n00b question re. M305 op rod guide

ColKurtz

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Hi guys, the op rod guide on my M305 has a little bit of play, as in it wiggles around a little bit. Is it supposed to do this or be very tight and not move at all?
 
Should be tight. Easy fix. I think theres a step by step fix in the stickies (its more detailed than I can be). Also check the barrel indexing. Many are out. I have one that is out and one isn't. The strange thing is the one that is out of indexing is really really accurate.
Trevor
 
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I've been through the stickies - constantly reference them for information - but I am missing the info on this. The only thing I could find was about getting a longer retaining pin?
 
Okay thanks, I managed to find it after all, and the video you posted is very good.

Okay, another question regarding the gas piston and the cylinder - the guide part of the piston, as in the part that comes out the back of the cylinder and pushes the op rod back - I can "roll" it in my fingers a little bit (a lot?) while it protrudes from the cylinder. My gut tells me this isn't really desirable. It's as if the find folks at polytech or whoever made my rifle made the guide hole in the cylinder way to big. Should it be a snug guide fit?
 
My piston in my norinco has some play too and tend to stay off at an angle a little bit. I don't think it affect operation since I've had no stoppages so far.
 
I've got 300 rounds through my rifle so far without any issues. Just wondering if it's a problem or not. Eventually I would like to replace it with a USGI or match grade cylinder and piston, but I don't think that's going to happen just yet....
 
It's possible that, with enough play, the piston could bind. Maybe not enough to cause a stoppage, but probably enough to affect accuracy. If it were my rifle I'd put a new gas cylinder and piston on my list of future upgrades, but I wouldn't be in a panic about it.
 
Do a tilt test on it by removing the op rod guide and spring then tilt the muzzle upwards and the piston should drop slowly to the bottom. This indicates a tight fit between the piston and cylinder. As well the op rod and bolt should slide back and forth with no binding .
 
Ah yes, the tilt test reveals lots and lots, binding or lack of binding, resistance, friction points, all kinds of things to be indicated by the tilt test. This tilt test also demonstrates all the moving parts in relationship to each other so you can start greasing all the contact points for optimum movement. :)

You guys are saving me a whole whack of typing! :wave:

Cheers and keep helping them nooobs out there!

Barney
 
After I shot it the first time, it was in the safe for 3-4 weeks before I had a chance to strip it down and give it a good "after the first 100 rounds" inspection and cleaning. Oddly enough the piston had seized and I had to gently beat the sucker out of the gas cylinder with a rubber mallet. I suspect it's because maybe I hadn't cleaned the cylinder thoroughly enough after un-boxing it.

That being said, I haven't had any issues with it since. It fully passes all tilt tests. I love this rifle. For some reason no other rifles I have shot put a smile on my face like the M305 does. Most people would refer to it as a "#### eating grin!"

Another issue I have is the front sight is complete junk. The spacing between the "wings" and the center post is asymmetrical. Not only that, the base of the front sight is cut on an angle, so it makes it appear the barrel is out of index when the sight is on the rifle. After pulling the sight off it becomes very obvious the indexing is fine and the sight is garbage.

Suggestions for where to get a replacement from? I've been searching for the last hour and it seems like the only viable option is Brownells.
 
After I shot it the first time, it was in the safe for 3-4 weeks before I had a chance to strip it down and give it a good "after the first 100 rounds" inspection and cleaning. Oddly enough the piston had seized and I had to gently beat the sucker out of the gas cylinder with a rubber mallet. I suspect it's because maybe I hadn't cleaned the cylinder thoroughly enough after un-boxing it.

That being said, I haven't had any issues with it since. It fully passes all tilt tests. I love this rifle. For some reason no other rifles I have shot put a smile on my face like the M305 does. Most people would refer to it as a "#### eating grin!"

Another issue I have is the front sight is complete junk. The spacing between the "wings" and the center post is asymmetrical. Not only that, the base of the front sight is cut on an angle, so it makes it appear the barrel is out of index when the sight is on the rifle. After pulling the sight off it becomes very obvious the indexing is fine and the sight is garbage.

Suggestions for where to get a replacement from? I've been searching for the last hour and it seems like the only viable option is Brownells.

common norc FS malady. take the flash suppressor off. you will probably see that the indexing ridges inside the FS were cut a little off index. if your barrel is indexed properly. the barrel should be verified first.when you say the base of the sight is canted this usually points to the FS. both the barrel and FS could be off. check the barrel index first.If you have a friend with a non norc made muzzle device try that on for fit. that usually shows how far off the norc FS is. If I were hitting the bullseye I wouldn't care if the sight is canted. If you do decide to replace the sight, beware there are different height sight blades. if it works don't fix it.
 
common norc FS malady. take the flash suppressor off. you will probably see that the indexing ridges inside the FS were cut a little off index. if your barrel is indexed properly. the barrel should be verified first.when you say the base of the sight is canted this usually points to the FS. both the barrel and FS could be off. check the barrel index first.If you have a friend with a non norc made muzzle device try that on for fit. that usually shows how far off the norc FS is. If I were hitting the bullseye I wouldn't care if the sight is canted. If you do decide to replace the sight, beware there are different height sight blades. if it works don't fix it.

Probably both the barrel and flash suppressor are slightly off, I can deal with that. What bothers me about the front sight is that the center post is not center. It just doesn't feel right.
 
What's a good upgrade forbthr or rod guide roll pin? I have to fix my guide and I'm pretty sure the pin will disintegrate into 20 pieces when I pound it out. Thx!

Also, what about Tig welding the op rid guide into place? I don't think I'll ever do an upgrade, and as long as it's in the correct spot... Would there be any issue with this?
 
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