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Discussion Starter · #1 ·
I am having what I believe is a headspace issue.
Brass would not function after 1 firing.
Have to load 1 round at a time when firing reloaded brass.
Fired brass is stretched to the point of not being reusable.
Also, the bcg just falls out of the upper when in battery with the muzzle pointed up.
My other ARs the bcg will stay locked.
(Upper separated from the lower of course.)
My question is can the headspace be corrected, or is the rifle not usable?
The pic shows the shoulder pushed foward and the base stressed.
New unsized Dasher in the middle for reference.
 

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If your bolt will not lock up properly, I don't think anything can be expected to work correctly. First thing is to try to resolve that problem. Have you tried that bolt in a different carrier to see if it works there?
 

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I'm uncertain what "wildcat" you are loading? What bolt size are you using, e.g., 5.56, 6.8, 6.5? One way a BCG can fall out is if the bolt gas rings are completely worn. Is this a possibility? I had a rifle with 0.025" head-space and it separated the cases.

Unless your shooting fire-forming rounds, I wouldn't be firing the weapon until this issue is resolved.
 

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BTW, does the bolt lock up with no cartridge in the chamber? Wondering if the bullet is into the lands and not allowing the bolt to close. If it does not lock up with no shell in the chamber, then that is a problem
 

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When you did your initial brass fire forming, did you seat the bullet hard into the lands with a moderate powder charge - to keep the primer against the bolt face?
I do not see a false shoulder on the neck of your loaded round - so when you fire formed your brass - it would stretch above the base...not good.
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Suggest splitting one of your fired cases lengthwise, and confirm what appears to be a near head separation. I would Not reload this brass.
 

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Discussion Starter · #7 · (Edited)
New brass will function properly. Once fired brass was very difficult to chamber and would not feed at all from a mag, I had to load 1 round at a time and drop the bcg using the release.
I tried different OALs.
The sized shoulder length now is so close to unfired brass that I can’t measure a difference.
The brass pictured is from a very moderate load, not hot at all.
My question is, can a gun smith get my headspace corrected?
 

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Based on my limited knowledge, mechanical aptitude and reassembly of a couple of uppers .

Yes the head space can be fixed . I can't say about the bolt or the extension but I would venture that one or both are damaged. Most likely if the barrel extension is replaced and head space can be reached you'll be ok .

To my thinking the barrel extension is the weak link in the system by design to allow for a set back failure with bolt capture vs a barrel rupture or bolt and BCG ejection . I may be all wet . But I bet that's where the hang up and failure is.

When in doubt wash it out . 25% of really expensive repairs can be fixed with vigorous cleaning. Of those remaining at least it's clean to work on and you can see what let go .
 

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It's a wildcat so the headspace is determined by the reloader. There is no book number. Seems like my cases measure around 1.2415 using the C Hornady bushing but my book is out in the shop. Don't take that number to the bank.... Check one of your new ones if you have a comparator.

The chamber was cut to fit the Dasher brass shoulder as it comes out of the bag or box and the sizing die should be set to expand the neck to .277 without pushing the shoulder back. After firing, the shoulder should need to be pushed back slightly to set it very close to where the new brass shoulder was and this push back should be in the range of 0.004" or so. I checked a few fired cases and ending up moving the shoulder 3-4 thous back as I recall.

I am still wondering why the bolt does not snap into place as normal on an empty chamber.
 

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As Strawdog said with a wildcat if the headspace is set by the reloader adjusting the die. If the dies are screwed down too far there is too much headspace, if not screwed down far enough there is too little headspace.

If the bolt moves freely in the carrier change the gas rings.

That said, the cases in the photo do not look right. I'll be here in Tennessee until the first of October. Please send the barrel and bolt to me and I'll see if I can figure out what's going on if not I'll just swap barrels.
 

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I believe what you are saying is that the bolt locks up but if you remove the upper from the lower and point the barrel up the weight of the bcg is enough to rotate the bolt and allow it to drop out , is that correct ? Af all if it was not rotating into the extension the firing pin would not strike the primer .


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I also have a 270MSR and I’m getting the same kind of deformity, but I’ve also just generally had cycling problems with it. We have tried everything but headspace at this point and I’m pretty convinced that’s the problem.
 

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Discussion Starter · #18 ·
No and it looks like I have a wildcat that is going to be too expensive to shoot.
I can get only 1 firing out of new brass safely.
Brass shot out of my 270msr is not reusable in my rifle.
 

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Did you see this, several posts ago?
"As Strawdog said with a wildcat if the headspace is set by the reloader adjusting the die. If the dies are screwed down too far there is too much headspace, if not screwed down far enough there is too little headspace.

If the bolt moves freely in the carrier change the gas rings.

That said, the cases in the photo do not look right. I'll be here in Tennessee until the first of October. Please send the barrel and bolt to me and I'll see if I can figure out what's going on if not I'll just swap barrels."

So now we are in the Keys until the first of May, If you want to send it (barrel, bolt, 2 fired cases, and 1 new case if you have one)to me I'll check it out. I may not have all the parts here but if I get it before Christmas I may be able to get my wife to send parts back to me from TN. PM or Email me for address in FL.
 
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