[MJMARSHA]

I missed the mark when drilling my ak74 receiver. The right hand aft rivet hole on the front trunnion (I am doing a screw build so the aft "screw hole"} is a little off so I had to egg it out a little bit to get things lined up. Now heres the deal, it is egged out in the upward direction only. The screw head covers it up so you can't see it when everything is all screwed down. I figured everything is ok because these screws need to take a longitudinal shear force and not a vertical shear force. the other two screws on that side (rh) are pretty lined up ok but I am curious what you guys think... If I need to fix this, has anyone had any luck oxy axcetyleyne welding a hole partially shut?

Thoughts please?

 

[ak'sr4me]

You can mig or tig weld the hole on your eceiver back up and redrill in proper location but I wouldn't bother, as long as the screw head covers your hole your good to go. ak'sr4me

 

[hotbarrel]

if you are realy upset by the hole I will weld it for you. and you can redrill it .. just offering.

 

[MJMARSHA]

Thanks for the offer, I really appreciate it. I think my concern is overblown. I suspect it will be ok. Is there really a lot of shear force on these front trunnion screws?

 

[scubadvr]

Last year, WinnR, had a post where by he shared the results of his own test regarding shrear force. It was on the other board. You may want to see if it is available. You may also try sending him an email. WinnR is one of the more techically advanced members and is always willing to give advise when asked.

 

[yosuthnmasa]

In Mechanics class (Statics), we are actually learning about shear stress and bearing stresses. As I read the post, this reminds me of some of the questions we have in class. Wonder if I could figure out how much stress is being applied? We would have to know what kind of force is being exerted when the gun if fired, and exactly what pieces are involved with the force.

 

[Grendeljaeger]

Winn also came up with an idea for a washer for using under the screws on a screw build for the holes with the chamfered opening. This was to force some of the receiver material into the relieved hole just like the swell headed rivets did. This might be something to consider for a better purchase. And although I agree that you may be worrying about something that is not that big a deal it is always better to be safe than sorry.

 

[7.62x39]

Last year, WinnR, had a post where by he shared the results of his own test regarding shrear force. It was on the other board. You may want to see if it is available. You may also try sending him an email. WinnR is one of the more techically advanced members and is always willing to give advise when asked.

Ah Yes, the infamous toothpick experiment.
IIRC, He got three rounds off before the toothpicks broke