Calibration

[Art]

I joined a gun club in February. There were a lot of reasons but one of the big ones was that they were very "user friendly when it came to shooting my military rifles. The week before last I started "tweaking" the zero of my rifles. The place I shot before only allowed shooting at 100 yards, only from the bench and only on their targets.

The week before last I took my M1 out. I had my 200 yard dope dialed in and sure enough it hit point of aim at 200 yards. I put up an SR target to sight the rifle in for a 6:00 o'clock hold on the bull. Since I wanted to keep my 200 yard zero I loosened the rear sight screw and dialed it to the "2" on the elevation drum. I put on a few clicks of elevation, made one adjustment and was dead center with a 6:00 0"clock hold. I looked at the elevation drum and it was on the line for 300 yards. Exactly 3 clicks above my 200 yard zero.

I have to admit I was surprised at how close to the ranges indicated on the sights are to the actual point of impact of the bullets. I realize everybody looks at the sights diferently but with all these rifles zeroed at a known distance dialing in the appropriate range number puts the bullets surprisingly close to where they should be.

Today I took my two '03's to the range. I had previously "shot in" my '03A3. The battle sight on my '03 with the USMC sight modifications was dead nuts on with the battle sight at 200 yards. Remembering the experience with my M1 I moved the slide to the "3" line and fired. Dead center again at 200 yards with a 6:00 o'clock hold. I repeated this with my '03A1 with the standard M1905 rear sight. Once again I was dead center on the SR bull with a 6:00 hold.

With a 6:00 hold with all three rifles sights set for 300 yards I was 6 1/2 inches high at 200 yards. I haven't shot them at 300 yards but I bet if I do they would all hit the torso of a sillouette target with a center mass hold.

Ammunition used was HXP 63 M2 ball.

Information

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[Jim Tarleton]

A tremendous amount of work, and emperical data from actual shooters, went into calibrating those sights. They obviously did a great job.

Sounds like you were doing your part. What range do you use?

Many years ago I worked at Greenway Plaza (Conoco), before they built the "Campus" on the North side of Houston. I spent way too much time on Alabama Street.

Jim.

Jim

[Art]

I use the Bay Area Shooting Club outside of Crosby Texas. It is inexpensive, only about $120.00 per year. It dosen't have a whole lot of ameneties but is very "user friendly." They have a 200 yard range and a 50 yard range for pistols and rimfire rifles. some folks wouldn't like it because everyone is responsible for things like building their own target stands. Members do most of the maintenance.

A buddy who put me on to it calls it "The Peoples Shooting Range." I have enjoyed it and I use it frequently.

[Larry Gibson]

Art

With that m2 ammo you will be fairly well calibrated out 600 yards. Beyond that the flat based M2 bullet will fall off more rapidly than the calibrated ranges on the rear sight. The rear elevation drum of the M1 is calibrated for the M1 cartridge which used the 174 gr FMJBT at 2640 fps. The M1903A3's elevation is calibrated for the M2 ammo at what was supposed to be 2800 fps. However the velocity of M2 was reduced to 2650 fps just prior to WWII for use on NG stateside ranges. Your HXP63 M2 should be close to the original specs of M2 at 2800 fps. The ladder sight on the '03 is calibrated for the M1906 round at 2700 fps. M2 ammo that cranks an honest 2700 fps or reloads with M80 bullets at 2650 fps will be very close through 1000 yards.

FYI; the M14's elevation drum is calibrated in meters for M80/M59 ammo. It just so happens that the trajectory of m80 at 2750 fps matches the trajectory of M118 at 2550 very closely all the way to 100 meters.

Larry Gibson

[Art]

Thanks Larry

I'm aware of the difference in calibration between the M14 and M1 sights. Frankly when I was in the Army we were told to ignore the markings on the deflection and elevation drums and just counted clicks to get our battlesight zero which back then was 200 meters. If it hadn't been for wanting to keep the dope straight on zeros at two different ranges the idea of checking the calibration of the sights wouldn't have occurred to me.

Everybody sees the sights differently so there are some minor differences in sight adjustment from person to person but I am quite surprised at how close the sight calibration is, at least at practical combat ranges.