The Accurate Reloading Forums
Filing an express sight
14 August 2012, 19:05
gunslinger55Filing an express sight
OK tired of buying NECG front sights and spending hours filing them and finding that I still am shooting way high. Time to file the fixed express sight on a CZ 550 .458. My question is: What is the best way to do this? Keep the V notch ot take a rat tail and make a arc in the bottom of the notch that fits the Front sight? The latter sounds easier.
Thanks
White Mountains Arizona
14 August 2012, 19:29
Westpacquote:
Originally posted by gunslinger55:
OK tired of buying NECG front sights and spending hours filing them and finding that I still am shooting way high.
That's funny!
Before you go any further, make sure you understand what direction the bullet will move when using the file. What direction do you want the bullet to go?
_______________________________________________________________________________
This is my rifle, there are many like it but this one is mine. My rifle is my best friend, it is my life.
14 August 2012, 22:49
BoxheadGood question as he left me confused too.
14 August 2012, 23:18
dpcdYes, good advice. but definitely deep the shallow V notch. But HOLD ON; if you are shooting high, you should NOT be filing on the front sight; that makes it shoot higher. Remember, move the rear sight in the direction you want the bullets to go; and the FRONT sight in the opposite direction. Quit filing until you get this straight. How high is it shooting, exactly? And at what range?
15 August 2012, 00:04
505GHe confused me as well.
Their are two sights so you can change the front as well.
Previously 500N with many thousands of posts !
15 August 2012, 00:33
D Humbarger
Doug Humbarger
NRA Life member
Tonkin Gulf Yacht Club 72'73.
Yankee Station
Try to look unimportant. Your enemy might be low on ammo.
15 August 2012, 01:13
Alberta CanuckOy Veh! Mein Gott en Himmel!
1. To make the rifle shoot higher, file the front sight lower. To make the rifle shoot lower, file the rear sight lower.
2. As you can't file the front sight taller, or the rear sight taller either, you just have to file on the correct one! To identify which one that is, see "1" immediately above.
As to whether to use a shallow V or either a square or "U" shape in the rear sight, I prefer a very shallow "V" for two reasons...First it lets me see more of the stuff around whatever I am aiming at and, Second, I find it easier to tell how far down into the rear sight I am holding the front sight. But to each his own. File whichever one you like best. Just make sure you are filing on the correct sight to start with.
My country gal's just a moonshiner's daughter, but I love her still.
15 August 2012, 01:20
Jim KobeFind out how much correction you need and get the proper front sight bead replacement. Brownells has a chart to show how much you may need.
Jim Kobe
10841 Oxborough Ave So
Bloomington MN 55437
952.884.6031
Professional member American Custom Gunmakers Guild
15 August 2012, 03:02
Von GruffThe formula for sight height correction is "FORS" front oposite rear same and to get the amount of correction is also simple with the amount of error in inches multiplied by the sight radiusin inches divided by the distance to target in inches.
If you are shooting 6 inches high at 50 yards and there is 24inches between your front and rear sight then
6 x 24 = 144 divided by (50x36=1800) =.08 and that is how much you would need to file the rear sight down or get a front sight .08 higher.
Put your particular numbers in this formula and you are good to go.
15 August 2012, 03:22
gunslinger55OK let me clarify-has anyone tried to fit the NECG front sights into the dovetail on a CZ-550? They make them "oversize" so you have to fit them. And I mean oversize. You have to file the base and sides to get it to fit. I've done it twice and I am sick of "guessing" what height the front sight needs to be. (yes I called etc.) but you obviously file some height off. Yes I know how to move point of impact-duh! I am going to LOWER the rear notch to lower impact point-hence filing the v-notch.
Sorry for the confusion LOL
White Mountains Arizona
15 August 2012, 05:38
craigsterSight height calculator:
http://www.brownells.com/.aspx...ht_Height_Calculator15 August 2012, 17:36
Jim Kobequote:
Originally posted by gunslinger55:
OK let me clarify-has anyone tried to fit the NECG front sights into the dovetail on a CZ-550? They make them "oversize" so you have to fit them. And I mean oversize. You have to file the base and sides to get it to fit. I've done it twice and I am sick of "guessing" what height the front sight needs to be. (yes I called etc.) but you obviously file some height off. Yes I know how to move point of impact-duh! I am going to LOWER the rear notch to lower impact point-hence filing the v-notch.
Sorry for the confusion LOL
DON'T take any material off the sides of the front side dovetail!!!
the amount to take off of the bottom is minimal really and won't affect the overall height. Find out how much you need and then fit the insert, not rocket science.
Jim Kobe
10841 Oxborough Ave So
Bloomington MN 55437
952.884.6031
Professional member American Custom Gunmakers Guild
25 August 2012, 07:22
tin canquote:
Originally posted by D Humbarger:
HA!
25 August 2012, 17:20
D Humbargerquote:
Originally posted by tin can:
quote:
Originally posted by D Humbarger:
HA!
Just wanted to see how this devoloped.

Doug Humbarger
NRA Life member
Tonkin Gulf Yacht Club 72'73.
Yankee Station
Try to look unimportant. Your enemy might be low on ammo.
25 August 2012, 20:06
Duane WiebeIn the shop, we use special fixtures to hold the rear sight and blades to cut the notches with a specially ground 140 degree end mill.
Vey precise and we get it "dead nuts" Not taking in such work myself, but Steve Button also has the tools
25 August 2012, 20:06
Duane WiebeIn the shop, we use special fixtures to hold the rear sight and blades to cut the notches with a specially ground 140 degree end mill.
Vey precise and we get it "dead nuts"
25 August 2012, 21:12
meteI still prefer Patridge sights. That's what I started life using and still use it !
The square post and square notch provide more accurate vertical and horizontal indexing !

25 August 2012, 22:22
ScrollcutterMore accurate to be sure, but much slower.
For me, the patridge sight on rifle is the slowest of all sights. Might be me, but I grew up with this type of sights on revolvers.
Roger Kehr
Kehr Engraving Company
(360)456-0831
25 August 2012, 23:11
J.D.SteeleThe Patridge style can be made LOTS faster by widening the notch. The loss of precision caused by the wider notch is negligible and with most shooters it wouldn't even be enough to be measurable.
However IMO the wide vee is always fsster IF the centerline below the notch is CLEARLY delineated by a platinum line or ivory triangle.
Many years ago Finn Aagard did some testing using his own Westley Richards Mauser 458 Win Mag. He tested the original wide vee against a peep mounted on the rear bridge, comparing close-range accuracy and total firing stroke times.
IIRC he found little difference, once he became accustomed to each system. Perhaps some of you can recall this test better than I can....(grin)
Regards, Joe
__________________________
You can lead a human to logic but you can't make him think.
NRA Life since 1976. God bless America!
26 August 2012, 23:56
gunslinger55That sounds like the right way to do it!
quote:
Originally posted by Duane Wiebe:
In the shop, we use special fixtures to hold the rear sight and blades to cut the notches with a specially ground 140 degree end mill.
Vey precise and we get it "dead nuts" Not taking in such work myself, but Steve Button also has the tools
White Mountains Arizona
26 August 2012, 23:58
gunslinger55I agree. I use that style on competition handguns but I likke the peep as well. Well the gun went into the shop to get modified so it is out of my hand now! Thanks for the input
quote:
Originally posted by J.D.Steele:
The Patridge style can be made LOTS faster by widening the notch. The loss of precision caused by the wider notch is negligible and with most shooters it wouldn't even be enough to be measurable.
However IMO the wide vee is always fsster IF the centerline below the notch is CLEARLY delineated by a platinum line or ivory triangle.
Many years ago Finn Aagard did some testing using his own Westley Richards Mauser 458 Win Mag. He tested the original wide vee against a peep mounted on the rear bridge, comparing close-range accuracy and total firing stroke times.
IIRC he found little difference, once he became accustomed to each system. Perhaps some of you can recall this test better than I can....(grin)
Regards, Joe
White Mountains Arizona
14 September 2012, 12:31
lawndartquote:
I still prefer Patridge sights. That's what I started life using and still use it !
The square post and square notch provide more accurate vertical and horizontal indexing !
quote:
More accurate to be sure, but much slower.
For me, the patridge sight on rifle is the slowest of all sights. Might be me, but I grew up with this type of sights on revolvers.
My first rifle was an M-16 with a three prong flash suppressor/"C" ration cable twist off device. I have done equally well with all three types of sights - peep, partridge and shallow V.
When I started using Sakos with partridge sights I was hunting thick stuff, and left the scope at home. Then I started using the Sako peep with the 100 meter and 200 meter settings. I was young, and forgot about using a scope until I turned forty.
In bright sunlight I like the shallow V; just one leaf though. Get closer. Nothing compares to making it into shotgun range, and swinging you Rigby shotgun style.
The fixture sounds good. Hunt in the daylight, sleep or eat at dusk. Yeah, that is the ticket.
John
18 September 2012, 04:56
gunslinger55I got it all dialed in then sent it to AHR and redid it all. It was a good learning experience anyway!
White Mountains Arizona