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Discussion Starter #1 (Edited)
Thoughts??? New Kreiger barrel. The following happens about 5% of the time (50 rounds fired creates 5 damaged cases). At first I thought these rings were from the chamber but the position of them are different. Next I thought that this is the result of the cartridges getting stuck or binding on the front edge of the chamber as is comes out of the mag. What is the best way to ease that edge of the barrel?

These are reloads that were FL sized with a Dillon sizing die.
The reloads also were put into a Dillon .308 case gage and all fit nicely.
Barrel was installed and headspaced by LRB.
Mags are CM from 44mag.

"The area that the pencil is pointing to is very sharp. I've looked at my Garands and this edge of the chamber is not sharp. I think that might be the problem. Instead of the case being guided into the chamber, the edge is just cutting it. Maybe some laping compound on this edge.......



http://i439.photobucket.com/albums/qq119/TwinsonFarm/Picture352.jpg
http://i439.photobucket.com/albums/qq119/TwinsonFarm/Picture351.jpg
http://i439.photobucket.com/albums/qq119/TwinsonFarm/Picture350.jpg
http://i439.photobucket.com/albums/qq119/TwinsonFarm/Picture349.jpg
 

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Is this new ammo. I'm assuming it didn't have anything like this on it before it was fired in this new barrel and every round fired in this barrel looked like this. It would seem if there is an imperfection in the chamber large enough to cause this you could see it. You might have to take the bolt out to get at it.
 

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These look like they are being damaged during the loading process not during extraction. Possibly due to misalignment while being pushed or forced into the chamber by the bolt. Couldn't say what's causing this but maybe the alignment of the feeding grooves.
 

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This looks to me like it is Ammo or Ejection related, are these Re Loads? Does it do it with another Brand of Ammo?
Try this, turn Your Spindle Valve to the Horizontal Position, Load a Round and fire it, ease Your Bolt back enough where You can get the fired Round and see what it looks like!GI8
 

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I'd look at the oprod and spring. It looks like the stripping of the round from the magazine is interrupted as the chamber chamfer looks O.K. to me. (Dragging bolt??) It maybe the chamfer and I'll let the experts chime in on the polish job. I'm gonna' follow this one for sure.
 

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I had a bad magazine once that left a similer mark on the brass. The brass was being pushed to the side by the follower and thus hit the barrel wrong. It was a 10 shot mag.
 

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It may be Magazine or feeding Related,but I would Bet that it is not the Chamber, Krieger doesn't make Mistakes like that!ICONWINK
 

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Two me it looks like unsized brass. Never did see if it was reloads or not
 

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looks like the bolts off center line and hitting the lip of the barrel when feeding . top left of the bolt is coming in to high and hitting then moving down in to lock up.putting the angle off for feeding the round.
 

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Who finish reamed the chamber? Krieger? I would get the chamber nice and squeaky clean and check it. Check your brass in a gauge as well if these are handloads or reloads, after sizing it...

Never seen anything like that.
 

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looks like the bolts off center line and hitting the lip of the barrel when feeding . top left of the bolt is coming in to high and hitting then moving down in to lock up.putting the angle off for feeding the round.
Yeah - does look like its happening during feeding for sure. If the bolt is somehow "off center" enough to cause this, then you are going to have to get that thing checked out by someone really competent. That would mean that the bearing surfaces of either the bolt lugs or the receiver are ... "not good".

If these are reloads, try small base sizing, too...
 

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Guys - the OP told us they were reloads in his first post.

OP - do you have a Wilson .308 case gauge? If not, get one.

Are you using the magazine that LRB sent you with the rifle?

My bet is that the problem either is ammo or magazine related. If it does the same thing to factory 7.62 Nato cartridges using LRB's magazine, send it back and get them to fix it.

I don't need a small-base sizing die for the LRB M25 I just got.
 

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My thought is, the brass isn't sized down enough. I had some thing like that till I got a good head space Gage. Now no problems.
 

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I agree with Al Mack on this, I had similar marks left on my brass when I was just full length resizing, started small base resizing. Never had a problem since. Please keep us updated though. It would be interesting to see what the problem is
 

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Discussion Starter #15
I'll try the small base size

I have measured the chamber is it is real tight compared to my 7.62 Garand. I'll try the small base die and go from there. What small base dies do you guys recommend? James
 

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Sharp edges

I see some very sharp edges on that barrel. 90 degree sharp edges are a "no-no" in any machine. Everything gets a slight 45 degree "touch" to remove that sharp edge, everything.

I would not have left those edges that sharp If I machined that chamber.

Also the "marring" of the brass is just after the neck. This contact point is long before the round is even in the chamber, while it's still transitioning between the Magazine and chamber just after hitting the feed ramp area.

I think either the Magazine isn't holding the rounds at the correct feeding angle, or the edge is creating such friction its digging into the case as it "passes by" that edge.

Just my two cents.
 

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I have measured the chamber is it is real tight compared to my 7.62 Garand. I'll try the small base die and go from there. What small base dies do you guys recommend? James
I personally use the RCBS .308/7.62 set of dies, they can be had at midway for about 36$. i also use a L.E. Wilson case gauge. hope this helps
 

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Hey I recognize those kind of marks... my Krieger leaves a smaller version of that on my brass. Happens when loading as the bullet just enters the chamber at an angle and hits the edge. I know your pain... I've lightly filed a rounded edge into the feeding ramp edge and got rid of most of the mark. I filed a little more of a radius after shooting so I have to see if it's resolved next time out.
 

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I see some very sharp edges on that barrel. 90 degree sharp edges are a "no-no" in any machine. Everything gets a slight 45 degree "touch" to remove that sharp edge, everything.

I would not have left those edges that sharp If I machined that chamber.

Also the "marring" of the brass is just after the neck. This contact point is long before the round is even in the chamber, while it's still transitioning between the Magazine and chamber just after hitting the feed ramp area.

I think either the Magazine isn't holding the rounds at the correct feeding angle, or the edge is creating such friction its digging into the case as it "passes by" that edge.

Just my two cents.
This logic makes sense to me. You may go to SB dies and find that it improves the situation, but those edges look very sharp. I have never owned a Kreiger or Douglas match barrel but these five barrels on the table next to me (USGI & ChiComs) all have nice rounded edges where they transition from ramps to chamber and on the circumference of the chamber opening.

It seems to me that going to a SB set of dies when you don't need the cartridges to be smaller to fit in the chamber and be reliably and safely fired would reduce the life of your brass and affect accuracy.

Why spend the extra $$ on a match barrel and then undersize the cartridges? If you are not experiencing failures to feed or failures to go fully into battery I would start by rounding those edges instead of decreasing cartridge dimensions.

I would carefully round the edges with a thin round stone (rod), pulling the rod out of the chamber with each stroke, or maybe a pencil or small diameter dowel with sandpaper over it spun with your fingers would do the same thing. You don't need to remove much, just enough to make a smooth transition.

SS
 

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I would also suggest smoothing the sharp edge on the chamber slightly. ( Only because it makes sense to my un-trained mind...)

Out of curiousity, were the cases sooty before firing or were they clean ? If they were sooty before firing, then probably a feeding issue... (note the lack of soot on the wear marks, easily checked by feeding a few cases ( point muzzle in a known safe direction ), ejecting them, and inspecting them.

Ooops... and does the left most case have a crack forming in it?

As for whether or not your cases a properly sized... do they ( empty cases or fully loaded.. ) fall completely into your chamber? If they hang up at all..( as in need a little push..).then you need to get a case guage and check. I find it odd to think its a sizing issue, simply because most small base dies ( that I have..) help size down the base of the cartridge, at the thick part of the web... and the lower portion of the case appears fine.

I vote that it is the sharp radius on the chamber....remember, the M1A / M14s action is one of the most physically aggressive I know of. I could easily see the force of the action doing just this.
 
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