Here's a fun puzzle to solve. I've recently had a few hangfires, powder blowback (that stings), and the final straw a round that "popped" and the bullet lodged a few inches into the barrel with very little of the powder ignited. The rounds were 7.62x54R, CCI large rifle primers, 150gr sp bullets, and Hodgdon H414 at 44.6 grains. Feel free to share your thoughts and knowledge on why this happened...I'm thinking it's ammo gremlins spitting on my componets when I'm sleepping.

The first thing that comes to mind is that your neck tension is very light, and that the primer discharge is sending your bullet on it's way. That doesn't allow pressure to build normally.

Can you move the seated bullets if you pushed them against a piece of wood or so? FWIW, Dutch.

I suspect your powder is bad. Will still burn if a match was put to it but maybe "clumps" and this condition is evident when hang fires happen. Neck tension has little or no effect to combustion as many benchresters run very little neck tension. Some let the lands seat the bullet. Of course the primers could be bad also. Pull a seated bullet and observe the powder as you pour it out of the case. Look for clumps. Ball powders are notorious for this.

I had the same problem, I switched to winchester primers and the problem disappeared.
Mike

Something is wrong with your powder, your primers, or maybe both! Use LR Magnum primers with ball powders.

could be that your powder is contaminated with oil from case lube - doesn't take alot

What is loading denisty for that combination? If it less than 80%, than I wouldn't find it all that unusual with H414 being a Ball powder. All it takes is light primer or light neck tension, especially if temperatures are lower than normal. I have experienced similar in 30-06 with ball powder.

I did quick check and I would say your load density is around 70%. IMO that is too low for ball powder. Ball powder is very non-linear. By this I mean slight variations in loading parameters can have large effects on performance. IMO you have a dangerous load since you are hangfiring. Under cetain circumstances the bullet may lodge in bore before powder ignites (force of primer) and then pressure will go extremely high.

quote:

Originally posted by MikeN:
I had the same problem, I switched to winchester primers and the problem disappeared.
Mike

ANY primer can get contaminated,and render it useless!As far a "bad" primer i have found in the many years dealing with them that INHO that CCI are the best.They also have a manufactoring record of only one in a million produced is faulty. van

Hey JR, Does it fire Factory Ammo OK?

It may be worth it to check firing pin protrusion. Its very easy to check and adjust on a Mosin Nagant.

IMO it's a problem with the light charge of slow burning ball powder, as has been said. Switching to magnum primers will help somewhat, as will crimping the bullets in with a Lee Factory Crimp Die, but might not completely solve the problem.

I agree with the above posters in that load density and neck tension are the main culprits. Given that the primer did its job I doubt contamination is the problem, and you only mentioned the one specific load. If this problem were a chronic one, I'd be looking for a mechanical reason.

The bullets are crimped with Lee factory crimp die, and powder from the rounds I disassembled flows freely (no clumps). With all of the great feedback I've received, it appears as that I need to either increase powder charge and change to Winchester or Federal primers in LR Magnum (I think Federal are a little stronger, from what I've read), or change to a faster burning powder. Or all of the above. I've never tried new factory rounds. Besides my own reloads on new Norma Brass the only other ammo I've used is surplus...and that ammo just feels a little to hot.

quote:

Originally posted by JR-Dawgg:
...I've never tried new factory rounds. ...

Hey JR, The reason I asked is because there may not be anything at all wrong with your Reloads. Or, the other posters may be correct that switching to a Mag Primer "might" solve the problem.

As inexpensive as the Factory Ammo is for these surplus rifles, it would be the first thing I'd try. If it does Fire, then you know for sure it is a Reloading Problem. If it does not Fire the Factory ammo, then it is something in the "Striker" mechanism:
1. The Bolt needs a thorough disassembly and cleaning.(I'd do this regardless. Spray it down good with something like GunScrubber, or soak it in a "clean glass jar" of gasoline. The jar allows you to see if any crud comes out of the Bolt.)
2. Might be a weak Striker Spring.
3. And the Firing Pin might be a bit short(as said by another poster).
---

The best side benefit from firing the Factory Ammo though is it allows you to measure the Pressure Ring Expansion(PRE) so when you are Developing your reloads you will know for sure you are at a SAFE Pressure Level.

Best of luck to you.

IMO a weak striker spring or short firing pin can give you misfires or double strikes, but not partial burning as described if the load was reasonable in the first place. Pretty much, the primer pops or it doesn't.

Do try the magnum primers.

JRDawg...how are the flash holes in the brass?

I have used a couple pounds of H414 and it ignited well but went to mag primers in the .243Win to see if they would produce a better group which they did in that rifle.But......regular primers did ignite H414 pretty well.I agree with others on bad powder.Especially having a hang-fire.

I have shot lots of milsurp 7.62x54R and it does seem a little on the "warm" side and plenty of residue left in the barrel.Firing pin protrusion is 2mm on Mosin rifles.Easy to adjust with bolt out and in fired position.Usually armorers score mark on the cocking knob and firing pin (flush with cocking knob)is perfect when aligned.But its worth checking.

By the way...what model is the rifle?Some Finn rifles have a .308" bore,I believe M27,M28,and M28/30.

quote:

Originally posted by JR-Dawgg:
Here's a fun puzzle to solve. I've recently had a few hangfires, powder blowback (that stings), and the final straw a round that "popped" and the bullet lodged a few inches into the barrel with very little of the powder ignited. The rounds were 7.62x54R, CCI large rifle primers, 150gr sp bullets, and Hodgdon H414 at 44.6 grains. Feel free to share your thoughts and knowledge on why this happened...I'm thinking it's ammo gremlins spitting on my componets when I'm sleepping.

I would put money on the powder being bad.

IMO your load is too low; according to Quickload 3.2, you should start at 51-52 gr. Max should be at 56 gr. That's only a guess, of course.

Dwagg..... Go here: http://www.realguns.com/loads/762x54r.htm
As you will discover, you are about 15-18 notches too slow on the powder burning rate chart, and are running very much reduced charge weights. A dangerous combination!!!
Were I to load that cartridge, I would start with recommended charges of IMR 3031, or IMR 4895, or something like Varget.
Good luck, and be careful......Grant.

I've decided on pulling the bullets and powder and switching powders. ( I love the Hornady cam lock puller, beats the RCBS hammer method hands down and quieter too)
I never mentioned that the recipe came from the Lee reloading manual. They suggest start charge of 42.8 and maximum of 47.9 - I think I should send an e-mail to them!
Thanks to everyone for their input. I know that if anymore questions arise, this sure as hell is the place to get the right answers!