One time fired lapua will not rechamber.... 700 remage 6br no turn

[jds holler]

Have you used a sharpie on one of your tight/fired cases to see just where the case is too tight?? This can be enlightening. jd

(clue -- it's not always at the shoulder)

 

[chop house]

Have you used a sharpie on one of your tight/fired cases to see just where the case is too tight?? This can be enlightening. jd

(clue -- it's not always at the shoulder)

yep. did this already but didn't want to tilt any of the responses or short circuit any ideas that might come from you good folks.

the contact is on the case head, at the edge of the primer hole in a circular swipe. it makes sense with what i get with the datum comparator. I also painted the bolt face and have a nice indication, although my crappy cell phone pics are studio quality.

i'll upload the pics in a bit

 

[chop house]

So when you say it wont close on a fired piece, is it just real tuff or wont budge? Please grease those lugs. Its not unheard of to have brass thats tight but able to close hard. Bump it back with your fl die and see how far it has to go to get right

it is tighter for sure than i would like to force. before i cleaned up the galling some it felt like it was going nowhere when or even before the lugs engaged. now, i can get it started and 'could' force it closed but don't want to... wanting to preserve the data point.

when i am sure i have all that case can tell me, i will incrementally resize to see how far i have to go, rememebering the rifle lockup is now not exactly the same as at firing due to the lug cleanup.

thanks

 

[chop house]

Have you used a sharpie on one of your tight/fired cases to see just where the case is too tight?? This can be enlightening. jd

(clue -- it's not always at the shoulder)

first contact is always same orientation on the bolt... looking into bolt face it's at 8 o'clock pretty much lined up with the lower lug (which was not making contact before my lapping exercise).

when i am more forceful it moves entirely around in the circular pattern you see here. sorry i have the bolt 'upside down' in relation to the case in the second photo.

 

[Falfan2017]

We had a guy at our range not be able to chamber 6br cases he had necksized. Started taking some measurements and the body was too fat in the lower half of the brass. This could be the case here especially if you can chamber it by forcing it. Full length sizing would resolve this.

 

[Texas10]

Me thinks it's time for a new bolt. It'd probably cost more to rework that one, and you've already identified several defects.

I'd pull the barrel, get a new bolt and lap the lugs in, then install and headspace the barrel with a go gage or new piece of Lapua brass. Hopefully the action body isn't too tore up to save, but if the lugs don't make consistent contact on the lug abutments, take it to a smith and have them touched up unless the price of both is too near the cost of a new or slightly used action. Then it's time to simply replace.

 

[chop house]

one more photo. there is no gas cutting on the bolt face, and the factory tool marks are still distinct.

 

[hogpatrol]

What's your measurement at the .200 line on a piece of fired brass and a new, unfired piece?

 

[chop house]

What's your measurement at the .200 line on a piece of fired brass and a new, unfired piece?

don't have them in front of me, but i did check that earlier. recall i did a chamber cast prior to assembly (it is a used bbl) to verify neck and freebore mostly and since have painted the fired brass with no indication of contact at the base. i have the numbers in my notes, just have to look them up. everything matched up or at least was not alarming.... stay tuned

 

[dgray]

Oil in chamber before firing

 

[chop house]

Oil in chamber before firing

that is a possibility or at least a contributor. see the middle of my original post....

 

[david kieffer]

Oil in chamber before firing

My money's on this ^^^^ . Oil or cleaning residue . before you pull it apart ,dry it out and test again. good luck . dave

 

[chop house]

Bump it back with your fl die and see how far it has to go to get right

0.002" it will close. if i was doing a batch i'd prolly go 0.003" to have some margin.

 

[chop house]

What's your measurement at the .200 line on a piece of fired brass and a new, unfired piece?

the offending case chambers after a 0.002" bump. i was hesitant to destroy evidence, that's why i didn't jump right to it.

 

[Brians356]

My money's on this ^^^^ . Oil or cleaning residue . before you pull it apart ,dry it out and test again. good luck . dave

I lightly oil my case bodies with Rem Oil before "bulletless" fireforming 22-250 into 250 AI. The chamber was cut a bit longer than standard for AI (no "crush fit" on 250 Savage cases) and oiling promotes a nice sharp shoulder with the case set back firmly against the boltface.
-

 

[butchlambert]

Ist thing is to check your headspace with a real HS gauge. You need to or have your gunsmith to furnish you with a gizzy. That is a piece of the barrel that has the neck and shoulder reamed to it.
This is the HS gauge, the "gizzy", and a new piece of brass.

Next put your HS gauge in the "gizzy" and take a measurement. Yes, I know it ain't straight, but I think you understand the process.

My photo now shows it with a new piece of brass and it is short as you see.

The new brass means nothing, just shows a pic. Next you take your fired piece of brass and remove the primer, but no sizing yet. Take a measurement
This should tell you what you need to know about your HS in the chamber and of your fired brass. .001 bump should be plenty unless you are using real old brass, throw it away. If you still have an issue it will be brass that is too long or too fat at the .200 mark above the extractor groove.
I have never cared for using brass as a HS gauge and the brass is all over the place HS wise. A headspace gauge is a very minor cost.
Now you can take your threaded rod and pin out of your sizing die and screw the die onto the headspace gauge when it is in the press. This will get you a very good staring place.

 

[Jeff A]

<SNIP>

(caveat: I may have forgotten to dry the chamber. saying that up front)
<SNIP>

There may be other factors but an oily chamber is a non starter.

 

[Ggmac]

I would eliminate bolt lug set back first . Remove the barrel , use a mic from receiver face to 3 points on each lug . If that's not possible insert bolt and take measurements at the bolt face with the bolt beginning its camming and at full seat . Sometimes you can see the bolt lug setbacks without any aid . I would do this first just to eliminate worst case scenario.
Next I'd make sure your receiver face is square / true , using the barrel nut or not having the barrel canted due to the front receiver or recoil lug will make rechambing a fired case difficult UNLESS ITS IS INDEXED AS IT WAS FIRED AND REPLACED EXACTLY .
Hope this makes sense

 

[varget204]

Why would one use a fired case,to set headspace,Not very Accurate,spend $35-40,get a Good Go gage,Manson are precision gages,use .001 to.002 shim stock,piece of paper,tape,on back of Go gage for No go gage,That gives you Minimum Headspace,A lot of fired cases are not true,plus barrel chamber being worn.Is there anyway to tell if barrel was headspaced correctly in the 80's

 

[johnfred1965]

I'm with Texas10 and Ggmac, if the bolt is snapping into place and becoming more loose, your extra thou could be coming from there. If they are close to start with, that could push you over the edge length wise. Clean up the lugs and try again.