Question about some failed reloads (.308 win)

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island

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Hi All:

I made up my first batch of .308 win a while back, and had a chance to take it to the range yesterday. For the most part, they worked great, pretty accurate as well. I did, however, have 3 failures-to-fire out of about 40 rounds fired, and I'm wondering what I might have done wrong.

I was shooting them in my Norinco M305, btw. All the reloads were 150gr with 41gr of IMR 4064, winchester primers.

First, a picture of the brass of a successfully fired round (one of the reloads):

PA170008.JPG


The indent in the primer looks very slightly "light" to me, compared to an image of commercial brass fired in the same rifle:

PA170010.JPG


Now a "broadside" view of the successfully-fired reloaded case. A bit of soot and stretch-marks at the mouth. Look normal?

PA170009.JPG


Now the ones that didn't fire: Again, to my eyes it looks like the primer indent is not sufficient for the primer to ignite.

PA170007.JPG

PA170004.JPG

PA170005.JPG


Any comments on what I'm doing wrong?

Thanks!
 
Hard to tell from pic's but the primers on the fired ones looks pretty flat and the primer dent a little cratered. Your charge of 4064 is well below the max.

Bullets look like Rem. core-lok bulk. When I seat them with the cannure in that proximity it's to touch the rifling in a bolt gun. Cartridge length?

It's not unheard of to miss a couple when charging rounds. :oops:
 
i bet if you hit them again they'll go boom- that's what i've found with those gold coloured winchesters in my 44 mag- maybe the primer cups are thicker or something
 
There appears to be some scuff marks near the head of the brass that miss fired. Are you full length resizing and if so are you using a small base die? What I am getting at is the possibility that the round did not fully chamber and the hammer fell while the bolt was out of battery. If this was the case the full firing pin energy may not of been transmitted to the primer. As an experiment, repeat your loading proceedure, then when you are shooting see if the bolt can be pushed forward between shots.
 
Yes, I'm full-length resizing: regular Hornady dies.

I don't think the bolt can be moved after the round chambered, but I'll definitely check again next time I'm to the range.
 
they look like the bullets are seated out too far. the canalure should be crimped at the end of the case. Boomer makes a good point that the bolt may be slightly out of battery. check your COL. if I recall it should be about 2.8"

Brian
 
Could be primers, either hardness or primer seating deepth. I will agree that the bullets look to be seated out too far. If the bullet stops the rifle from going into battery by even .001"-.002" it could cause a light strike.
Make sure the throat and chamber are clean.
 
I was concerned about the bullet seating, but the LOA was correct, or so I thought. I will definitely give it a try seated down to the cannelure.
 
I would be looking at the primer seating depth. If they are not seated properly, the energy is absorbed by the primer moving forward in the porimer pocket.

As was suggested, I bet they go off if you hit 'em again.
 
[quote='Boo]
joe-nwt said:
I would be looking at the primer seating depth. If they are not seated properly, the energy is absorbed by the primer moving forward in the porimer pocket.
Click to expand...

That would be my guess as well.[/quote]

I would agree as well. I bet they would go off if you tried them again. To me, the primer strike doesn't look strong enough. Have a look at your bolt and firing pin - maybe something needs to be adjusted.

:D
 
I considered the primer's not being seated to ther bottom of the primer pocket, but I would be surprised if that was the case. Firstly, island went to alot of trouble taking pictures of both factory and handloaded fired brass. This is not the action of a person who would be careless about seating a primer. Secondly, anyone who has fired a M-305 will know that the action closes with enough violence that it is unlikely that a protruding primer will remain protruding, in fact a slam fire could occur.

No, for some reason I am convinced the rounds were fired while the bolt was slightly out of battery, either because the cases were not resized enough to fully chamber under the spring pressure of the bolt moving forward, or perhaps because the bullets were seated a bit long. Again, I doubt that excess OAL caused the problem, because island does not strike me as the kind of reloader who would change from SAAMI standards without doing some measuring first.
 
The primer does not have to protrude, it just has to be not seated all the way to the bottom of the pocket. Any factory rounds fail to fire?
 
Boomer: You're right, I measured everything to the nth degree :) As far as I can tell, I've seated the primers right to the bottom of the cup, and the factory primers are all at the same level (of course, the factory primers might be a different type of primer too).

The OAL is definitely right, I compared it on each and every case (nervous first-time reloader) :) BUT, I think I'm comparing apples and oranges, in that the lighter bullet (150 gr in my reloads) should be seated down to the cannelure, like the 168gr bullet in the commercial round is.

This WILL make my OAL a bit less than the commercial rounds, though - think this is a problem?

No, all the factory rounds fired fine, and always have in this rifle. I've had a few stovepipes on ejection, but never a FT fire or feed (before this), so I think we can safely blame my reloading skills :)

The seating was the one thing I wasn't confident of, given the way the cannelure was "above" the case mouth like that.
 
When you seat a primer into the case head you are doing two things.

One, you are physically placing the primer in place and more importantly you are "setting" the primer so that it will fire when struck by the firing pin. During manufacturing the anvil in the primer is not in firm contact with the priming compound. When you seat the primer properly you are actually pushing the anvil down into contact with the case head as well as pushing the face of the primer down into firm contact with the primer compound.

If the anvil is not in full contact with both the case head and the priming compound there is a good chance the first hit from the firing pin is only crushing the primer fully into place and in effect "setting" it. That is why Joe mentioned that they probably would fire on a second hit.
 
'Boo: Very interesting! I appreciate the info, and will check the seating for sure. Doesn't the imprint from the firing pin look too "light", though?

That's why I'm tending towards the bullet seating being the problem, but I'll check those primers as well!
 
island said:
'Boo: Very interesting! I appreciate the info, and will check the seating for sure. Doesn't the imprint from the firing pin look too "light", though?

That's why I'm tending towards the bullet seating being the problem, but I'll check those primers as well!
Click to expand...

It could well look "light" as most of the force of the falling pin was used to push the primer forward if our long-distance theory is correct.

What method of primer seating are you using??
 
After re-reading the post, there is no mention of re-sizing. Are these cases full length resized? The case itself can cause the rifle to not return to battery.
 
Well, I have a question then. Is it common for the hammer to fall on a bolt not all the way into battery on a M305? I know nothing about them.

The cannnelure does not necessarily indicate any kind of seating depth. That's why some bullets , such as some Hornady's, have two grooves. Many people seat bullets to match their rifle, not to get the case mouth in the cannelure. The problem would arise if the bullet was seated so far forward it contacted the rifling before the bolt was closed, I highly doubt this is the case here. Especially since you kept the same OAL.ALL that being said, you may want to consider seating them to the cannelure and crimping for an autoloader anyway.

As to the case not being resized completely, in an autoloader, if the case is to large to chamber fully, it is usually wedged pretty tight in the chamber due to inertia of the bolt. Was this the case? Were they hard to extract?

My money is still riding on the primer seating. Let us know if you find anything out.!
 
Thoughts..........

A few weeks ago I had same problem with my 308 Garand. A little more attention to bullet seating and crimping was MY error.
Try and "google" this site: Adjusting Reloading Dies, by Chuck Hawks.
This is an excellent teaching aid, and now and again, I refer to this site to remind myself of proper reloading practices.
Good luck with your efforts..........personnally I think your bullet seating/crimping is a little off...........
Cheers...........
 
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