The M14 Barrel
Probably the one most important part required for good accuracy is the barrel. M14 barrels are not made by many companies. They all make blanks, but only a few actually are producing ready to install M14 barrels. Krieger, Barnett, Wilson, and Criterion are the only ones I am aware of right now.
The M14 barrel is not all that easy to make. Every machining step is timed off of the gas port which is supposed to be drilled in one of the grooves. Of course, the groove is on the inside of the bore making the location difficult to pin point. Some don’t think this step is necessary, but serious barrel makers do. All dimensions are located in relation to the gas port. All thread timing and the splines for the gas cylinder and flash suppressor are machined in relation to the gas port. This is probably why most barrel makers don’t want to deal with making M14 barrels.
AR15 barrels are much simpler! Those that do make M14 barrels however, can barely keep up with the demand. Krieger did a major plant expansion to help keep up.
Back in the early 1980’s I was introduced to the excellent barrels made by Gene Barnett. Our National Guard Shooting Team was invited to try out a half dozen of Barnett’s heavy match barrels on our NM M14’s. These came through the “system” and I think all of the State NG teams were issued some of these barrels. Gene also made barrels for the USMC and USAF. We were able to acquire some of them prior to this through Champion’s Choice, Inc. and I had installed a few on my customers rifles. What a difference a heavy barrel makes! The wimpy standard NM barrels we were used too simply would not shoot against the heavy Barnett barrels. I’m sure that is why the Guard decided to try them. Civilian shooters were making life difficult for the military teams. The only problem we had was getting ammunition that would shoot well in the heavy barrels. Our Barnett barrels were 1:12” twist six groove rifling. I found the twist didn’t matter all that much, but the number of grooves did! We were issued Lake City M118 ammunition. I mention this because the civilians, who were cleaning our clocks, were shooting hand loads. Barnett’s six groove barrels love Sierra Match King Bullets! Sierra doesn’t make M118 bullets… A typical Guard M14 would shoot 1 ½ inch groups with M118 out of a six groove barrel. The same gun would shoot under an inch with Sierra 168 grain Match King bullets! Well under! It has something to do with the thickness of the bullet jacket and the depth of the rifling grooves. Sierra bullets had thinner jackets. That’s when we discovered “Mexican Match” ammunition. We just pulled the bullets from our M118 and installed the 168 gr. SMK. About this time, the military started issuing XM852 Special Match which cured all our problems. Barnett still makes these great barrels and they can be had in four groove as well. The four groove seems to shoot about anything.
In the mid 1980’s I discovered Krieger Barrels. They were advertised in the Shot Gun News as being Match Grade and Quality, stainless steel with short chambers. I never heard of Krieger, but I wanted to try just about anything new and I ordered one for my new M14 match rifle. About the same time I purchased a couple of Smith Enterprise’ receivers to try. This turned out to be a great combination. The McMillan stock helped too! Krieger offered SS or chrome molly in 10, 11, and 12 twist, four groove rifling. This is much the same as they offer today. These barrels would shoot ½ inch! Yea for gas guns!
There was also Obermier, Snyder, Schillen, and others, but they did not produce a finished M14 barrel like Barnett and Krieger.
I want to make one thing clear. There are many excellent barrel makers around the country. They all shoot good, but most require custom machining so I am not including them here.
Recently, Wilson Barrels and Criterion Barrels have been available. Wilson has been around for quite awhile and they have an excellent reputation for match grade AR15 barrels. Most AR manufactures use Wilson Barrels. The junior rifle team I help coach has set some 35 National Team and Individual Records, many of them with Wilson Barrels. Right now they are making standard M14 barrels in chrome lined or plain. They are also making some match grade barrels and will soon have medium weight NM barrels on the market.
Criterion is making a similar selection of barrels for the M14. I have installed a couple of the Criterion medium weight SS match barrels on rifles for LRB Arms and I found they shoot very well. The rifling looked smooth as glass too.
Over the years, I have come to prefer 1:10” twist 4 groove barrels for my match rifles. This combination seems to shoot anything well and will shoot the good old M118 Match ammo too!
I found that GI National Match barrels can be good, but they are hard to find in new condition and usually do not shoot as well as commercial match barrels. The medium weight NM barrels produced in 1982-83 were the best of the GI barrels and I think Saco-Lowell probably was the best producer. The standard weight NM barrels are too thin, hence not stiff enough. I see Krieger is now making a standard weight match barrel. It should be an improvement over the GI NM barrel, but it’s still not heavy enough to stand up to the fat barrels. Krieger’s DMR barrel is pretty good and ½ pound lighter than the heavy barrel. The only thing I don’t care for in the DMR barrel is the 1:12” twist (not that it is much of a handicap).
While I’m on the subject of barrels, how many of you have put your eyeball in the breach end and really looked at the throat. A throat gage can tell you the relative amount of erosion, but many times your eye is a much better indicator of the real condition of the throat. I’ve seen dozens and dozens of GI barrels that have chrome plating flaking off in the barrel throat. They often gage two or three, which is normally OK, but the actual condition says it should be replaced. This is very common in GI chrome lined barrels. Almost all GI barrels being sold are used and many are well used. Always look!
I had a Krieger on one of my rifles that measured 3.5 TE. I thought that was probably good to go until I was looking in the chamber with a chamber inspection mirror. There were craters the size of pot holes in the New Jersey Turnpike in the start of the grooves! I thought “this can’t be good”… That was when I changed the barrel. It had 6850 rounds through it. Always look. Only 3.5 TE….
Bluesteelnwood asked about the differences on how the Army and Navy built rifles. It is interesting so I am repeating the thread here.
It goes back to the days of the M1NM rifle. One of the differences was the Navy/Marine Corps would epoxy the hand guards to the barrel. This worked OK, but one had to destroy the hand guards to remove them or make a barrel change. Army style was to glue and screw the upper hand guard to the lower band with the liner removed and ream the front ferrule so it didn't touch the barrel. The lower hand guard was shortened so it would not touch the receiver and epoxy to the lower band. The only problem with this is the operator would have to use some caution when handling the rifle by the upper hand guard so it wouldn't break loose. The Navy also would often free float the barrel by cutting away part of the ferrule and lower band. Sometimes this works OK and sometimes not. The Army would always bed a rifle with pressure on the ferrule/lower band to stabilize the barrel. This system almost always works well.
There are several differences in the way the Army and Navy build M14 rifles.
They both unitize the gas cylinder and barrel band. The Navy welds and the Army screws them together. Both systems work, but I have seen the welds break during competitions and the accuracy goes down the tubes. I have seen a couple of Army gas cylinder shoot the screw loose, but it is easy to tighten them on the spot. Problem solved. When properly epoxy and staked, the screws almost never shoot loose. One thing the Marines did with many (not all) M14 team rifles was welding lugs on the receiver. This really worked well and they did both rear lug and double lug guns. The Army MTU claims they didn't do lugs, but I know they did on some of their guns. The Marines would free float the barrels when bedding and the Army would pressure bed them. The only problem with lug guns is sometimes the weld would break on the lugs.
This results in a big drop in accuracy! Commercial receivers with lugs installed by the factory rarely if ever fail because the receivers are heat treated after the lugs are welded on. I should also note that free floating didn't always work. Both services would rebuild a rifle till it would shoot within standards however. One thing I liked about Marine M14's is that many of their team rifles were equipped with McMillan stocks. The Army always seemed to stick with wood. There are some other minor differences, but these are some of the main ones I know of. Both services built outstanding NM rifles. I was trained to do it the Army way.
By Ted Brown (Shooters Den)
The M14 barrel is not all that easy to make. Every machining step is timed off of the gas port which is supposed to be drilled in one of the grooves. Of course, the groove is on the inside of the bore making the location difficult to pin point. Some don’t think this step is necessary, but serious barrel makers do. All dimensions are located in relation to the gas port. All thread timing and the splines for the gas cylinder and flash suppressor are machined in relation to the gas port. This is probably why most barrel makers don’t want to deal with making M14 barrels.
AR15 barrels are much simpler! Those that do make M14 barrels however, can barely keep up with the demand. Krieger did a major plant expansion to help keep up.
Back in the early 1980’s I was introduced to the excellent barrels made by Gene Barnett. Our National Guard Shooting Team was invited to try out a half dozen of Barnett’s heavy match barrels on our NM M14’s. These came through the “system” and I think all of the State NG teams were issued some of these barrels. Gene also made barrels for the USMC and USAF. We were able to acquire some of them prior to this through Champion’s Choice, Inc. and I had installed a few on my customers rifles. What a difference a heavy barrel makes! The wimpy standard NM barrels we were used too simply would not shoot against the heavy Barnett barrels. I’m sure that is why the Guard decided to try them. Civilian shooters were making life difficult for the military teams. The only problem we had was getting ammunition that would shoot well in the heavy barrels. Our Barnett barrels were 1:12” twist six groove rifling. I found the twist didn’t matter all that much, but the number of grooves did! We were issued Lake City M118 ammunition. I mention this because the civilians, who were cleaning our clocks, were shooting hand loads. Barnett’s six groove barrels love Sierra Match King Bullets! Sierra doesn’t make M118 bullets… A typical Guard M14 would shoot 1 ½ inch groups with M118 out of a six groove barrel. The same gun would shoot under an inch with Sierra 168 grain Match King bullets! Well under! It has something to do with the thickness of the bullet jacket and the depth of the rifling grooves. Sierra bullets had thinner jackets. That’s when we discovered “Mexican Match” ammunition. We just pulled the bullets from our M118 and installed the 168 gr. SMK. About this time, the military started issuing XM852 Special Match which cured all our problems. Barnett still makes these great barrels and they can be had in four groove as well. The four groove seems to shoot about anything.
In the mid 1980’s I discovered Krieger Barrels. They were advertised in the Shot Gun News as being Match Grade and Quality, stainless steel with short chambers. I never heard of Krieger, but I wanted to try just about anything new and I ordered one for my new M14 match rifle. About the same time I purchased a couple of Smith Enterprise’ receivers to try. This turned out to be a great combination. The McMillan stock helped too! Krieger offered SS or chrome molly in 10, 11, and 12 twist, four groove rifling. This is much the same as they offer today. These barrels would shoot ½ inch! Yea for gas guns!
There was also Obermier, Snyder, Schillen, and others, but they did not produce a finished M14 barrel like Barnett and Krieger.
I want to make one thing clear. There are many excellent barrel makers around the country. They all shoot good, but most require custom machining so I am not including them here.
Recently, Wilson Barrels and Criterion Barrels have been available. Wilson has been around for quite awhile and they have an excellent reputation for match grade AR15 barrels. Most AR manufactures use Wilson Barrels. The junior rifle team I help coach has set some 35 National Team and Individual Records, many of them with Wilson Barrels. Right now they are making standard M14 barrels in chrome lined or plain. They are also making some match grade barrels and will soon have medium weight NM barrels on the market.
Criterion is making a similar selection of barrels for the M14. I have installed a couple of the Criterion medium weight SS match barrels on rifles for LRB Arms and I found they shoot very well. The rifling looked smooth as glass too.
Over the years, I have come to prefer 1:10” twist 4 groove barrels for my match rifles. This combination seems to shoot anything well and will shoot the good old M118 Match ammo too!
I found that GI National Match barrels can be good, but they are hard to find in new condition and usually do not shoot as well as commercial match barrels. The medium weight NM barrels produced in 1982-83 were the best of the GI barrels and I think Saco-Lowell probably was the best producer. The standard weight NM barrels are too thin, hence not stiff enough. I see Krieger is now making a standard weight match barrel. It should be an improvement over the GI NM barrel, but it’s still not heavy enough to stand up to the fat barrels. Krieger’s DMR barrel is pretty good and ½ pound lighter than the heavy barrel. The only thing I don’t care for in the DMR barrel is the 1:12” twist (not that it is much of a handicap).
While I’m on the subject of barrels, how many of you have put your eyeball in the breach end and really looked at the throat. A throat gage can tell you the relative amount of erosion, but many times your eye is a much better indicator of the real condition of the throat. I’ve seen dozens and dozens of GI barrels that have chrome plating flaking off in the barrel throat. They often gage two or three, which is normally OK, but the actual condition says it should be replaced. This is very common in GI chrome lined barrels. Almost all GI barrels being sold are used and many are well used. Always look!
I had a Krieger on one of my rifles that measured 3.5 TE. I thought that was probably good to go until I was looking in the chamber with a chamber inspection mirror. There were craters the size of pot holes in the New Jersey Turnpike in the start of the grooves! I thought “this can’t be good”… That was when I changed the barrel. It had 6850 rounds through it. Always look. Only 3.5 TE….
Bluesteelnwood asked about the differences on how the Army and Navy built rifles. It is interesting so I am repeating the thread here.
It goes back to the days of the M1NM rifle. One of the differences was the Navy/Marine Corps would epoxy the hand guards to the barrel. This worked OK, but one had to destroy the hand guards to remove them or make a barrel change. Army style was to glue and screw the upper hand guard to the lower band with the liner removed and ream the front ferrule so it didn't touch the barrel. The lower hand guard was shortened so it would not touch the receiver and epoxy to the lower band. The only problem with this is the operator would have to use some caution when handling the rifle by the upper hand guard so it wouldn't break loose. The Navy also would often free float the barrel by cutting away part of the ferrule and lower band. Sometimes this works OK and sometimes not. The Army would always bed a rifle with pressure on the ferrule/lower band to stabilize the barrel. This system almost always works well.
There are several differences in the way the Army and Navy build M14 rifles.
They both unitize the gas cylinder and barrel band. The Navy welds and the Army screws them together. Both systems work, but I have seen the welds break during competitions and the accuracy goes down the tubes. I have seen a couple of Army gas cylinder shoot the screw loose, but it is easy to tighten them on the spot. Problem solved. When properly epoxy and staked, the screws almost never shoot loose. One thing the Marines did with many (not all) M14 team rifles was welding lugs on the receiver. This really worked well and they did both rear lug and double lug guns. The Army MTU claims they didn't do lugs, but I know they did on some of their guns. The Marines would free float the barrels when bedding and the Army would pressure bed them. The only problem with lug guns is sometimes the weld would break on the lugs.
This results in a big drop in accuracy! Commercial receivers with lugs installed by the factory rarely if ever fail because the receivers are heat treated after the lugs are welded on. I should also note that free floating didn't always work. Both services would rebuild a rifle till it would shoot within standards however. One thing I liked about Marine M14's is that many of their team rifles were equipped with McMillan stocks. The Army always seemed to stick with wood. There are some other minor differences, but these are some of the main ones I know of. Both services built outstanding NM rifles. I was trained to do it the Army way.
By Ted Brown (Shooters Den)
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