Barrel set back

[mikeeg02]

Mike,
I didn't mean to leave an impression, more of a fact, old load data for 105 amax ONLY change is the bullet-107 smk.
Thanks Bill

Yea, sorry for the wording. But him just changing to a bullet like that with more bearing surface at a pretty high pressure load is a little foolish IMO, and could be some of the problem.

I would like to see some good pictures of the case that separated if you can get them.

 

[RetiredArmy]

I'll post some tomorrow,if he brings them with him, along with measurements I get. I agree with you, I'm not a fan of shoot this because that's what everybody is shooting or it worked with amax.
Thanks Bill

 

[gunsandgunsmithing]

Just a thought here...If the case were to be tight in the chamber at the shoulder area, plus very excessive hs, it may be forced to stretch at the web, creating the case head separations. Of course then, it can't be a huge amount and still fire.

 

[RetiredArmy]

Just a thought here...If the case were to be tight in the chamber at the shoulder area, plus very excessive hs, it may be forced to stretch at the web, creating the case head separations. Of course then, it can't be a huge amount and still fire.

Mike,
Not sure I'm understanding, Are you talking chamber diameter? The deeper i get into another guys problems, the more I realize I'm no gun smith!!! Lol
Thanks Bill

 

[gunsandgunsmithing]

Mike,
Not sure I'm understanding, Are you talking chamber diameter? The deeper i get into another guys problems, the more I realize I'm no gun smith!!! Lol
Thanks Bill

Bill, that's what I was thinking along the line of but I just don't think it was a good suggestion to even mention. I'm curious what you find and pretty much just typed what was bouncing around in my mind at the moment.
Your problem has me scratching my head.

 

[mikeeg02]

Bill, that's what I was thinking along the line of but I just don't think it was a good suggestion to even mention. I'm curious what you find and pretty much just typed what was bouncing around in my mind at the moment.
Your problem has me scratching my head.

I think once he gets us a few pictures things SHOULD look a little clearer to us. Separation on the second firing is not a common thing. Specially with good brass.

 

[gunsandgunsmithing]

I think once he gets us a few pictures things SHOULD look a little clearer to us. Separation on the second firing is not a common thing. Specially with good brass.

Right! It doesn't all seem to add up.

 

[RetiredArmy]

Bill, that's what I was thinking along the line of but I just don't think it was a good suggestion to even mention. I'm curious what you find and pretty much just typed what was bouncing around in my mind at the moment.
Your problem has me scratching my head.

Mike,
If your scratching your head im doing pretty good because mines about to explode and it's not even my gun.

I think once he gets us a few pictures things SHOULD look a little clearer to us. Separation on the second firing is not a common thing. Specially with good brass.

Mikeeg02,
If all goes like it's supposed to, he'll be here in the morning and we'll see if it is case separation or if it has been torn apart.
Thanks Bill

 

[RetiredArmy]

Here 's the findings!! Number one, bolt did NOT close on no - go gauge. Stripped bolt, checked go and no go. Not sure what happened first time around.
Number 2, new brass measures 1.154 to shoulder with hornady comparator.
Fired brass measures 1.158. His dies Redding full length size sets the shoulder to 1.156 to 1.157 average of 3 pieces sized. Stripped bolt found lands at 1.861 measured to ogive of bullet, his coal set to 1.791 (0.070) jump! Best i can measure at the web new .466 fired .469. Now my head really hurts. Bad brass???
Thanks Bill

 

[gunsandgunsmithing]

Here 's the findings!! Number one, bolt did NOT close on no - go gauge. Stripped bolt, checked go and no go. Not sure what happened first time around.
Number 2, new brass measures 1.154 to shoulder with hornady comparator.
Fired brass measures 1.158. His dies Redding full length size sets the shoulder to 1.156 to 1.567 average of 3 pieces sized. Stripped bolt found lands at 1.861 measured to ogive of bullet, his coal set to 1.791 (0.070) jump! Best i can measure at the web new .466 fired .469. View attachment 1086318 View attachment 1086319 Now my head really hurts. Bad brass???
Thanks Bill

Twice fired Lapua?

 

[RetiredArmy]

Twice fired Lapua?

Yes sir.

 

[gunsandgunsmithing]

Yes sir.

I'd call them and see what they know regarding your lot number(s) and/or send it to them for evaluation.

 

[RetiredArmy]

He told me this morning that 1500 of the 4500 rounds fired are 30 grains of varget with 107 smk.

 

[Ggmac]

What kind of brass was he using before getting case separations ?

 

[RetiredArmy]

I'd call them and see what they know regarding your lot number(s) and/or send it to them for evaluation.

Mike,
After all measurements this morning, that's what I told him. If it were me I would be on the phone Mon morning. Does any one see problems with the numbers other then the long throat (.070) jump?
Thanks Bill

 

[RetiredArmy]

What kind of brass was he using before getting case separations ?

Lapua

 

[gunsandgunsmithing]

Mike,
After all measurements this morning, that's what I told him. If it were me I would be on the phone Mon morning. Does any one see problems with the numbers other then the long throat (.070) jump?
Thanks Bill

Assuming you meant 1.157 instead of 1.567...Nope, not that should cause that on twice fired brass.
Edited, as I typed 1.567 in twice. I think it says what I mean for it to, now. Lol!

 

[Ggmac]

Personally , I wouldn't waste any more brass or bullets down that tube . I suggest a new barrel . Easy enough to do , you already have the gauges .

 

[MikeMcCasland]

Thanks for posting a follow-up; I was legitimately on the edge of my seat about this. That's really strange, nothing except random bad brass makes sense. I agree with Ggmac though; replace the tube... He was probably near/in the throat when that load was developed lol.

 

[RetiredArmy]

Assuming you meant 1.157 instead of 1.567...Nope, not that should cause that on twice fired brass.
Edited, as I typed 1.567 in twice. I think it says what I mean for it to, now. Lol!

Mike,
That's what I ment to type1.157 fat fingers!