[NoExpert]

It's probably the mount. SA Inc. hasn't made a good mount for some time now. Try a Bassett mount, since the mount is easy on/off I'd say get the low picatinny mount. I know, my solution probably isn't what you want to hear, but it's realistic. Before you install the Bassett, make sure both the screw and hole threads are clean and dry, acetone is good for cleaning both.

 

[Al Mack]

Both solutions are good. Get another rifle and a Basset mount. You'll be all smiles.

 

[Navy Horn 16]

Why are there so many problematic fluctuations here? ...... It is pretty irritating to get an expensive Zeiss scope, only to have these kinds of issues. I have removed the scope and mount from the rifle and I now use iron sights for the time being, but I am seriously toying with the idea of saving some money and getting a properly built M14 from Fulton Armory or LRB (I would just keep my Stanard M1A for blasting around with cheaper ammunition and iron sights).

It's called a "single point of failure" and in this case it's your mount, and to a degree your expectations of the rifle.

Get a quality mount like the NATO standard ARMS #18 (I don't have any experience with the Bassett, but I have no reason to doubt it) get it properly secured to the rifle and leave it alone. Those "jack of all trades" mounts that allow you to squint and try to use your irons with a scope on the rifle are crap.

Guys who shoot for a living don't ask their battle rifles to be both CQB setups and long range rifles. They have squads with equipment and training to accomplish a mission. If you want a 7.62 rifle setup for short range iron sight shooting, then the M1A can be that rifle. If you want a precision long range scoped rifle, the M1A/M-14 can be that rifle too, if you properly gear it up.

Having a nice rifle and an expensive scope and crappy results isn't the rifle's fault. Fix the weak link.

 

[bigbang]

7.62 spark, I have had the same issues with my SAI gun and arms #18 mount. Ran out of windage adjustment. Put on windage adjustable rings from EAW and centered the reticle. But accuracy was still mediocre. Then the expensive part starts. EBR stock, trigger job, arms #36-S-EX-AR10 rail installed by a prof gunsmith. After 1 year and 2.000,- € I am satisfied at last.
Wolf

 

[3/17]

I have had the same problems with my SAI too with the ARMS #18 mount. Ran out of adjustment windage wise and almost on the elevation. 1st sighted in at 25 and then 100 was worse. Thought it was the scope but that works fine on the flattop AR. I followed the directions for the mount. Remounted and made sure ebverything was tight. Also used a Sadflak mounting bolt after I shortened it. Didn't make much of a difference.
My rifle was sent back to replace the bolt and they ended up replacing the std NM weight barrel to med weightNM bbl. Could be that when they put on the barrel that it may be off just a bit to one side. I don't remember having the problem with my old barrel when I had a SEI mount. I'll try one more time.

 

[daveboy]

I've only had my SAI for a few months. I read all I could concerning scope mounts and could find very little if any good reviews on the Springfield mounts. So, I installed a Basset on mine. I ran out of windage adjustment before I could zero the scope. Remounted and retightened everything and had same problem only it might be in the other direction. I replaced the aluminum rings I had with some quality steel Weaver rings. Problem solved!

My advice...Ditch the Springfield mount. Install a Basset mount with some good rings. Apply some locktite and tighten it all down.

daveboy

 

[RAMMAC]

Hmmm, I have a Loaded model that I put a Sadlak Airborne on (I installed it as per their instructions) and then I slapped an inexpensive Millett LRS scope on it, I get sub MOA out to 200 yards with my hand loads. My total investment of money and time seems to have been way less than either the SA mount or ARMS mount options.

 

[slimj]

The 4th Gen Steel Mount is made to about the same specs as a SADLAK or Smith Enterprise mount. I think the biggest issue with these mounts is that people have a hard time reading the instructions. If its canting off to the right theres a good chance you are cranking the front contact screw down too far which will cause the mount to flex. My advice. Take the mount back off and then carefully follow the instructions and reinstall it.

To prevent it from coming loose you need to make sure the cam has pressure against the reciever bolt after the reciever bolt is finger tight. Then tighten the reciever bolt down a good 1/4 turn or so.

 

[RightHand]

There are significant differences between the SAI Gen 4 scope mount and either the Sadlak or SEI mounts one of which is the absence of the key on the mount that mates with the groove on the receiver, a critical factor in a solid mounting system.

 

[RAMMAC]

I did a search on this forum and found several conversations about the Gen 4 mount and a lot of comments on what was right or wrong with them.

I've never even touched one so I have no personal experience with the mount but I can say that after reading what others have had problems with I suspect that you might improve the performance by installing the the mount with careful attention to several details.

Evidently there are two mounts, an aluminum earlier model that had a small horizontal guide machined in to the mount design (on the inside face that contacts the left side of the receiver) and a steel mount that had that portion of the mount machined away (SA determined it wasn't necessary). It sounds like the steel mount is the one that has a lot of problems, no surprise there since they removed that horizontal guide. Without the guide the process of how you tighten the mounting screws becomes premier in how to get the mount to align with the center line of the bore. All mounts work better when you follow a specific process in regards to the order and technique for tightening the screws but the Gen 4 seems to be very sensitive about this issue.

The key for me has always been to ensure that the mount's center line is parallel to the bore's center line, both vertically and horizontally. If that relationship is off you can't expect the scope's adjustments to be able to compensate. What you use to determine the alignment of the mount varies with each type and the tools you have available but the idea is to place something very long on the top and along the side of the mount (after you have installed it) that is centered and in alignment with the mount's long axis and use that thing as a reference to compare the relationship between the center line of the mount to the center line of the bore. What ever you use should be about as long as the barrel so that the end is about even with the front sight.

First lay, lets call it a reference rod or just a rod, the rod on the top of the mount. Make sure it is in line with the center line of the mount. The distance between your reference rod and the top of the barrel should be the same along the entire length of the barrel. Then you perform the same comparison but with the reference rod on the side of the mount.

If your reference rod is closer at the front sight than at the back of the receiver then the mount is canted down and vice versa. The same idea applies to when you check the alignment from the side only you are looking for the left/right alignment.

If either is out of alignment then you have to figure out a way to fix the problem, usually tightening the screws in a particular way and wiggling the mount to get it center on the screws as you go along will help. The screws should be tightened a little at a time, do not tighten any one of the screws all the way down in one step, the idea is to tighten them down slowly and check those alignments with your reference rod as you go along. This way you can find which screw seems to cause the misalignment, if it exists. There is one gun smith (Art Lupino) on the this forum that likes to create a gasket out of JB weld other bedding material that is between the mount and the side of the receiver. This helps to eliminate any movement and most likely helps keep the zero of the system if you have to remove and re-install the mount.

The final possibility is that even if everything is aligned correctly and tightened to proper specs (you really need to use a torque wrench to get this right) you can have issues with the mount shifting under recoil. Not much I can say here but sometimes you can mitigate shifting problems with shims or modifications but most often it is an issue of poor design or improper installation procedures.

 

[NoExpert]

I would definitely recommend a Sadlak mount, however buying one is up to the OP's budget.

 

[Gman56]

Try a basset mount easy install and take off 10 sec dont use locktite with it! I have a basset high mount it has never came loose!

 

[7.62Spark]

The 4th Gen Steel Mount is made to about the same specs as a SADLAK or Smith Enterprise mount. I think the biggest issue with these mounts is that people have a hard time reading the instructions. If its canting off to the right theres a good chance you are cranking the front contact screw down too far which will cause the mount to flex. My advice. Take the mount back off and then carefully follow the instructions and reinstall it.

To prevent it from coming loose you need to make sure the cam has pressure against the reciever bolt after the reciever bolt is finger tight. Then tighten the reciever bolt down a good 1/4 turn or so.

I have read the instructions every time I have mounted this scope, and I have had these various problems every single time. I think this quote points something interesting out:

There are significant differences between the SAI Gen 4 scope mount and either the Sadlak or SEI mounts one of which is the absence of the key on the mount that mates with the groove on the receiver, a critical factor in a solid mounting system.

I have noticed this (the instructions simply say to make sure that the bottom left part of the mount does not contact the stock, nothing more, nothing less), and it could definitely be an issue, now that you mention it. Essentially, I have had to "eyeball" things here, so there could definitely be some inconsistency in the way I have mounted the scope (again, I don't know what the Sadlak instructions say, but the Springfield instructions say very little).

I did a search on this forum and found several conversations about the Gen 4 mount and a lot of comments on what was right or wrong with them.

I've never even touched one so I have no personal experience with the mount but I can say that after reading what others have had problems with I suspect that you might improve the performance by installing the the mount with careful attention to several details.

Evidently there are two mounts, an aluminum earlier model that had a small horizontal guide machined in to the mount design (on the inside face that contacts the left side of the receiver) and a steel mount that had that portion of the mount machined away (SA determined it wasn't necessary). It sounds like the steel mount is the one that has a lot of problems, no surprise there since they removed that horizontal guide. Without the guide the process of how you tighten the mounting screws becomes premier in how to get the mount to align with the center line of the bore. All mounts work better when you follow a specific process in regards to the order and technique for tightening the screws but the Gen 4 seems to be very sensitive about this issue.

The key for me has always been to ensure that the mount's center line is parallel to the bore's center line, both vertically and horizontally. If that relationship is off you can't expect the scope's adjustments to be able to compensate. What you use to determine the alignment of the mount varies with each type and the tools you have available but the idea is to place something very long on the top and along the side of the mount (after you have installed it) that is centered and in alignment with the mount's long axis and use that thing as a reference to compare the relationship between the center line of the mount to the center line of the bore. What ever you use should be about as long as the barrel so that the end is about even with the front sight.

First lay, lets call it a reference rod or just a rod, the rod on the top of the mount. Make sure it is in line with the center line of the mount. The distance between your reference rod and the top of the barrel should be the same along the entire length of the barrel. Then you perform the same comparison but with the reference rod on the side of the mount.

If your reference rod is closer at the front sight than at the back of the receiver then the mount is canted down and vice versa. The same idea applies to when you check the alignment from the side only you are looking for the left/right alignment.

If either is out of alignment then you have to figure out a way to fix the problem, usually tightening the screws in a particular way and wiggling the mount to get it center on the screws as you go along will help. The screws should be tightened a little at a time, do not tighten any one of the screws all the way down in one step, the idea is to tighten them down slowly and check those alignments with your reference rod as you go along. This way you can find which screw seems to cause the misalignment, if it exists. There is one gun smith (Art Lupino) on the this forum that likes to create a gasket out of JB weld other bedding material that is between the mount and the side of the receiver. This helps to eliminate any movement and most likely helps keep the zero of the system if you have to remove and re-install the mount.

The final possibility is that even if everything is aligned correctly and tightened to proper specs (you really need to use a torque wrench to get this right) you can have issues with the mount shifting under recoil. Not much I can say here but sometimes you can mitigate shifting problems with shims or modifications but most often it is an issue of poor design or improper installation procedures.

Yes, my Gen 4 mount is the steel one. Based on what you have told me, there could be quite a few issues I have been having here. Of course, narrowing such things down would take some time.

I would definitely recommend a Sadlak mount, however buying one is up to the OP's budget.

That would be a helluva lot cheaper than buying a Fulton or LRB gun. Of course, it would be nice to have a higher end M14 someday, but if I could get a better mount, I could still use this rifle for practice with a scope. I will have to consider my options, but getting a better mount of some sort is more appealing than all kinds of trial and error crap with Springfield's mounts (perhaps is is theoretically possible to make it work, but after two trips to a gunsmith and multiple attempts of my own, I think I will look for an ARMS, Sadlak, Basset, or some other sort of mount).

 

[NoExpert]

If you want a primarily scoped platform go with the Sadlak, if you want to switch a lot or use irons a lot go with the Bassett. I mainly recommend Sadlak because they'll do whatever they can to get you a mount that goes on your rifle correctly without a gunsmith having to fool with it.

Of course the mount is only as good as the rings so definitely use decent rings made for picatinny rails.

 

[7.62Spark]

If you want a primarily scoped platform go with the Sadlak, if you want to switch a lot or use irons a lot go with the Bassett. I mainly recommend Sadlak because they'll do whatever they can to get you a mount that goes on your rifle correctly without a gunsmith having to fool with it.

Of course the mount is only as good as the rings so definitely use decent rings made for picatinny rails.

I will have to think a bit about this, but I have heard that Sadlak can send one some sort of measurement kit to help compensate for the out-of-spec receivers found on M1A's. I may go with the Basset, as I do like to use the irons every now and then. Of course, I am open to other ideas, and the Sadlak also seems appealing.

I have one inch Zeiss Victory scope rings (I have set of low rings and a set of high rings). They seem to fit well on the Gen 4 Springfield scope mount. I am assuming they will fit well on other scope mounts.

 

[RightHand]

Our Sadlak Online Library includes a variety of information that can be printed as well as viewed. These include scope mount installation instructions and mounting diagrams, tutorials for using the receiver inspection kit and removing the stripper clip guide as well as an assortment of information that might be useful for the M14/M1A owner.

Give us a call if you have any questions that may not be answer or if you have a problem you would like to discuss

Sadlak Online Library

 

[Ivan1GFP]

I know I have posted this before, so if you have already seen this, please ignore.

There are some receivers that don't have the slots aligned correctly. I had a Armscorp M14 that had the horizontal slot fairly far off. I don't own that rifle any more. I had another Armscorp that had the horizontal slot correct. I don't own that rifle any more either. (Shoulda kept it but it had other problems.)

My mount of choice from many years back is a B-Square. It has no keys at all but uses two large STEEL set screws that fit against the receiver web on the left side. They can be adjusted to change elevation. I adjust them with slight tension as the attachment knob (yes, knob, not knobS) is tightened. Some of the mounts come with brass tipped screws but those brass tips will peen and the mount gets loose. I replaced them with the steel tipped version.

This mount lets me put in 20 MOA or whaever it takes for me to sight in my telescope with plenty of adjustment remaining to in theory get out to 1000 yards from a 100 yard zero. On one Leupold 6.5-20 EFR, I had about 54 MOA of elevation remaining after zeroing at 100 yards.

I also use Millett Angle-Loc rings to make slight windage corrections when zeroing to leave the telescope's internal adjustments as centered as possible.

The mount is a bit high to allow the use of iron sights even when installed. The attachment knobs for this mount are a bit soft, but after stripping a couple, I just put a white index mark with a dash of paint on the knob and the receiver. That prevents me from over tightening and it also lets me tell if the mount is shooting loose which it does not.

This setup is good enough for repeatability in that I have removed and re-attached the scope between each shot and still been able to hold sub-MOA.

The key trick on this mount is the slight tension. It makes for repeatability.

YMMV, but this works for me.
- Ivan.

 

[XSabers]

Both my son and his college room mate (now about half way through BUDS) have Basset Low Picatinny mounts on their rifles. When I went to the range with them the room mate put his scope back on his M1A after having it off for a couple months. He followed the mounting directions and when he fired his first group he was about 1 inch off of his zero. After I saw how well they worked I just ordered one.

 

[kopterdoc]

Hmmmmm interesting I have had an ARMS 18 old style mount for years on my 1995 built SAI sm M1A and put a SN-3 US optics on top with no issues at all. Lock-tited the bolt after applying 60 " lbs. of TQ as per instructions. Guess I may have got lucky on the geometry.