M14 Forum banner
1 - 20 of 23 Posts

·
Registered
Joined
·
5,431 Posts
Discussion Starter · #1 ·
As I was re-greasing my rifle, I noticed the roller is just moving around in the op rod cut out. I thought it was cracked. Upon removing the bolt from the receiver I saw that the clip has broken in half, therefore it is not holding the roller in place. I have a spare bolt for my other M1a that I am thinking about borrowing the roller and clip from, is there a trick in removing the roller without damaging it or the clip?

Is this breakage a common occurance? What would be the likely root cause of the failure? Between all my M1As I've shot close to 10K rounds, this is the first one on me.
 

·
"Death From Above"
Joined
·
11,641 Posts
Item number 2 on page 65 is the tool you are looking for. I am not sure where to purchase one or if one can be fabricated from a needlenose pliers.
http://www.scribd.com/doc/23347854/...E-Rifle-7-62-MM-M14A1-W-E-Bipod-Rifle-M2-1972

Fulton Armory is listing the roller and clip for $19.95
If you find a source for the bolt roller clip tool please pas the info onto me I would like to buy one for my M14 toolbar
Thanks

PS I found this info on the tool via google search on another forum. Gus Fisher posted it over there if you want o read the ling here it is. He has a recommendation as well in the post. You may want to take a look.
http://www.jouster.com/forums/showthread.php?15264-M14-bolt-roller
 

·
Inquisitor
Joined
·
11,356 Posts
I am not sure where to purchase one or if one can be fabricated from a needlenose pliers.
I just used some tweezers when I had to put a new clip on. My M1A had a broken clip out of the box so I had to figure it out from the get go. They can break from corrosion or just wear and tear. Not a common problem but it does happen. Definitely one of the areas to grease every cleaning. I would not recommend taking the clip off of the other bolt. If you do, you'll need two clips. BRSTBOMB
 

·
"Death From Above"
Joined
·
11,641 Posts
Why do you need two Is that what is called for I have not had the need to replace the clip yet. I would imagine a clip and a roller would be a good idea to add to the spare parts. I have all the other internal parts for the bolt in spare parts bin for $20 from futon might not be a bad idea.
 

·
Registered
Joined
·
5,431 Posts
Discussion Starter · #5 ·
Thank you, guys!

I just got off the FA site and ordered the clip and roller, checked Brownells and they have them listed separately. I will order a couple of clips from them. My only reservation now, Brownells' are listed SAI. Then again I do not know if FA's are GI or not. Have not found any GI or claimed to be one. Do not know if the clip whether GI or commercial makes a difference either in this case. My bolt is a GI SA.
 

·
"Death From Above"
Joined
·
11,641 Posts
If it gets it up and running it makes no difference right? I have used some small parts from futon and never had any problems so your ok. Glad we could help>
 

·
Banned
Joined
·
2,325 Posts
As I was re-greasing my rifle, I noticed the roller is just moving around in the op rod cut out. I thought it was cracked. Upon removing the bolt from the receiver I saw that the clip has broken in half, therefore it is not holding the roller in place. I have a spare bolt for my other M1a that I am thinking about borrowing the roller and clip from, is there a trick in removing the roller without damaging it or the clip?

Is this breakage a common occurance? What would be the likely root cause of the failure? Between all my M1As I've shot close to 10K rounds, this is the first one on me.
The breakage is not common, but does happen at the worst times. The cause can be , like mentioned , lack of grease and rust from sitting up, too powerful of a load, bad initial installation from the factory causing breakage during assembly, bad spot face heel cut in the rear of the receiver where the bolt terminates after firing can cause the roller to take the full force of the recoil on the op rod. A bad helix cut in the op rod will also cause this breakage, or a rough cast protrusion left from machining on the op rod helix area. Art Luppino has identified "bolt roller rail impact" also as a bad thing, where the roller contacts the receiver when in battery. There is a sticky on it here and in Arts forum of discussions here. An out of spec op rod on the front stopping point against the receiver, the dogleg, ( too much meat on rod) can cause the same overload impact on the roller by causing the op rod to bottom out during recoil, before the bolt bottoms out on the rear of the receiver. This is very bad for the roller and will not last long like that......When the op rod and bolt are in battery position, the roller should be 3/8" from the front of the op rod helix front cut . Check the inside of the op rod cut for the rough condition mentioned.
 

·
Registered
Joined
·
1,163 Posts
Bolt roller impact under the rear sight

Most of the excessive wear problems associated with the bolt roller are caused by improper contact with the receiver.

The most common occurrence of contact is the area directly below the rear sight pocket on the right hand side. This area should be relieved by the manufacturer to provide clearance for the bolt roller as it moves violently to the rear. Many receivers are not relieved in this area to the extent necessary, and require modification.

I see this problem most often on SAI receivers, which are often not properly relieved in this area. If fact, I've never seen another receiver other than SAI with this problem. It's not a fatal flaw as it's easily remedied, but it is an issue I encounter from time to time.

I took a picture here of a receiver to show the proper clearance, although I don't know if it's visible enough to show the relief.

If you see an indentation in this area under the rear sight on your receiver, you may not have proper clearance for your bolt roller. Wear in this area is not an indication of improper clearance, but a clear indentation is. It may take thousands of rounds to pop the roller, but it's more likely to happen when it is not properly relieved.

For putting on rollers, I use a pair of curved hemostats. They work great. Picture of mine attached.

Third picture is showing proper clearance for the bolt roller. This picture doesn't tell the whole story however because the bolt bounces side to side when it comes to rest at its most rearward position. The amount of lateral play comes into play as well.

The forth picture is a poly. While it has the proper relief cut to avoid contact with the bolt roller, it does not have the ramp on its outer edge.

The last picture shows proper relief and a correct ramp. The ramp helps maintains op rod alignment.
 

·
Registered
Joined
·
5,431 Posts
Discussion Starter · #9 ·
Ripsaw and Jon,

Thank you both for your input. I will check all the items mentioned. The rifle was built back in the 80s for this Palma team member out of Houston back then, he is guessing the barrel has about 1500 rounds and I put close to another 1500 since Christmas. I think I will replace the main spring since I will have to take the rifle apart if I were to do some relief cuts in the areas you guys mentioned.

Again, Thank You !
 

·
Registered
Joined
·
5,431 Posts
Discussion Starter · #10 ·
Just received the confirmation email from SAI that the receiver left the factory on 12/75, so there is no telling how many rounds has been through the receiver and the current bolt, an SA variety.

Just FYI.
 

·
Registered
Joined
·
5,431 Posts
Discussion Starter · #11 ·
Jon and Rip,,

Here are some pics of the areas you guys metioned. PLease comment on the potential root cause.


 

·
Registered
Joined
·
1,163 Posts
Top Picture

Jon and Rip,,

Here are some pics of the areas you guys metioned. PLease comment on the potential root cause.


That top picture shows a receiver that is not properly machined, at least it appears that way from the angle of the picture. I don't see much of a relief cut there at all. Although I can't tell due to glare, it appears there is a spot which shows quite a bit of impact wear from the bolt roller.

Maybe a picture from a 45 degree angle looking back at the recess from the front of the receiver would help clarify.

The bottom picture has an op rod installed so I can't tell if there is impact there or not. You'll need to remove the op rod and take a picture of the rail adjacent to the bolt lug recess.
 

·
Registered
Joined
·
2,408 Posts
Here’s my version of the roller pliers. I went to the fishing section of a discount store and found some crimping pliers for people who like to make their own metal leaders. These pliers start out very thin so I didn’t have to remove that much material to get what I wanted. The original pliers have three or four different openings in them for crimping different diameter lead sleeves. Non of them are big enough for the M1A bolt so the first thing I did was clamp them up and drill the correct opening for the bolt roller stud. I don’t remember off the top of my head the specific sizes used but you can search this forum for previous threads on how others made their pliers and get those specs. After getting the opening right I just used a file to thin the pliers down to the right thickness. The filing went so easy that I figured this steel was pretty soft. So as a last step I applied some Kasonite to these pliers to get some surface hardness just in case I end up using these more than two or three times.

 

·
Registered
Joined
·
1,163 Posts
Looks like a great tool for the job!

Here’s my version of the roller pliers. I went to the fishing section of a discount store and found some crimping pliers for people who like to make their own metal leaders. These pliers start out very thin so I didn’t have to remove that much material to get what I wanted. The original pliers have three or four different openings in them for crimping different diameter lead sleeves. Non of them are big enough for the M1A bolt so the first thing I did was clamp them up and drill the correct opening for the bolt roller stud. I don’t remember off the top of my head the specific sizes used but you can search this forum for previous threads on how others made their pliers and get those specs. After getting the opening right I just used a file to thin the pliers down to the right thickness. The filing went so easy that I figured this steel was pretty soft. So as a last step I applied some Kasonite to these pliers to get some surface hardness just in case I end up using these more than two or three times.

Looks like a great tool for the job......Well Done!
 

·
Registered
Joined
·
5,431 Posts
Discussion Starter · #15 ·
I am answering from phone, I am out of the house. Can't take picture right now. Is there a dimension spec for relief cut on what's the finished from the top to the relief cut?
 

·
Banned
Joined
·
2,325 Posts
I think that Jon has nailed it again Bamban, and also think you should check tab specs on this particular op rod, and op rod rail specs in the receiver for wear, because in order for the bolt roller to strike at the mentioned location ,the op rod would have to have some type lateral movement, ( mentioned by Jon), or some type of non axial support from the helix area of the op rod. In other words, it has to be jumping around somewhere in it's travel motion, and the strikes in this area shown might have only occurred after the roller spring clip was already broken. This would give it way more movement and allow it to hit there.

Another measurement needed is the height inside the helix cut of the op rod roller recess, to determine how much room the roller has, this would be when the bolt is in battery, note where the roller is located, measure that rectangular area, in the rear portion of the op rod for height.

Note also, if bolt roller rail impact is occurring, that this measured area will be reduced drastically and be tight, the roller will look like chafing on the outside of it, ...it is easy to see, can you post pic of the outside of the roller in question.....clean and free of grease ?
 

·
Registered
Joined
·
5,431 Posts
Discussion Starter · #18 ·
Jon,

Here are some more pictures of the receiver and the op rod.










Is the op rod USGI?
 

·
Banned
Joined
·
2,325 Posts
I still think Jon is right. It is definately hitting where he led you to look. Take another bolt and roller combo, place in the receiver, move to rear position, push in on the roller stud only, of the bolt, so that the bolt goes up against the bolt stop side of receiver, then while holding presssure on it, see if you can rotate the roller, a piece of paper will work too just like the rail impact test. Check it along the range of motion coming forward too, while pushing in on the stud, all along the clip guide cutout.....bolt roller impact up front looks fine and non-existent from the pics you posted. Op rod looks fine too.....although,...I think you should send that Winchester G.I. op rod to me just to be on the safe side....I wouldn't want it hurting anything else..GI2........roller looks ok.
 

·
Registered
Joined
·
5,431 Posts
Discussion Starter · #20 ·
Jon,

You nailed it, the bolt roller was indeed kissing the receiver in the area you pointed out. As per Ripsaw's suggestion I pushed a bolt assembly all the way to the back to see if the roller touches the receiver. To facilitate the maneuver I cut a portion of an old M1 spring and took a dummy round inserted into the chamber and used the bullet to hold the spring in place, while the other end is pushing on the bolt face.

I filed the area, marked in black felt tip pen, where it touches till it cleared. Here are a couple of pictures showing the finished product. Should I file some more for more clearance?

Thank you all for your help !






Rip, is that a Winny op rod? Check is in the mail.....
 
1 - 20 of 23 Posts
Top