This is a discussion on Unitized Gas System within the The M14 forums, part of the M14 M1A Forum category; In the SA Loaded M1A does not come with a unitized gas cylinder. Aside from the possible "jingling", could this also affect accuracy? My books ...
In the SA Loaded M1A does not come with a unitized gas cylinder. Aside from the possible "jingling", could this also affect accuracy? My books and manuals indicate match conditioning as including a unitized gas cylinder but I don't remember anything about "how" it affects accuracy or match conditioning other than preventing the slight jingle if the front band is loose.
I have also read a thread or two that reference a "free floating barrel" in an M1A. Is this even possible? Doesn't the front band always contact the bottom of the stock? Is this lip on the bottom of the front band removed to make the barrel assembly completely "free floating".
Sorry about the questions, but as I explore the mechanics of the M1A which is deeply interesting, I am running across various things that stump me.
The jiggle will effect accuracy....any rattle or loose parts will. The reason for unitizing is, besides getting rid of the rattle, is to make gas system allignment easier. I'm sure there are some more technical reasons out there....anyone?
A M-14 barrel can be "free floated" while bedding....This is done by blocking the barrel into position during the bedding process. The bottom lip of the front band is ground off as it would be extremely difficult to remove the action from the stock. It would require moving the gas cylinder forward. There are mixed feelings on free floating the barrel as to how much it actually helps. HTH, Hawk
While waiting for others to chime in on the unitized gas system. I have a related question. I think your thread was "When Things go Awry".
Can you elaborate on what happened? Did the Op Rod Guide come loose? If so, how? Isn't there a pin through the guide?
Sorry for all of the questions, but I trying to be a responsible M1A owner and I am really looking at the mechanics of the M1A and attempting to learn as much as possible about it. Like others, I would like to eek anything that I can do (on my part) to maintain and/or make my rifles shoot better.
Thanks for all of your help! You've already done so much!
Tom, For some reason the op rod guide loosened even though the pin is designed to hold it tight.....I tried another pin which didn't tighten it up, so I threw out the guide and replaced it with another and the original pin and it was very tight....whether it was a freak thing or not it is in my book worth checking when things seem to change on "the firing line" :roll:
Tom, for a more technical explanation of the importance of a unitized gas cylinder, I went to Duffs M14 owners guide under match conditioning. He states "the gas cylinder is probably the single most important assembly affecting the accuracy of the rifle. If it is loose or misaligned with the stock, consistent accuracy is unobtainable. As the bullet passes down the bore, vibrations occur and the barrel flexes in a rotating motion. As issued, the gas cylinder and front band are separate components mounted on the barrel. Most gas cylinders will have some motion about the long axis of the barrel. Depending upon the gas cylinder lock and the barrel-thread interface, some longitudinal motion is also possible. The front band, on the other hand, is free to flop back and forth and side-to-side. This situation permits the harmonics of the barrel to change between shots, depending on where the parts arrange themselves after the bullet exits the barrel. ...Modifications must be be performed on the components of the gas cylinder to prevent movement and ensure repeatability of location and pressure shot after shot."
you are close on the money on the gas cylinders.
unitizing by weld or screw method just takes the play out of the cylinderand front band.
also by using shims the gas cyl can be better aligned on the barrel with the gas port thusly a reason to have a port alignment studin your tool box this also prevents fore and aft slop movement. further by peening down one side of the spined gas cylinder retainer guides on the barrel should further squeeze it tight to keep from rattling and keep them from harmonic vibration and movement . . the oprod guide should in addition to being pinned to the barrel by the roll pin be knurled with a hand knurling tool avoid alot of pressure though when using the tool i always practiced on the crap barrel first.
i do this to all the barrels i have military or civilian except for the heavy match which usually is aready locked knurled and pinned depending on who makes it. as an added measure you can epoxy it in place which is a pretty final method of retention use epi seal 10-10 or 20-20 or jb weld this should prevent problems to the oprod and keep it straight on course each shot jeff
Thank you, I think that was a better summation (than having to read all of these books, sometimes confusing to the novice) on how the gas cylinder affects the performance and/or accuracy in an M1A. This one goes into my notebook.
Do you know where a port alignment stud or tool can be found, made or purchased?
the alignment tool can be gotten directly from badger ordnance.
a guy named marty bordsen is the owner a friend and great gun tool and accessory maker.
you can download his parts catalog and order sheet at www.badgerordnance.com . tel 816-455-3704.
marty makes nothing but top drawer tools for the m1 garand m14, m16 rem 700 and scope mounts stuff and the prices are very reasonable.
also you can get his stuff via brownells, shooters choice, and bushmaster or dpms. jeff
Thank you for that information. This is the first time I have been to the Badger Ordnance site. And I must say, that this is one of the most "slickest" looking sites that I have seen. I have already placed it in my "favorites" section. :lol:
As I read and research more on the M14/M1A I am discovering more places that I can acquire tools and equipment to make my life, as an M1A owner, easier, THANKS to advice and heads up that I have received from members such as you, Hawk and the others.
Thank you again for making this "newbies" life much easier. :lol:
Tom, every once and again, check the links forum. there are a lot of good resources there. Badger Ordnance is one of them....posted 2 Sept..... We are always looking for more sites so if ya come across something of interest that isn't there please post it. Thanks, Hawk
I had some time so I cruised over the M14/M1A links and sites. GREAT links/site information! I don't know why I overlooked this area before... I will certainly check this area prior to posting questions. The answer may be right beneath my nose!
If I run across any site that I think will benefit the group, I will be sure to post.
I come here late but in MHO this is one of the best mods you can do
to aid accuracy---of course if you do ALL the mods you get a better
effect overall but if budget doesn't allow this the gas cylinder is a good
deal and a good starting point.I like weld over the screws but there are
a lot of good arguements for the screws but weld is forever :!: ZEITSEF