Little pop, no bang

Holleyman

Holleyman

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Athabasca, AB
I loaded up 20 rounds of 7.62 X 54R about four nights ago. I used CCI benchrest large rifle primers, 37 grains of IMR 3031 and 174 gr HPBT Matchking. Went to the range today to see how that load shoots and three of the twenty popped the bullet into the throat but the powder didn't burn and one had a quarter second or so delay between the firing pin hitting and the bang. The remainder of the rounds shot well and grouped well.
The consensus at the range is that somehow my powder must have gotten wet. The cases were cleaned with a nylon brush (not tumbled) and necksized only. They were not wet when I was loading them, didn't try to wash my brass. The only thing I can think of is the brass was stored in the basement on a shelf, brough upstairs and reloaded there, maybe condensation?
What do you do you prep to cases to ensure there is no moisture.
 
Holleyman said:
I loaded up 20 rounds of 7.62 X 54R about four nights ago. I used CCI benchrest large rifle primers, 37 grains of IMR 3031 and 174 gr HPBT Matchking. Went to the range today to see how that load shoots and three of the twenty popped the bullet into the throat but the powder didn't burn and one had a quarter second or so delay between the firing pin hitting and the bang. The remainder of the rounds shot well and grouped well.
The consensus at the range is that somehow my powder must have gotten wet. The cases were cleaned with a nylon brush (not tumbled) and necksized only. They were not wet when I was loading them, didn't try to wash my brass. The only thing I can think of is the brass was stored in the basement on a shelf, brough upstairs and reloaded there, maybe condensation?
What do you do you prep to cases to ensure there is no moisture.
Click to expand...

How damp is your basement? :eek:

For condensation to be a real issue, you would nead a serious heat difference between your basement and upstairs loading area.

I don't suppose you checked the powder visually for signs of moisture in these three rounds that did not go off? Did you check the flash holes for obstructions?
 
Well, you're not using an unusually light charge, and 3031 normally ignites fairly easily. Shouldn't need Magnum primers - they SHOULD be just fine. Maybe the powder itself is contaminated or wet? Where was the jug stored?
 
According to my reload books, your 37 grains of IMR 3031 is about 1.5 gr short of minimum starting load.

The shot with the delay sounds like a hang fire, Too much empty space in the case.
 
did you tumble your brass after you deprimed them? I did once and only once. Has some of the media stuck in the primer hole. :redface: Or do you have a bad patch of primers? Try loading afew with new abatch # or Winchester LRP.
 
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Problems...

Many things can go wrong: badly seated primers, contaminated primers, old degraded powder, oil-contaminated casings :confused:, too low a charge (dubious for 3031), etc...
What about the rifle itself?:
How's the headspace? could you check if there's a length difference between the cases that fired correctly and those that pooped? Also check the base-to-shoulder length, too. A headspace problem combined with too short a base-to-shoulder length would allow the round to move forward and the primer not being struck with enough force.
Check the firing pin dimples and compare between those that fired and those that didn't.
Check firing pin protrusion.
Try some military surplus loads in it, just to see if they work, measure the fired casings then compare the dimensions with yours and the official SAAMI standards.
Good luck and if you find something, please tell us.
PP.:)
 
I have head space go/no go gauges and this rifle checks out A-OK. I am wondering if it was a charge problem. I am seriously lacking re-loading data as I have yet to buy any manuals, I am only going off of the Lee data that I have that states a starting load of 32.8 grains and a max load of 37.3 grains of 3031 for a 180 grain bullet. I have 174 Grain so I opted to take the closest load info and run it on the higher side (37 grains) due to the 6 grain bullet difference.
Does anyone have actual recommended load data for a 174 Grain bullet using 3031?
 
I didn't tumble the brass, flash holes were clear at the time of reloading and the primer had enough power to push through the powder, unseat the bullet and lodge it into the throat. Thanks for the help though.
 
is your powder old? does it smell funny?
did you have case lube that may have been in contact with the primers or the powder?
condensation in your powder measure?
 
Holleyman, here is the data you need.

I'm thinking the Lee data is way off.

This is from a fairly new Sierra Reload manual.
I strongly advise you to get one soon.

Sorry I can't make the columns line up correctly.....


.308 175 gr. MatchKing HPBT 7.62mm Russian
Cartridge OAL: 3.000”

.308 180 gr. Spitzer
Cartridge OAL: 3.000"

.308 180 gr. Spitzer BT
Cartridge OAL: 3.000"

.308 180 gr. MatchKing HPBT
Cartridge OAL: 3.000"

.308 180 gr. RN
Cartridge OAL: 2.800"

________ 2300 2400 2500 2600 2700
IMR-3031 39.7 41.3 42.9
IMR-4895 41.4 43.3 45.1
IMR-4064 42.4 44.0 45.6 47.1
IMR-4320 44.9 46.5 48.1 49.6
H380 46.4 49.8 53.2
IMR-4350 49.3 51.5 53.6
IMR-4831 50.0 52.2
H4831 52.8 55.2
Energy/ft.lbs. 2114 2302 2498 2701 2913

Accuracy Load: IMR-4320/48.1 grs.; 2600 fps/2701 ft.lbs.
Hunting Load: IMR-4320/48.1 grs.; 2600 fps/2701 ft.lbs.
Sierra does not recommend MatchKing bullets for hunting applications
 
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Holleyman,
if you're saying there was unburnt powder left in the case when extracted than the powder in that case is no good. Could be wet but it would have to be quite wet not to ignite. Tumble your brass or make certain your cases are dry, load the minimum sarting load at least and try again.
 
Loaded up 25 at 40.0 grains and another 25 at 41 grains. I'm going to see how they shoot on the weekend. Can't believe the Lee data was that bad! Thanks for all the help guys. I also used a heat gun on the brass for about 15 - 20 seconds to make it hot to the touch. This should help eliminate any condensation but I am leaning toward being 4 to 5 grains short on powder being the problem.

Edit - You are right brnolvr, I need to get a couple of reloading manuals, I'll be down to P&D and Wholesale tomorrow... Can't wait.
 
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Cheese, you shoulda said you needed load info when we was at the range, I gots lotso!

Also, try doing a Google search for "7.62X54 loads", you might be surprised.

Further info on original problem: we tapped the powder out of the cases that primered only and it lit reluctantly with a butane lighter. It was either wet or oily, but 90% sure that the problem was water. Source unknown, but unimportant for now.
 
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