Shooting low

Ebola

Ebola

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I have a Beretta 90-two. It shoots low as most Berettas do from what I have read. Im to cheap to order a new front sight to compensate for this.

I remember reading a mathematical equation once that will help me by telling me how far to grind down my front sight to bring my POI up. Can anyone help me out with said equation?
 
It's scale or similar triangles. The measure you're shooting low divided by the distance to the target will be equal to the amount you need to file away divided by the sight baseline length. So the distance low divided by the distance to target times the sight baseline length will equal the amount you need to remove.

To keep this all correct you need to convert the distance to target into inches or cm's to go with the inches or cm's you're using to measure the other distances.

And do NOT just take that much off at home and expect it to be correct. You want to use this as a quide for a first shortening but leave a little extra in place. Take a file to the range with you for the final trimming.

A good way to form the last bit of front blade removal is to field strip the gun so you're working with just the slide. Use a shim that covers 1/2 of the file's face and that is roughly 2 to 3mm's thick to support the rear sight. To use this hold the rear sight against the shim with some pressure and with your other hand apply some pressure at the front sight. Move the slide along the file maintaining both contacts.

This will ensure that the rear of the top edge is the one you see for lining up with the rear notch and that you don't get any glare off the top of the front blade.

And sneak up on the final cut or two with lots of shooting in between. Also realize that the ammo power and bullet weight changes the POI. So shoot with a couple of different brands to find a happy medium.

When I've trimmed a sight like this I also shoot the gun in the same way that I'm going to shoot it regularly. Using a rest for tighter groups will affect the group elevation. So only use a rest for this trimming if you'll be shooting from such a rest frequently. Otherwise just shoot normally for the final sighting in.
 
That would be:
1911 (or any other) sight adjustment formula: (Sight radius with 5" barrel=6" ,1 yd = 36"),just because i shoot 1911s...you have to measure your beretta.

POI/POA difference in inches x sight radius in inches
---------------------------------------------------- = change in inches
Target distance in inches

Hope that helps.
CG
 
Ebola said:
I have a Beretta 90-two. It shoots low as most Berettas do from what I have read. Im to cheap to order a new front sight to compensate for this.
I remember reading a mathematical equation once that will help me by telling me how far to grind down my front sight to bring my POI up. Can anyone help me out with said equation?
Click to expand...

I was going to PM you just the other day to see if you wanted to meet at the range! (but I got too busy to go) I can bring a very small flat fine file out of my tool box.. shoot, file, repeat until desired POI! I need to get out more, I've got a scope to sight in on a .223 I built... and test some hand loads!
 
Heavier bullet ammo raises the PoI. Also if it has a fiber front sight you can alight the center of the fiber with the top edge of the rear sight.
 
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