IMR 4064 Failure to Ignite

NoSecondBest said:
I’ve loaded for over fifty years and I’ve had something similar happen twice before, and both times it was the same bottle of 3031 powder. I had the primers go off and could barely hear them. Upon pulling the bullets I found the powder clumped together in the case. Problem turned out to be too much empty space in the case and the powder migrated away from the primer. Apparently the distance between the primer and the powder didn’t allow enough heat from the powder to properly ignite the powder. Try using a magnum primer and see if that helps. If not, use a powder that fills the case better.
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Op did try and magnum primer
 
Op did try and magnum primer
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Read what I wrote: did the OP consider there was too much empty space in the case and the powder may have migrated away from the primer? That may not be the problem, but it could be. The OP didn’t say how full the case was.
 
NoSecondBest said:
Read what I wrote: did the OP consider there was too much empty space in the case and the powder may have migrated away from the primer? That may not be the problem, but it could be. The OP didn’t say how full the case was.
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Op stated 7.5x53.5, 147-220g bullets, with 34-38g

Unsure of case fill with this data, neither of my manuals have load data for this cartridge. perhaps someone with quick load could chime in.
 
The case was about 50% full with the lowest charge of 34 grains. I did consider the possibility of it being a little low so I did hold the barrel up and shook after the first few failures to help set the charge back at the primer. Did not make a difference. At the larger charges, the cases were at least 75% full so a non-issue. (by 50% I mean up the entire length of the case not actual 50% capacity because the bottle neck obviously narrows the capacity as you go up)

I'll try to call them this week to see what they say.
 
IMR 4064 is my go to powder for all my center fire rifles, 223, 243, 270, 30-30, 308, 30-06. Works great in all and never had that happen. I have has issues with Federal primers once. hdbiker
 
I once fired about 20 rounds of 7.62 NATO ammo without powder in a Garand.

No bullets stuck in the chamber throat, they barely moved in the case neck.
 
4064 is a relatively easy powder to ignite, but the general rule of thumb with most rifle powders is to load to at least 70% of volume at the low end, and under no conditions load under 60% full because pressure spikes can occur.

So my first thought is your primers are under-pressurizing the case for the purpose of sustaining ignition. For this reason, it is not uncommon for a magnum primer to work better with low case fill, and then for a standard primer to work better (as judged by lowest velocity SD) when the case is full or nearly full.

However, you said you had ignition failure at 75% fill. That can be erratic with a standard primer in a case the size of yours, but failure to ignite at that fill level is odd and start to steer me toward a contamination issue.

Try what Otto suggested, and load a round whose case you can fill with the powder without going overpressure. If that fails, see if you can get a capful of 4064 from a friend who uses it and do a visual comparison. Look for your jug to have an oily gloss on it. That's an early breakdown symptom.

Finally, put enough for several rounds in a sealed (tape works) container with as much desiccant as you can fit in and try it again a month later. (Note that desiccating raises burn rate, so test with maybe a 60% full charge to start).
 
OK so I measured how much 4064 I could cram into an empty case. It held 57.9 grains compressed all the way to the mouth. Doing the math that means my lowest load was at 59% of total compressed capacity. You would never be able to seat a bullet with that load of 57.9 though.

I'll try to go out on Monday with some 308 loads. I also picked up another jug of 4064 which I will try to load up and see if I fare better with that.
 
OK so I just got back from the range. I had loaded some 7.5x53.5 with the original jug of 4064, the new jug of 4064 and more 4895. I also loaded some 308 with the same.

All rounds functioned normally.

So I guess the good news is that the original jug of 4064 is not bad, but I still don't have an explanation for the earlier problems apart from the temperature. Today was nice, almost 60 degrees.
 
The only cold-related thing I can think of that might cause the problem is grease in the rifle stiffening and slowing the firing pin way down. Especially with high primers, that can cause very weak ignition.
 
I did not read whether the firing pin strike was light or else. If you resize the case shoulders too far back, it could cause some head space problems - case moving forward in the chamber when the firing pin strike resulting in no bang. Federal primers are known to ignite more easily than other primers. Somehow there is a mechanical failure in the reload.
 
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