[ripsaw]

As many here know, I am too analytical about everything, not just this rifle platform.....and I have come across something that has me stumped.....The proper way for the op rod guide to be installed.

I have read much and installed many, but most were used and the lip already worn off....some say the raised lip should go rearward, some say forward....I guess this question is truly for the bonafide armorers such as Art , Gus, Jon, etc. etc. etc.....alphabetical order on purpose GI1

I received an op rod guide... N.O.S. in the wrap, and it has a raised lip on one side of the op rod channel hole. The lip is smooth and the stepdown machining is rough, visibly rough.
My question...which way does the op rod guide go, with the lip toward the front , or toward the back of the rifle ?

As stated, I read alot and thought alot...I thought which way would lend more support to the op rod, keeping it aligned and supported throughout its travel cycle....which side at the moment of explosion would receive the most stress or strain,...seems like the front would..... would the return action of the spring be reason enough to face it to the rear to allow for variances in the op rod receiver channel ?....Finally, I gave up and said....why not ask someone that knows?

 

[MemphisMachinists]

Is this lip just on USGI guides. I have only installed two and I was looking them over very closely trying to see if it mattered which way it went. My experience has only been with aftermarket parts and I didn't see a lip. I am not sure I would want to find out I put them on wrong. GI8

 

[jameslawson71]

Is this lip just on USGI guides. I have only installed two and I was looking them over very closely trying to see if it mattered which way it went. My experience has only been with aftermarket parts and I didn't see a lip. I am not sure I would want to find out I put them on wrong. GI8

Ditto. Lip...?

 

[bd111]

I'm not up to speed on that part having a lip, though I know some current-day barrelmakers use their own op rod guide. Does it slide onto the boss the same either direction of the lip?

 

[ripsaw]

Lip

Yes BD, it does slide on the Boss the same either way and measures same I.D. on both sides.
Yes MM, I have only witnessed it on G.I. guides.

The fit on a N.O.S. op rod is very nice and smooth so I know the lip belongs there, unless the rest of the guide was machined improperly and was gouged out, but I don't think so, the lip is polished as you can see in the photo's.

Check and see what you think.....maybe it's a NM ?????
Was there such a thing, seems if there wasn't , there should have been, they got NM everything else.

The entrance channel bevel, or chamfer, is on both sides of the op rod hole too.

 

[bd111]

It's possible I never noticed the lip before (it's not highly pronounced). But in all honesty I can't tell you whether it goes north or south. Ted or Art or Gus will know. NM op rod guide? Who knows. Hell, I was dumbfounded by the "NM" stock ferrule, but we know there was one by numeric code.

 

[MemphisMachinists]

How bizarre! From the picture it looks like the middle of the bore was undercut for clearence. I hope some one can explain this. Mabey it cuts down on the drag?

 

[82nd ABN]

I say it goes in first. In building a few with Krieger op rods I was tought that trip so the oprod starts on the shoulder of the barrel easier. It has noting to do with the oprod. Does this op rod fit tight on the shoulder? I mean to the poin that it needs to be beaten on? If not I say it makes no difference.
Ps never saw a gi op rod with that on it before. Maybe it's just that manufacturer. You can look up the nsn number to find out if it was a unusual one but I don't thi k so.

 

[art luppino]

guide

Ripsaw, I have never that style USGI Guide, maybe something slipped during the milling process. I would install it with the "lip" towards the Rec..

There was never a NM Guide of that particular style, we use to cut a guide in half and weld the bottom part to the full guide to give more purchase on the rod. This did not improve the accuracy, but it did keep the rod in a better position, this was my experience anyway.

This unusual guide should go to a Collector, Bill Rica, I would think would like to have it..

That is a strange item. Art

 

[ripsaw]

guide

Thanks Art, so you are saying it simply slipped past quality control, and the rough machining has been gouged out, behind the normal lip , that is suppose to be the op rod guide actual size, inside diameter ?

Hey, I'm a strange guy....only fitting it came to me.....

 

[art luppino]

Strange Guide

Thanks Art, so you are saying it simply slipped past quality control, and the rough machining has been gouged out, behind the normal lip , that is suppose to be the op rod guide actual size, inside diameter ?

Hey, I'm a strange guy....only fitting it came to me.....

I am saying I don't know how this guide came out as it is. only expressing a possibility. I like it, would use it myself, Art

 

[MemphisMachinists]

Could it be someone cut that out to pack grease in? I have seen similiar ideas in machinery.

 

[ripsaw]

part

I doubt it MM, I opened the original G.I. wrapper myself..unless they did it at the factory.

 

[bd111]

I'd just pin it on and see what happens, maybe hold off on the JB til it passes torture testing.