M305 function test woes

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Stripes

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As you can probably tell my M305 isn't passing a function test so I'm here to brainstorm ideas and theories with you guys.

First it would only intermittently fail in the plastic norc stock. Then I slapped it in my fancy wood USGI stock and now it fails 100% of the time. I've read that stock fitment with the trigger group is the most common cause of this so I assembled the rifle without the stock and attempted to function test it and it passed flawlessly.

Naturally I'm a bit hesitant to start grinding away at this stock. Anything else I should check before going to town on it? My op rod guide is loose (haven't gotten around to fixing that yet) but I don't think that would cause the issue.
 
Going out on a limb here, do you actually have the trigger group properly installed? Take it out and try it again. Sometimes it looks like it fits in, but its not in properly.
 
fiddler said:
Going out on a limb here, do you actually have the trigger group properly installed? Take it out and try it again. Sometimes it looks like it fits in, but its not in properly.
Click to expand...

As far as I can tell it's installed correctly. The notch on the trigger group sits in the groove on the reciever
 
Failure of the function test is sometimes caused by small geometry alignment problems. Before modifying anything try this:
Remove action from the stock. Loosen stock liner screws on the Norc stock. Install action in Norc stock. Tighten stock liner screws. Perform function test. Any improvement? Repeat similar actions for the wooden stock. Any improvement?

https://www.canadiangunnutz.com/for...-your-m305/page2?highlight=Stock+liner+screws
 
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Take lip stick or crayon or something and draw lines around the trigger group. Install into stock. Remove and anyplace the marking rubbed off into the stock, sand that down. Repeat as necessary.
 
Does the right side of the receiver sit flat in the USGI stock? If not, it may need some material trimmed off
 
Going to try all of these suggestions. I'll have to grab some snap ring pliers from work or something else that might work for loosening the stock liner screws

The reciever fits pretty tightly into the stock. Well except for the notch that requires the "popsicle stick mod"
 
Like a couple others already said, On the usgi wood stocks you will probably need to file off a small bit of material. On the right side of the stock directly in front of the selector switch cut out there is a small section of wood that need to be taken down. It's about an inch long and 1/4 inch wide roughly. Should be fairly noticeable.
 
Stripes said:
Going to try all of these suggestions. I'll have to grab some snap ring pliers from work or something else that might work for loosening the stock liner screws

The reciever fits pretty tightly into the stock. Well except for the notch that requires the "popsicle stick mod"
Click to expand...

I've read that using a couple finishing nails held tightly in a vice grip will work as a tool for removing the stock liner screws.

As for where the stock may need fitting, check out these threads:

https://www.canadiangunnutz.com/for...ter-assembly?p=6377356&viewfull=1#post6377356
Shorty1c.jpg




https://www.canadiangunnutz.com/for...5-Wood-stock?p=7249588&viewfull=1#post7249588
DSC01841-1.jpg


As others have mentioned, the red underlined area of the stock may need to be trimmed down a bit to accommodate the longer ledge of the Norinco receiver if it's a commercial stock.
I've read that actual USGI stocks do not need this modification though.
 
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If the wood stock is new, something to try is leave the trigger group clamped into it for a week or two and see if the wood compresses enough to allow the rifle to pass the trigger test.

The only other thing to try is another trigger group, but I've found that with the three Norinco trigger groups I've had, each needed to be "custom" fit to whatever stock they were used in, due to poor quality control tolerances in the Norinco trigger group. That's to say, a friend's Norinco trigger group may or may not work in either of the stocks you have. Maybe you'll have better luck with a USGI trigger group or a Norinco trigger group with USGI internal parts.
 
I have 2 usgi wood stocks, both needed the trim. put receiver and stock together and watch that area as it closes. you can see the interference, or slip a piece of paper in and you will feel which area catches first.
 
If you use a black grease pencil on the edges of the trigger group it will mark the spots where it is hitting the stock so you know where to remove material.
 
djankle said:
Like a couple others already said, On the usgi wood stocks you will probably need to file off a small bit of material. On the right side of the stock directly in front of the selector switch cut out there is a small section of wood that need to be taken down. It's about an inch long and 1/4 inch wide roughly. Should be fairly noticeable.
Click to expand...

sorry man, not correct.
M1A stocks need to be modified..... so anything made specifically for an M1A will probably need the modification you mention. Good examples are boyds and promag M1A stocks, among others.
USGI stocks in original configuration require no modifications to the receiver bearing plane to fit norinco actions correctly.
Like others have suggested, A fitment problem of the trigger group will most likely be addressed at the trigger bearing points under the stock, of which there are 3 bearing locations.
 
Stripes said:
As you can probably tell my M305 isn't passing a function test so I'm here to brainstorm ideas and theories with you guys.

First it would only intermittently fail in the plastic norc stock. Then I slapped it in my fancy wood USGI stock and now it fails 100% of the time. I've read that stock fitment with the trigger group is the most common cause of this so I assembled the rifle without the stock and attempted to function test it and it passed flawlessly.

Naturally I'm a bit hesitant to start grinding away at this stock. Anything else I should check before going to town on it? My op rod guide is loose (haven't gotten around to fixing that yet) but I don't think that would cause the issue.
Click to expand...

I had exactly this problem with an after-market stock (in that case, a Sage EBR) and a Norc M305.

The issue is that the fitment between the action and the stock will pull the seer lower, so it won't engage. Remember, the stock is what connects the trigger group to the receiver, it's not connected to the receiver on its own. You may need to file down the stock.

EDIT: didn't read all the responses, the other posters are spot on about the fitment of the tock being the issue.
 
Holy smokes, so many awesome responses and suggestions! Now that all the holiday madness is over I'm finally going to have some time to work on the rifle. Going to try the loosening the stock liner screws method first and if that fails I'll go to the removing material method.

Also do you guys have any suggestions other than the "popsicle stick mod" to prevent the pin for the spring guide from popping out? Gluing a popsicle stick in there just seems kinda wrong.
 
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