[Freshman]

Gentlemen,
I have a SAI M1A Loaded in a Walnut stock, with an older SEI mount, Leupold QRW rings, and a Nikon Bushmaster 4.5-14x40 scope on top. Over the past couple of months, I have been working on properly relieving the stock channel so that it no longer interfered with the OP rod, and also machined the scope mount to better interface with the side of the receiver. I also mounted a 6-9" swiveling Harris bipod. I took it out yesterday to do some practice. At 400 yards, it seemed a bit off from what I normally DOPE at. I decided to bring the scope back to my 100yd zero and put some rounds on paper. Here are the four 5-shot groups I made, shooting from prone off the bipod with my custom handloads.

1st group (spread was worse because I was still calming down from the walk back from the targets). Notice how it is a good 2" low from the red diamond that I was aiming at. This should have been on center, as I've changed nothing about the rifle's set-up since last time I zeroed at 100 yards.

2nd group after a slight elevation adjustment. I was nice and calm now; much less noticeable jump from my heart. Still shooting a bit right, but then I noticed I had not taken my windage back to zero.

These were my next 2 groups. I shot 2 because I wanted to make sure my rifle wasn't losing zero from recoil. Pretty happy with how tight this thing is patterning.

So. The rifle is back to zero. I get my knobs all sorted out on the scope, and bring her back out to a 400 yard DOPE. Sure enough, it is just a tad off from what it was only minutes earlier. I get her dialed in, and just for shiggles, I decide to put down one more 100yd group. After these 5 rounds, I decided it was time to pack up and leave, as I was getting frustrated.

Same distance, same ammo, same shooter, same zero. I am thinking this scope is just not repeating. I know that shooting with a bipod is not straight forward, but I think my group size will attest that I am at least doing SOMETHING right. If the scope is to blame, would I be better off learning how to use the mil dots as hold-overs, and leaving the turrets at zero? Or just getting a higher quality scope? Can anyone come up with a different possible culprit?

 

[sormi]

Go to 6.21 mins on this video and watch what he has so say. Try to tap or shock your scope after every adjustment. See what happens.

Remember forward to 6.21 and watch from there..
[ame]https://www.youtube.com/watch?v=Ltqjn1aGqI0[/ame]

 

[KurtC]

The most important part of a scope is the erector system. This is the system of screws and springs that allows you to adjust the erector tube, which contains the reticle.

This is also where the bulk of the money goes. The stronger the erector system, the more likely it will hold zero, the more the scope will cost.

Economical scopes like the Nikon Buckmaster series have simple erector systems that often cannot handle the vibrations of the M14 platform. Such scopes are designed to be zeroed once and left alone, using holdover aiming instead of adjusting the turrets.

 

[howardhuges]

Good scopes cost $$$$. Leopold , USA made stands by their scopes and will fix or replace them quick. Folks will spend $2000.00 on a rifle but balk at a $500.00 scope...which is about the low end price for good optics. Me... I would send it back, and when returned sell it and chalk it up as Education at the University of life and buy something better. The ar15 forum has a section for new and used optics...some very good deals there.

 

[Capona]

Howard is spot on. Search on buy once, cry once. It's a common topic.

Many people would say the price of the scope should start at 1/2 the price of the rifle as a general rule.
For the m1a, it's tough on scopes and I'd go better than the rule if you can.

However I've never had issues with my Leupold vx3 that I paid $500 for.

It's always been on zero.

But my Nightforce nxs which cost $2000 is a much easier and enjoyable scope to use. Plus it doubles for a fine club that will return to zero.

 

[Doc]

+1 for Nightforce
Unlike Capona, I have had trouble with Leupold_ I do not know how good the new Leupolds are, they may be great - when I (and my brother) had problems with several of them many years ago---- well I just quit Leupold...

 

[Freshman]

Definitely aware that this is not one of the better scopes on the market... I had originally purchased the rifle for shooting high power. When I left New Mexico, I no longer had ranges near me that held high power matches, so I decided to throw an optic on top. At that point, my financial situation had changed, and I was unable to afford a nicer scope. All that being said, I now find myself in a position where I can possibly justify spending a decent amount on an upgrade. We're not talking U.S. Optics, but definitely a step up from the budget Nikon series. I suppose the question I should be asking is: do you guys find it better to shoot with holdovers, or to make adjustments? The loads I developed for this rifle are very low powered. I give around 18 minutes of elevation at 400 yards with 175gr SMKs.

 

[Bamban]

Not only you dealing with scope issue, the mount is another factor. I was verifying my M1A 600 yard load with scope at 600 at one time using my NXS, and I could not group for crap, pulled out the scope assembly, shot a sub minute group with irons on the MR target. Put the scope back on my 300 WM Arctic Warfare, went back to the knob settings and shot a sub half minute group. The scope was fine. The mount, unfortunately one of the favorites here, was never used again.

 

[Capona]

Never heard of that mount ever.
There are only 3-4 mounts to be used on the m1a.

Not only you dealing with scope issue, the mount is another factor. I was verifying my M1A 600 yard load with scope at 600 at one time using my NXS, and I could not group for crap, pulled out the scope assembly, shot a sub minute group with irons on the MR target. Put the scope back on my 300 WM Arctic Warfare, went back to the knob settings and shot a sub half minute group. The scope was fine. The mount, unfortunately one of the favorites here, was never used again.

 

[KurtC]

Definitely aware that this is not one of the better scopes on the market... I had originally purchased the rifle for shooting high power. When I left New Mexico, I no longer had ranges near me that held high power matches, so I decided to throw an optic on top. At that point, my financial situation had changed, and I was unable to afford a nicer scope. All that being said, I now find myself in a position where I can possibly justify spending a decent amount on an upgrade. We're not talking U.S. Optics, but definitely a step up from the budget Nikon series. I suppose the question I should be asking is: do you guys find it better to shoot with holdovers, or to make adjustments? The loads I developed for this rifle are very low powered. I give around 18 minutes of elevation at 400 yards with 175gr SMKs.

If your scope of choice has turret caps, it was not designed to make adjustments after it is zeroed. Many of these will have BDC reticles for use at longer ranges, you just need to make sure the marks match your trajectory at the appropriate ranges.

Scopes designed for constant range adjustments will have exposed turret knobs. These will have either a standard reticle or one with dots that can be used for range estimation. Leupold offers a Custom Dial Service for a low price. They can give you a elevation dial custom marked for you your trajectory. These will fit just about any of their current production scopes, even some of the lower priced ones.

 

[Capona]

I didn't know this, I learned something today and it's not even noon yet.
Thanks Kurt.

If your scope of choice has turret caps, it was not designed to make adjustments after it is zeroed. Many of these will have BDC reticles for use at longer ranges, you just need to make sure the marks match your trajectory at the appropriate ranges.

Scopes designed for constant range adjustments will have exposed turret knobs. These will have either a standard reticle or one with dots that can be used for range estimation. Leupold offers a Custom Dial Service for a low price. They can give you a elevation dial custom marked for you your trajectory. These will fit just about any of their current production scopes, even some of the lower priced ones.

 

[howardhuges]

OH MY GOODNESS...SCOPE MOUNTS ARE EVIL ON THE M14 SYSTEM. As I posted before I have had NOTHING BUT BAD with scope mounts on this weapon platform... tried ARMS and Smith mounts...all would shoot loose even with Blue goo...Hard as heck to install...I gave up...this is on a LRB and a 93K SAInc rifles. The 308 AR Platform is the bomb for optics... install, "0" the optics....shoot all day.

 

[M1A's r BEST]

I bought a single screw scope mount/rings for my M1A back in 1979. No idea who made it. Aluminum, large thumb screw, three steel rods embedded in the aluminum to match up to the slots in the M1A receiver. Never any issues with it. Changed the scope a couple times over the years but finally went back to my old Bushnell 4X12 with the BDC turret. One of the guys here told me some of those old Bushnell scopes were really good scopes though. A new one cost me $75 at Best Buy in Arlington, VA in 1979. A used one last winter cost me $200. That one will go on my son's M14S pretty soon.

Had fun with it. Deer hunted with it. Went to an Appleseed and an RBC with it. Thousands of round through it over the years.

The plastic cap screw on the BDC turret did break a few years back (split after about 30 years). I found a screw/bolt in my tool box at the truck that had the same threads. I enlarged the hole in the plastic cap, put some black formagasket on the bolt threads, stuck the plastic cap down over the bolt threads and screw the bolt into the scope turret. Been holding fine.

I do not routinely remove the scope mount. It's only been over four or five times over the years. Why take it off?

Guess I got lucky.

 

[Puccini]

I was also instructed that whenever you change scope adjustments you always finish your adjustment from the same direction.

For instance:
If your shooting at 300m and you want to re-adjust for 100m, you lower the scope value adjustment LOWER THAN the 100m setting and then adjust BACK UP to the proper 100m setting. The same if your going the other way. If you over adjust for 300m, go lower so that your final adjustment will be in the UP direction.

I don't usually do that so I am not sure of this suggestion but I have had other shooters tell me it is correct.

 

[nf1e]

Mount, rings and scope make all the difference in the world.
You can't beat a rifle that has the mount machined with the receiver for stability.

[URL=http://s1180.photobucket.com/user/nf1e/media/IMG_0498_zpsamcy5fxl.jpg.html][/URL]

 

[Freshman]

Fairly certain the mount is not my issue; otherwise I would be seeing much larger groups. I also machined the mount to fit my receiver specifically.

Lots of good info here. Thanks for the help guys. I have another project in the works now, so I will likely be keeping the scope on the rifle for the time being. The difference being, I will now be using the mil-dots as holdovers instead of cranking on the knobs. In the long run, I suppose it will be better to practice this.

Thanks again.