1975 BLR in 308....trying to sight in factory sights

Discussion in 'Browning BLR Rifle' started by joc1212, May 19, 2017.

  1. joc1212

    joc1212 Copper BB

    I bought this gun used and am trying to sight it in at 100 yards with the factory open sights...not having much luck at 100 yards....one out of 5 shots hit the target when I aimed way low.
    Where did Browning set the sights from the factory??? Where should I start elevation wise....I'll worry about windage when I get on the paper.
    Thanks for you help....(boy this rifle kicks worse than any of my other 308's) hope we can get it sighted quick...
  2. SHOOTER13

    SHOOTER13 Guest

    How is YOUR sight at age 72 Joc...!?

    Do you wear corrective lenses...?

    Factory "iron" sights are usually set at 100 yards for a rifle....
    Last edited by a moderator: May 20, 2017
  3. joc1212

    joc1212 Copper BB

    you're right on track I do wear progressive corrective lenses. I have scopes on all my other rifles and wanted to carry this BLR as a truck gun and not worry about a scope for right now. I just bought it used and certainly should be able to hit a piece of red poster paper at 100 yds. I've put the elevation all the way down and will now start at 50 yards and work from there. BTW, I can shoot my 1903A3 and my M1 pretty good with the battle sights on them.
    SHOOTER13 likes this.
  4. SHOOTER13

    SHOOTER13 Guest

    Try this method for a scoped rifle:

    { Remember the caliber and different weights of bullets used within that caliber affect accuracy }

    Get in a steady position at a shooting bench with the rifle pointed at the 25 yard target. If you are using a variable power scope, set it to the highest practical power. In other words, the highest power that delivers a sharp, clear image. This may not be the maximum power. Many scopes look better slightly below their maximum magnification. For example, the view through a 3-9x scope may look better at 7x or 8x than it does at 9x.

    Now load one round into the chamber and prepare to shoot. Put the crosshairs directly on the center of that big, black bull. Before you shoot, close your eyes for 10 seconds and then open them. Did the crosshair drift off the center of the target while your shooting eye was closed? If it did it means that your muscles are under tension trying to keep the rifle on target. Shift your position slightly until you can close your eyes and find that the rifle is still aimed directly at the point of aim when you open them. Now your muscles are properly relaxed and you are in a position to do your best shooting. Go through this little routine before you fire every shot.
    Carefully fire one round. Call the shot. If the crosshair was on the center of the target when the gun fired, you don't need to shoot again. If it wasn't, mark that hole as a flyer and shoot again. Get a perfect surprise break.

    Okay, examine the target and find the bullet hole. You can probably see it through your rifle scope, and certainly through your spotting scope. (You did bring a spotting scope, didn't you?) Even though you bore sighted your rifle the bullet hole is probably not going to be in the center of the target at 25 yards, but at least it should be somewhere on the paper. Measure (or at least accurately estimate) its distance from the "X" in the center of the bull. Let's say, for example, that single perfect shot hit 3 inches high and 2 inches to the left of the center of the target.

    Adjust your scope the number of clicks or increments required to move the point of impact to the center of the target. For example, let's say the instructions that came with your scope advise that each click moves the point of impact 1/4 MOA, which is 1/4 inch at 100 yards. Fine, but since we are shooting at only 25 yards, we will need to multiply the number of clicks by 4.

    To move the point of impact down the required 3" at 100 yards would require 12 clicks (four clicks per inch). At 25 yards, remember, we will have to multiply the number of clicks by 4, so turn the elevation adjustment in the down direction 48 clicks (12 x 4 = 48). It is a good idea to go a little past the new setting and then come back whenever adjusting a scope. I'd turn, say, 50 clicks and then come back 2 clicks for a total of 48 clicks down. This helps settle the adjustments of many scopes. I also tap the adjustment dials after setting them, for the same reason.

    Now adjust the windage. You need to move the point of impact 2 inches to the right, which at 100 yards would require 8 clicks. At 25 yards that means 32 clicks (8 x 4 = 32). Turn the windage adjustment a total of 32 clicks to the right (usually marked "R" on most scopes).

    Okay, now get back into that comfortable position and fire one more perfect shot at the 25 yard target. Ideally, if the scope's adjustments are accurate, it should hit inside the "10-ring" of a 100 yard small bore rifle target. If it does, your preliminary 25 yard sighting is close enough. No need to waste ammunition getting it perfect. You will do that at 100 yards.

    If the second shot is not within an inch of the center of the target, you will have to adjust the scope again. By the third or fourth shot and adjustment of the scope the bullet should be landing inside of the 10-ring. If it isn't, something may be wrong. Check the scope mount screws for tightness. They must allow absolutely no movement of the scope under recoil.

    Let's assume that your rifle is now hitting within an inch or less of the point of aim at 25 yards. Great, now it will at least be on the paper at 100 yards. Hopefully, it has only taken 2 or 3 shots to achieve this. The rifle's barrel is probably not too hot, your shoulder is still in good shape, and you haven't wasted a lot of ammunition.

    Now put up a 100 yard target. You can use the 100 yard small bore rifle target, but I prefer the Outers "Score Keeper" target. It has a central bull's-eye and 4 smaller bulls, one in each corner (which I ignore). Best of all, it is overlaid with 1 inch grid lines, making it easy to see how far your bullet holes are from the point of aim using only your spotting scope--no need to measure. This saves a lot of steps when shooting at 100 yards.

    Wait until your rifle barrel has cooled to the ambient temperature (keep it out of the sun), and then get back into your comfortable bench rest shooting position. Remember to close your eyes before you shoot to check for a perfect, tension free hold. This time you will fire 3 shots, slowly and very carefully, at the exact center of the 100 yard target. Take your time and make each shot a perfect surprise break. Call your shots and check each one through your spotting scope. That way, if you call a flyer, you will know which bullet hole to disregard. Re-shoot any flyers so that you have 3 good shots on the target.

    Now estimate the center point of impact for the three bullet holes. If you have an accurate rifle and shot it well, they should be within about a 3 inch (or smaller) circle somewhere on the 100 yard target, so this should not be too difficult.
  5. SHOOTER13

    SHOOTER13 Guest

    Sighting in with iron sights is a much more complicated matter.

    Let’s consider barrel-mounted hunting sights first, such as found on vintage Browning, Winchester and Marlin lever guns, modern made replicas thereof and a vast array of other types of iron-sighted long guns. Almost all of these, when in rifle form, have sights set in barrel dovetails—front and rear. Not so for carbines. Their front sights are either part of the front barrel band or blades set in studs silver-soldered atop the barrel.

    Moving a dovetailed rear sight is easy. First ascertain whether there is a “cramp” screw in it. This is a screw to ensure tightness even if some wear or age allows the rear sight to loosen in its dovetail. This screw—if there—need be removed. Then with brass punch and hammer and with the rifle on a solid surface, tap on the rear sight to move it in the direction needed. Just as with scopes, a rear sight should move in the direction you want the bullets to move.

    Iron Sight Tip No. 1:

    Before pounding on the rear sight pad the rifle so it’s wood, plastic or metal does not become marred. Also, having someone holding it tightly helps. If a sight is recalcitrant about moving, then dose it with some penetrating oil for awhile. This is often needed with vintage rifles.

    The same is true for front sights only in reverse—if the sight is set in a dovetail. That is, drift the front sight in the opposite direction you want the bullets to go. A natural question here is, “How much do you move the sight?” Well, that is purely a shoot-and-see proposition. Move the sight perceptibly and shoot—again, a 3-shot group is better than a single round.

    Iron Sight Tip No. 2:

    In order to perceive how much either a front or rear sight has moved, put a strip of masking tape along it. Then with a pencil, mark some index lines on sight and tape. The amount of movement will then be easy to discern.

    So far we have discussed only zeroing iron sights for windage. What about elevation? Some open-sighted rifles have a rear sight with slider so elevation can be raised. What if the rifle still shoots too high with the rear sight bottomed out? Or what if the rear sight’s slider does not give enough elevation to bring point of impact where needed?

    This is when the front sight must be replaced or altered. Again, keep in mind the front sight must be moved opposite from where you want bullets to impact. If a rifle is impacting bullets too high, then a taller front sight is needed; too low and a shorter one is required. Things can get sticky here if some impetuous soul starts grinding or filing on the sight without having some backup sight blades on hand.
    Last edited by a moderator: May 20, 2017
  6. SHOOTER13

    SHOOTER13 Guest

    Iron Sight Tip No. 3:

    If you have many rifles of the same make needing front sight adjustment, it helps to have one of the special tools (a “sight pusher”) made especially for that. I have enough Mauser military rifles to justify the tool’s cost. It sits over the end of the barrel and by screw pressure will push the sight whichever way is necessary. Instead of pounding on sight blades I can now minutely move them and do so quickly.

    When drifting rear and front sights in their dovetails, especially in vintage firearms, don’t be surprised if one or the other ends up sitting noticeably off-center. Admittedly, this looks funny.

    Iron Sight Tip No. 4:

    To lessen the visual impact of an off-center sight, take up part of the adjustment needed with one sight and part with the other—taking for granted here both front and rear sights are in dovetails. For example, if a rifle is shooting quite a bit left of center, then move the rear sight right and next move the front sight left. This way when zero is achieved, neither one should be too far off center.

    Now we get to tang-mounted peep sights. It would actually take a book to fully describe all the ins and outs of old-style, target-grade Vernier tang peep sights and their corresponding front types. Space will not allow all that here but we can hit the high points. One important detail is tang-mounted sights need to be set level and the fact is not all rifle tangs are square with the rest of the action. Therefore, it is not uncommon for tang sights to need shimming to make them straight.

    First we need to know which way they lean. A very detailed way is to hang a plumb line from your shop’s ceiling so it is directly in front of your rifle’s bore when it is secured in a vise. Then raise the sight’s eyecup and see if it stays aligned with the string as it climbs the sight staff.

    If it moves off right or left then you know which way the sight leans. A far easier but less precise method is to use a small T-square with spirit level, holding it against the side of the sight staff. Then shim the base, until the spirit level says the sight is square with the world.

    Iron Sight Tip No. 5:

    You don’t have to keep a bunch of different thicknesses of brass shims on hand. Pieces of soda or beer cans work as well.

    Now... the idea of mechanical zero. For a windage adjustable peep sight to be worth a hoot, the rifle must have a mechanical zero. The rear sight must be at its center setting when the rifle is hitting zero. This way, as wind conditions change, adjustments can be made. But if the breezes die, setting the sight back to zero returns the point of impact also to zero.

    Otherwise windage adjustable rear sights are useless in regards to repeatability.

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