Tips on zeroing M1A rifles for long ranges?

GearSolidMetal

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Hey guys and especially @Protectandserve, I've purchased two M1A rifles about two years ago and I've been too busy to get them both zeroed. I'm finally taking a few days off from driving a truck across the country and going to finally get both of my M1As zeroed at a 100 yard indoor shooting range.

My dad even gave me a Caldwell Led Sled for Christmas.
caldwell_820300_c_12.jpg

Never used one of these before, so it'll either make this easier, or far more complicated.... but I'm leaning towards easier.

The trick is, I've never personally zeroed an M1A, only M16s when I was in the service, and that was a decade ago so I'm would be alittle rusty with that.

I've seen a few youtube videos, but anyone can make a youtube video. For those that do know of reliable youtubers, which one would you recommend for zeroing an M1A?

So I'm not going this completely blind, but any advice to smooth over any rough areas of the process would be appreciated.

Oh, by the way, I'm zeroing my Socom 16, with open sights.
m1a-Socom16.png.456b56c83b50ca6a2e5d8a2a09622004.png

Want to eventually get it zeroed to be pinpoint accurate up to 300 yards.

(Yes I know I can't zero a rifle to 300 yards at a 100 yard range. The indoor range is just the first step.)

mp9820_m1a_precision_adj.jpg

5423413_01_nikon_m_308_in_nikon_mount_640.jpg

And I have my M1A Precision series, with a picatinny rail with Nikon M-308 optics, and want to get the open sights zeroed out to 300 yards as well, and get the optics zeroed out to 600 yards. (The optics say they're accurate up to 800 yards, but lets say I want to be realistic and have full faith I can hit a target at 600 yards).

Don't mean to post all my equiptment as if I'm bragging, just posting them to give full information so you guys don't have to ask what equiptment I have.
 
Biggest thing with the M1A is securing your scope properly. Make sure you get it mounted solidly, locktite the screws too. Mine loosened up a bit and my zero started getting affected. Your owners manual on the scope should also have a ballistic chart.

You can zero the irons at a closer range, 25 yards to get it zeroed and then make adjustments from there for your 100 yard zero to save you ammo(similar to Army zeroing procedure). If your trying to do it at 100, have a good zero target and a spotting scope.

Check some of the resources online for your desired bullet weight and drop. Use this chart and decide your zero you want to use. Then test your ammo for a comparison, make your own DOPE (Data on Previous Engagements) Chart.
http://www.snipercentral.com/308-winchester-7-62x51mm-nato/
Here is the link to the FM for the M14.
http://www.m14.ca/FM/FM23_8A.pdf
http://www.snipercentral.com/308-winchester-7-62x51mm-nato/
@Chesten_Hesten and @RerouteToRemain can also help with the long distance zeros, set ups etc. I'd defer to them, they shoot a lot more long range stuff than me and have more experience with that stuff.

That said, I love mine. Probably my favorite gun to shoot and bring to the range. Mine has the JAE Stock, Millet Scope, bipod and rear mono pod, makes it super easy to shoot supported and actually easy on new shooters, even though it is a 308 round. Only gun that people constantly ask to shoot and walk away from going "wow".
 
(Yes I know I can't zero a rifle to 300 yards at a 100 yard range. The indoor range is just the first step.)


Not necessarily. Depends on ballistics I think. For example, if you zero an AR at 50 yards it's zeroed at 200 yards (more or less).
 
Hey guys, I've purchased two M1A rifles about two years ago and I've been too busy to get them both zeroed. I'm finally taking a few days off from driving a truck across the country and going to finally get both of my M1As zeroed at a 100 yard indoor shooting range.

My dad even gave me a Caldwell Led Sled for Christmas.
caldwell_820300_c_12.jpg

Never used one of these before, so it'll either make this easier, or far more complicated.... but I'm leaning towards easier.

The trick is, I've never personally zeroed an M1A, only M16s when I was in the service, and that was a decade ago so I'm would be alittle rusty with that.

I've seen a few youtube videos, but anyone can make a youtube video. For those that do know of reliable youtubers, which one would you recommend for zeroing an M1A?

So I'm not going this completely blind, but any advice to smooth over any rough areas of the process would be appreciated.

Oh, by the way, I'm zeroing my Socom 16, with open sights.
m1a-Socom16.png.456b56c83b50ca6a2e5d8a2a09622004.png

Want to eventually get it zeroed to be pinpoint accurate up to 300 yards.

(Yes I know I can't zero a rifle to 300 yards at a 100 yard range. The indoor range is just the first step.)

mp9820_m1a_precision_adj.jpg

5423413_01_nikon_m_308_in_nikon_mount_640.jpg

And I have my M1A Precision series, with a picatinny rail with Nikon M-308 optics, and want to get the open sights zeroed out to 300 yards as well, and get the optics zeroed out to 600 yards. (The optics say they're accurate up to 800 yards, but lets say I want to be realistic and have full faith I can hit a target at 600 yards).

Don't mean to post all my equiptment as if I'm bragging, just posting them to give full information so you guys don't have to ask what equiptment I have.

Proper mounting of the scope is a must. Proper torque value on the rings and mount, scope level with the rifle. Cant will mess up the bdc at farther distances.

Providing this is your reticle.
649938.jpg


Your scope was intended to be zeroed at 100 yards with the dots being roughly zeros for 2-800. The 3rd open dot would be a zero for 600. However because your scope is 2nd focal plane those hold over dots will only be accurate at a certain magnification (your manual should let you know).

So you could either just keep it at that magnification so you can use the hold overs(and adjust it to the 3rd open dot being a true zero at 600, making the cross hair and other dots slightly off as usually a bdc will be a little bit off as it is set up for a specific barrel length, round, fps, etc or maybe you will get lucky and it will be dead nuts) or you could get the center cross hair at 600 but the dots would be worthless.

Btw here is a rough ballistics chart for the round and barrel length at 600 yards zero.

Range (yd) Drop (in) Velocity (fps) Energy (ft-lb)
0 -1.5 2600 2521
100 17.3 2422 2188
200 30.1 2251 1890
300 36.0 2087 1625
400 34.2 1930 1389
500 22.8 1781 1183
600 0.0 1641 1004
700 -35.0 1509 850
800 -86.1 1390 720
900 -155.8 1283 614
1000 -247.0 1192 530



Here is a ballistics chart for the socom.

Range (yd) Drop (in) Velocity (fps) Energy (ft-lb)
0 -1.5 2450 2239
50 3.1 2363 2083
100 6.1 2278 1936
150 7.4 2195 1797
200 6.9 2113 1665
250 4.5 2033 1542
300 0.0 1955 1425
350 -6.7 1878 1315
400 -16.0 1804 1214
450 -28.1 1732 1119
500 -43.1 1663 1031
550 -61.2 1595 949
600 -82.4 1530 873


You can mess with more charts here. 22" fgmm 168gr is roughly 2600 and the 16" is roughly 2450.

https://www.federalpremium.com/ballistics_calculator/
 
Not necessarily. Depends on ballistics I think. For example, if you zero an AR at 50 yards it's zeroed at 200 yards (more or less).


@GearSolidMetal

That's where the ballistic charts come in. For the 16" barrel, 6" high at 100 should in theory be zeroed at 300. For your 22" barrel 5" high at 100 should be zeroed at 300.
 
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Biggest thing with the M1A is securing your scope properly. Make sure you get it mounted solidly, locktite the screws too.

Gonna follow this guide step by step for that.



Seems reliable. Is there a specific type of locktite you'd recommend?

Mine loosened up a bit and my zero started getting affected. Your owners manual on the scope should also have a ballistic chart.

Gotchya. The Nikon M-308's reticle is specifically for 308 ammo 168 grain (Winchester).

reticle_251_ts.gif


I plan on getting both rifle's open sights zeroed using the cheaper 145 grain ammo, and use the 168 exclusively with the optics.

But, I still plan on testing the accuracy on 50 yard incriments. Call me weird, but when I say pin-point accurate, I mean 3-shot groups within inches apart. But, at the 500/600 yard distances, I'll settle for 6 inch radius for the groups.

Back in the Army I was pissed when I shot less than 39 out of 40 on the qualifying range. I swear some of those targets could be shot with direct hits and they wouldn't go down.

You can zero the irons at a closer range, 25 yards to get it zeroed and then make adjustments from there for your 100 yard zero to save you ammo(similar to Army zeroing procedure). If your trying to do it at 100, have a good zero target and a spotting scope.

Its an indoor range, so no spotting scope required. But getting it zeroed at 25 yards is good advice to avoid wasting time by having to reel in my targets every few minutes.

Check some of the resources online for your desired bullet weight and drop. Use this chart and decide your zero you want to use. Then test your ammo for a comparison, make your own DOPE (Data on Previous Engagements) Chart.
http://www.snipercentral.com/308-winchester-7-62x51mm-nato/
Here is the link to the FM for the M14.
http://www.m14.ca/FM/FM23_8A.pd

Solid links for me to review. Thanks for posting them.

They'll be useful for when I take them to an outdoor range. I'll only go when there's perfect weather conditions, we all know weather has a habit of changing on a minute-by-minute basis, especially wind speed and direction.
That said, I love mine. Probably my favorite gun to shoot and bring to the range. Mine has the JAE Stock, Millet Scope, bipod and rear mono pod, makes it super easy to shoot supported and actually easy on new shooters, even though it is a 308 round. Only gun that people constantly ask to shoot and walk away from going "wow"

Hell, my Precision Series is already heavy as hell with the rail and optics on it. If I added a bipod and whatever else, I bet it could get up to 14 pounds. Lol.

My S16 will be the go-to rifle, with the Precision being the one for when I know the target is past 300 yards.
 
Proper mounting of the scope is a must. Proper torque value on the rings and mount, scope level with the rifle. Cant will mess up the bdc at farther distances.

Providing this is your reticle.
649938.jpg


Your scope was intended to be zeroed at 100 yards with the dots being roughly zeros for 2-800. The 3rd open dot would be a zero for 600. However because your scope is 2nd focal plane those hold over dots will only be accurate at a certain magnification (your manual should let you know).

Yup, this is why I get the optics zeroed, I'm never touching the magnification again.

I did my research on the optics before I pressed 'Order Now.' I'm not an impulse buyer, and probably read at least a dozen reviews from different sites.

The plan is to be strict on the 300 yards. 168 grain Winchester for over 300, 145 grain with open sights with either the S16 or Precision for under 300.

Thanks for the ballistic charts, they're always worth reviewing.
 
Yup, this is why I get the optics zeroed, I'm never touching the magnification again.

I did my research on the optics before I pressed 'Order Now.' I'm not an impulse buyer, and probably read at least a dozen reviews from different sites.

The plan is to be strict on the 300 yards. 168 grain Winchester for over 300, 145 grain with open sights with either the S16 or Precision for under 300.

Thanks for the ballistic charts, they're always worth reviewing.

Yeah just check the manual to see what magnification the bdc is set to be used at. Zero at 100 and then fine tune the zero for the 600 yard open dot when you can shoot at that distance.
 
Everythig listed from the other guys looks good.

@Protectandserve @mushishi @Graverobber im currently in San Fran, headed to Santa Cruz, then Monterey. No idea how close that is to any of you.

Wanna meet for dinner or lunch with the wife and I? Totally cool if not. We're just poodling round like old farts.
 
got a cold, bro.
would hate to give it to you....or your wife
another time perhaps
 
Everythig listed from the other guys looks good.

@Protectandserve @mushishi @Graverobber im currently in San Fran, headed to Santa Cruz, then Monterey. No idea how close that is to any of you.

Wanna meet for dinner or lunch with the wife and I? Totally cool if not. We're just poodling round like old farts.
Damn I was just up there for Christmas. I'm in Southern Ca and have to work this weekend.
 
Damn I was just up there for Christmas. I'm in Southern Ca and have to work this weekend.


No worries. We'll be in Monterey till the 4th. Wife has me touring parks and lighthouses. Hope to visit some racing shops at least, hobb knob with fellow wizards.

Cheers and happy new year!
 
No worries. We'll be in Monterey till the 4th. Wife has me touring parks and lighthouses. Hope to visit some racing shops at least, hobb knob with fellow wizards.

Cheers and happy new year!
17 Mile drive is worth the trip some awesome scenery, good photo stops and just relaxing time. Also eat at the Pebble Beach Golf Club House, damn good food, nice views of the ocean too.

Monterey is an awesome place, Carmel has some nice shops and beaches too.
 
17 Mile drive is worth the trip some awesome scenery, good photo stops and just relaxing time. Also eat at the Pebble Beach Golf Club House, damn good food, nice views of the ocean too.

Monterey is an awesome place, Carmel has some nice shops and beaches too.

Will pass this along to the boss, I mean wife!

She says there's too many Chinese tourists on 17 mile drive!

 
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17 Mile drive is worth the trip some awesome scenery, good photo stops and just relaxing time. Also eat at the Pebble Beach Golf Club House, damn good food, nice views of the ocean too.

Monterey is an awesome place, Carmel has some nice shops and beaches too.


Driving here is a vacation unto itself for me. Everyone holds nice lines and carries corner speed. Everyone "moves". There hasnt been driving like this in Texas since the 1980s.
 
^Also Lagunaseca Speedway is a short drive from Monterey...

Absolutely, last time here, (2009)
Got to catch the MotoGP practice. Enjoyed that immensely.

Wife wants to check the redwood parks now so well be hiking next to the tree trunks.

Weather's nice here. Cold and rainy back in houston.

Thanks for all the suggestions.

Cheers.
 
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