10/22 light strikes

[1970gmc4x4]

The Problem Is Fixed but there is good information in here for someone with a similar problem:

out of 10 rounds probably one will have a light strike and not fire. This gun is an old 68' and new to me. I've checked the other cases that fired and they had good strikes, so it isn't an overall light strike, just every once in a while, when it does it i check the round and you can barely see where it has been touched. I thought ok, firing pin is worn. It was flat where other ones are beveled, so i bought a new firing pin and hammer spring too, just to cover that base too. Put it all together and same issue. In the mean time stoned the hammer and added an over-travel screw to the trigger, i mention these but it shouldn't matter it was doing it before and after.

I also checked that the extractor lines up good with the barrel, and that a bullet will slide in and out of the chamber easy (not binding which could hold the bolt out of battery).

All i can think is that is doesn't go into battery every once in awhile, what would cause that?

If it was a constant issue it would be easy to find, but an intermitant problem is hard, Any ideas? Thanks.

[ojisan]

Are the strike marks right on the outside edge of the rim when there is a mis-fire?
In this case, the firing pin may be hitting too high.
Look at the guide rod /charging handle to bolt fit.
Be sure the charging handle does not bind on the guide rod.

[bohoki]

clean the trigger group with some compressed air then spray it down with

[trob]

I would make sure the barrel is on completely (and bolts are tight), then I would clean everything really well.

If that doesn't work, I would get a new hammer spring.

If that doesn't work, I'd start looking at the bolt/charging handle for issues.

[1970gmc4x4]

I already cleaned everything ood and oiled the moving parts in the ttigger group, and put a new hammer spring when i put in the new firing pin, i also used a chisel to help stake the new firing pin a little lower so it won't rise, i'll check this again though, i want to check the bolt spacings but it shouldn't be a spacing issue if it firing fine most of the time.

And as far as where it is hitting the case, it is hard to tell it is so light.

now the bolt to charging handle fit is something to double check, i suppose that could bind

Thanks so far guys, except bohoki, telling me to clean it thats the first thing i tried.

[trob]

I already cleaned everything ood and oiled the moving parts in the ttigger group, and put a new hammer spring when i put in the new firing pin, i also used a chisel to help stake the new firing pin a little lower so it won't rise, i'll check this again though, i want to check the bolt spacings but it shouldn't be a spacing issue if it firing fine most of the time.

And as far as where it is hitting the case, it is hard to tell it is so light.

now the bolt to charging handle fit is something to double check, i suppose that could bind

Thanks so far guys, except bohoki, telling me to clean it thats the first thing i tried.

Edit: nevermind, i re-read the original post

Ok, so you said it has good strikes on 9/10 rounds. Something is holding that round off of the face of the bolt, where it should be. You already said you did it, but the extractor comes to mind (clean/lube spring?). It might catch the round oddly 10% of the time, which keeps the firing pin from hitting the case correctly. Im sure if you post this on RFC, someone over there will be able to give you a better idea. I'm not saying that guys on CG can't help, but I usually have more luck asking over there if Im stumped (i think everyone would agree).

You might need to get the headspace checked on the bolt. But on an old gun, I can't imagine it's been like that it's whole life.

[1970gmc4x4]

awesome info trob, thank you, i'm thinking it is like what you predicted

Another thing i noticed was that the hammer couldn't fall all the way forward like my comparison gun, it would stop at like a 90 degree angle, so i ground to little nub off and now the two trigger groups are equal in power and swing , same problem

so now i figure it has to be the firing pin moving up, even though i staked it lower, it still can move a little bit up, but i don't want to go too far and have to grind it out cause the firing can't move, i might decide to drill and pin the firing pin so it can't move. But the pin has less movement than the good comparison gun, so it probably isn't the issue.

Now here what i think the problem is, side to side movement, when the bolt is forward in battery with a round in the chamber (no trigger, and upside down for analysis), if you pull on the charging handl the bolt move over probably a 16th of an inch, enough for the extractor to move around the case rim and not pull out the case, i never had an ejection issue, but this demonstrates how much movement the bolt has. with a round in the chamber you can move the bolt to the side and have it catch on the face of the bolt so the bullet is not seated, you have to make it happen but it just sit there, i suppose it could happen during firing every once in awhile causing the light strikes,the comparison gun will always seat correctly. The annoying part is on a 10/22 only about half of the bolt is supported then the ejection port is open, now the question is, what can i do to fix this?

Would beveling the bullet seat to make it self align help?

Jb weld on the inside of the frame (sounds kinda half assed, and i don't know how it would hold up, but i should work)?

Thanks.

[ojisan]

Early receivers had a lot of dimension variance in them.
Did you measure the bolt widths on both guns?
Perhaps if somebody was messing with the bolt they thinned it out a little too much.
There is a lot of slop in these guns by design.

JB Weld would not last long.
Perhaps someone can blob some aluminum on with a welder and then you file to fit.
Maybe a steel shim plate held in place with the two trigger group pins.

[1970gmc4x4]

This pic shows the bolt misaligined with the shell, mybe if a gave the bolt a slight bevel by where the arrow is it would hit the shell and align itself, what do you guys think?

[1970gmc4x4]

Early receivers had a lot of dimension variance in them.
Did you measure the bolt widths on both guns?
Perhaps if somebody was messing with the bolt they thinned it out a little too much.
There is a lot of slop in these guns by design.

JB Weld would not last long.
Perhaps someone can blob some aluminum on with a welder and then you file to fit.
Maybe a steel shim plate held in place with the two trigger group pins.

i like the shim plate idea, and yeah the comparison gun is from the 90's and seems to have a way better fit and finish.

[1970gmc4x4]

tried putting the bolt from the newer comparison gun in the screwy one and there is no side ways slide movement. put the old bolt in the new gun and it does the same thing being able to move over and catch. Damn i might have to buy a bolt, i'll try shooting with the other gun's bolt tomorrow i guess.

[trob]

awesome info trob, thank you, i'm thinking it is like what you predicted

Another thing i noticed was that the hammer couldn't fall all the way forward like my comparison gun, it would stop at like a 90 degree angle, so i ground to little nub off and now the two trigger groups are equal in power and swing , same problem

so now i figure it has to be the firing pin moving up, even though i staked it lower, it still can move a little bit up, but i don't want to go too far and have to grind it out cause the firing can't move, i might decide to drill and pin the firing pin so it can't move. But the pin has less movement than the good comparison gun, so it probably isn't the issue.

Now here what i think the problem is, side to side movement, when the bolt is forward in battery with a round in the chamber (no trigger, and upside down for analysis), if you pull on the charging handl the bolt move over probably a 16th of an inch, enough for the extractor to move around the case rim and not pull out the case, i never had an ejection issue, but this demonstrates how much movement the bolt has. with a round in the chamber you can move the bolt to the side and have it catch on the face of the bolt so the bullet is not seated, you have to make it happen but it just sit there, i suppose it could happen during firing every once in awhile causing the light strikes,the comparison gun will always seat correctly. The annoying part is on a 10/22 only about half of the bolt is supported then the ejection port is open, now the question is, what can i do to fix this?

Would beveling the bullet seat to make it self align help?

Jb weld on the inside of the frame (sounds kinda half assed, and i don't know how it would hold up, but i should work)?

Thanks.

I wouldnt grind off anything, nor would I use JB weld to fix it. Ill PM you with the name of the person you should talk to about it.

tried putting the bolt from the newer comparison gun in the screwy one and there is no side ways slide movement. put the old bolt in the new gun and no side movement, but old bolt in old gun there is movement. Damn i might have to buy a bolt, i'll try shooting with the other gun's bolt tomorrow i guess.

From what youre describing, there's nothing wrong with your bolt. It sounds like a problem with the receiver or something else.

[1970gmc4x4]

i double checked the bolt fitment betwen guns and edited my last post, think it could be the bolt

[1970gmc4x4]

so i shot 60 round through it now with out an issue, so i think it is fixed

The problem was the sloppy bolt, so i drove a chisel in the firing pin slot toward the end of the bolt a little to spread the bolt to the same as the comparison gun, raised the aluminum at the trigger group a little to hold the bolt up better, and did a slight bevel on the bol face to make the bolt align itself with the bullet on contact. did these all at once and test fired with 60 rounds and no issues.

Thanks to everyone for their help, much appreciated.

[bobomb]

old 10/22s had a flat face firing pin the newer ones have a more pointed profile for more impact force concentration how do your fired rims look?