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Discussion Starter #1
A while back I purchased an Armscorp-receivered M14 off of Gunbroker with minimal information from a less-than-informed seller. Basically, I rolled the dice and took my chances. What I wound up with is an Armscorp receiver that is a bit out of spec in a few areas and what appears to me a medium-heavy Douglas match barrel. I added an ARMS #18 scope mount, Leupold PRW rings, an old Redfield scope I had laying around and went to the range. The good news is that this rifle is ACCURATE! GI3 The bad news is that because the receiver is out of spec, I don't have enough windage adjustment to zero the rifle. How out of spec is it? Well, with the scope windage cranked all the way against the left-hand stop, I was STILL shooting a foot right at 25 yards. Burris offset rings are inbound to correct that, but that wasn't the point of this post. The real point is that with a scope mounted, this beast tips the scale at 12.25 pounds, unloaded! Is it possible to turn the barrel diameter down to USGI specs to shave some weight, or do I risk losing the accuracy this barrel appears to be graced with? I also have an idea floating around in the back of my mind to buy a Rock-Ola receiver and have this rifle rebuilt to get away from the current out of spec Armscorp. Crazy? Maybe.....
 

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It would be counter productive. It would cost less to replace the BBL with a Criterion or JRA ect. Also turning down the heavy barrel could alter the harmonics of the barrel making it less accurate IMHO. BTW I built many Armscorp guns back in the day although we never thought of scoping them back then. They shot great with Irons.
 

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You should consider moving the front sight post before you do anything crazy or costly. The distance you have to move it to correct should be very minimal
 

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I believe his issue is scope mounting related. I would look at figuring out how to tweak the mount to fit correctly. What areas on receiver are out of spec? As far as losing weight goes. Get a new barrel. Run a better chance of trading accuracy by turning it as mentioned. What stock is it in? There is no easy to make these things feather weight. If you want light semi 308, look at the dpms g2 series.
 

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Have you shot it with the irons? how did it do? if the front sight is centered and rear is centered and it shoots fairly straight, that narrows it to scope or mount. good luck!
 

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I had the same issue when I scoped my Norinco m14, it had shot well on Irons and when I put glass on it I got good groups but I could not adjust them closer than 6 inches left of the point of aim. It turns out the Scope mount was was misaligned and I needed to play around with it a little more. Turned out to be an easy fix but a hard diagnosis. In the end I needed a laser bore sight and some fiddly tweeking to figure it out and get her eyes facing the same way as her nose. If you have not already you could look at doing the same.

As for the weight, that does not seem that terrible. Mine is 5.2kg (11.4lbs) unloaded after adding the mount, scope, bi-pod, cheek rest and suppressor. And I would happily carry an extra pound if it meant improved accuracy. How much do you think you would be able to trim off your current total?
 

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you could maybe have the barrel fluted and refinished to lessen its weight a bit, but turning it down completely would be to costly to justify. Unless I am misunderstanding what I read, turning down a barrel that has already been heat treated and stress relieved is not a good idea and could be dangerous if not re-treated and relieved. That would be VERY expensive. I suggest getting some trigger time behind what you have now and if weight is still a problem for you, then look into buying a new barrel. A match grade 18" in G.I. profile would be my suggestion for a "light weight" M14 barrel.

I did not think I would care for my medium barreled setup, but I do not really notice the extra weight when I am shooting, plus it is more accurate and handles more rounds before any stringing from heating up. The added weight actually helps me when shooting off-hand, so I have come to really like the medium barrel that I thought I would hate. Try yours for a while and then decide. If you like it, you could buy more ammo with the money you would have spent on the new barrel and install.
 

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I would find one of the smiths that do custom fluting. I have seen some aggressive flute jobs.

Those are all on ars I have not seen many barrels that have been reprofiled.

Jon Wolfe is who you need to talk to. He is trusted and I know for a fact he does provides custom barrel profiles.

I bet he could tell you if it's a bad idea to re profile a finished m14 match barrell. It would not surprise me if it's a nono.
 

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1 foot right at 25 yards? I'm surprised you're able to get an idea of its accuracy at longer ranges being that far off.
 

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Discussion Starter #10 (Edited)
It shot one foot right at 25 yards with the scope, but shoots to point of aim with the iron sights centered. With the irons, my best five shot group of the day was 1.2", center to center at 100 yards. At 25 yards, with the scope, it would put three shots into one one hole. Needless to say, I am eager to see what it will do at distance with a properly centered scope!
 

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Look at how the mount interfaces with the receiver. Your problem most likely lies within that area. I'm thinking that either the bolt mounting hole, lug recess, or the clip mount area are crooked. May be as simple as the rear groove isn't machined deep enough. Have you tried a different scope?
 

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Discussion Starter #12
Look at how the mount interfaces with the receiver. Your problem most likely lies within that area. I'm thinking that either the bolt mounting hole, lug recess, or the clip mount area are crooked. May be as simple as the rear groove isn't machined deep enough. Have you tried a different scope?
I have a new Leupold inbound. I will start doing the process of elimination when it arrives. I see where a laser bore sighter could come in very handy here......
 

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It sounds like this rifle only has scope mount issues which can be easily fixed by either tweaking the mount or using rings with offset inserts.

On turning the barrel down, I do not recommend it. Any time a button riffled barrel is altered in contour it needs to be re-heat treated for stress relief. Failure to do this can result in a catastrophic failure of the barrel even when shooting standard loads.
 

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Turning down a barrel will not induce sufficient stress to require a stress relief; if the cuts are kept to .050" or less. Krieger's Engineer recommended this number, but I cut that number in half when I flute or turn down barrels. I rarely exceed .020" cuts.

However, if the barrel has existing stress and has not be properly relieved from the outset, the removal of material could be detrimental.

On a side note, I don't like to turn down barrels or alter contours, it's a lot of work and one-off machine work is very time consuming. The fact remains in can be done, but it is not a first option.

In your case, to address the OPs weight concern, turning it down to standard contour specs would not be recommended. I would suggest a hybrid between standard and medium. You could probably shave 1/2 pound this way.

A better option would be to sell the heavy barrel; if it's in good shape, it would cover some of the expense of a new barrel of your choice.

The scope alignment issue is probably related to the receiver being incorrectly machined. Sometimes the scope rail can be relieved on the mount to achieve better alignment.
 

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J, Tell that to the fellow who's M1A blew up in Reno several years ago and to one of my National Guard shooters who experienced the same failure during the Wilson matches while shooting his personal rifle. It's almost a common occurrence. I know of at least 10 instances.
 

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I'm not sure I'm drawing the correlation? As long as good machining practices are followed, i.e. depth of cut, feed and speed rates, etc., there is certainly no inherent danger with the exception being improperly stress relieved barrels at the outset and not leaving enough material outside the wall of the bore.
 

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The bad news is that because the receiver is out of spec, I don't have enough windage adjustment to zero the rifle.
Buy a scope with more adjustment. The SWFA scopes have like 120mins of adjustment, my loopie M3 has like 84MOA, the bushnell 10x cheapy has 80+, my IOR 10X had 110 etc. Also M1A scope mounts are a PITA to put on so it's very likely that you didn't do it 100% right or that it could be stand to be fitted a little bit.

Do not turn down that barrel. What you should do is get a lighter profile barrel and have it installed then sell the douglas. You can get a criterion USGI type for what, 250? The barrel you have is probably worth that. So just eat the cost of having a smith swap them, I think Fulton charges 75$ if you buy the barrel from them.
 

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Most rifling processes, with the exception of cut rifling, impart certain stresses in the barrel steel. These are normally mitigated by heat treating or sometimes using a cyro process. Even so, there are stress patterns in the steel. Machining the contour of one of these barrels induces changes to the stress patterns. Stress relieving normalizes the barrel which increases it's strength and resistance to pressure failure in weak spots that are created by altering it's contour.

In the case of M14 barrels, there were nine failures to barrels turned to medium contour from blanks used in a Marine Corps contract. These barrels were left over from the run so the Marines didn't get the ones that failed. Those that did were originally purchased in the white and did not have splines or threads. The barrels were finish machined and sold without being stress relieved. There were some 35 barrels involved.

Another documented case involved a Winchester Model 70 heavy match barrel that was turned down to a heavy pattern M14 barrel. Winchester barrels are hammer forged. This barrel was not stress relieved after turning down and the result was a catastrophic failure after about 1200 rounds. I personally inspected this barrel and the resulting damage. The cartridge case did not show any signs of excessive pressure.

The barrels in these accidents usually split in about three places from the receiver to the op rod guide. Often the receivers ended up in three or four pieces (they were all cast M1A receivers). Bolts usually survived in tact, but I wouldn't recommend reusing them.

Note that these barrels usually shot quite well for 1200 to 1800 rounds and failed using both hand loaded and factory ammunition. The Wilson Matches rifle was shooting M118 and failed during the first stage 200 yard standing match. I have that barrel in my collection.
 
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