think it shot about 6-7 inches high at 50 yards with the sight leaf sitting on the barrel. After three years he finally got a taller front sight from Steve's Guns that fixed it up proper. The short front sight seems to be a common problem with the Rossi guns, at least in the last 6-8 years I've been following them.
jd
Fortunately, neither of my two R92's have the short front sight to have to deal with, but one of my shooting buddies has a 16" R92 (44 mag) that came with the overly short front sight. I think it shot about 6-7 inches high at 50 yards with the sight leaf sitting on the barrel. After three years he finally got a taller front sight from Steve's Guns that fixed it up proper. The short front sight seems to be a common problem with the Rossi guns, at least in the last 6-8 years I've been following them.
jd
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Re: Rear sight elevator step POI change
mr surveyor wrote:It's probably just useless blather on my part, but when I bought my first R92 in 2013 (44 mag) the rear sight elevator would just NOT hold the sight leaf up due to recoil. I tried to file the steps to be a bit "flatter", which worked some ... then I remembered having an old Daisey pellet gun stuck back in a closet. The plastic elevator on that old thing fit perfectly, had more "steps", and the steps were crisp and sharp. A couple of years later I put a Weaver Scout Scope on it (thank you, RD, for the recommendation) and saved back the Daisey elevator. Then, in late 2015 I traded into a stainless .357 R92 and the Daisey elevator went on it almost immediately - and still on it.
Fortunately, neither of my two R92's have the short front sight to have to deal with, but one of my shooting buddies has a 16" R92 (44 mag) that came with the overly short front sight. I think it shot about 6-7 inches high at 50 yards with the sight leaf sitting on the barrel. After three years he finally got a taller front sight from Steve's Guns that fixed it up proper. The short front sight seems to be a common problem with the Rossi guns, at least in the last 6-8 years I've been following them.
jd
No it's not useless blather. I've had all those problems with R92 sights.
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Re: Rear sight elevator step POI change
Nothing is completly absolute with iron sights. Different bullets, powder charges and barrel lengths come into play. Plenty of range time with your chosen load will give you your answer.
Ackley was right all along
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Re: Rear sight elevator step POI change
Range results: My reload, 240 gr JSP over 22 gr 2400, 24" bbl .44 mag R92 @ 100 yds. 2 elevator rear sight steps change (.030" ea step) yielded 10" change in point of impact. 5 MOA Per step. Confirmed my calculations using online triangle calculator.