Neck size question

[snayperskaya]

I have been reloading 54r for my bits of Russian pig iron using a Lee Loader as I don't make many rounds.As you know the Lee Loader only neck sizes the cases and my cases (PPU) are now on their third firing and after prepping and resizing them the neck inside diameter is around .310" and there is obviously insuffient neck tension when seating a .311" bullet.The case overall length has shortened a touch compared to brand new brass but are still within the case oal limits.

Have I got it right that as the case shortens slightly on firing it pulls the brass back and the neck thins out, increasing the internal diameter of the neck to the point the neck will no longer size internally to the correct diameter?.Will full length resizing restore these cases or have they reached the end of the road after three firings?.

[ukrifleman]

snayperskaya,

I checked the neck diameter inside and out of some new PPU 7.62x54R cases for comparison and got the following.

I.D .309/.310

O.D .328/.329

The case neck wall thickness measured across 5 cases at .010/.0115.

As I am sure you are aware, cases will shorten initially as they expand and fire form with the chamber dimensions and will eventually stretch and the wall thickness subsequently diminishes.

Full length sizing will also cause the brass to stretch over time therefore reducing the thickness of the case walls.

If the wall thickness of your brass is still around nominal, I suspect your problem is work hardened brass and I would anneal the cases to remove spring back and restore neck tension.
ukrifleman

[bnz41]

Afternoon

I use a Lyman F/L sizing 2 die set (part No 7452291) every 4th reload on my 54r brass most of mine are Lapua with the odd nny older brass. The PPU ones I have were factory loaded ammo so are only on the 2nd load so neck tension is ok at the moment but they will get F/L sized the next time.

See link https://www.sportsmanguncentre.co.uk/ly ... -2-die-set

[snayperskaya]

Here's the average dimensions of 5 my fired cases....

.0105" neck wall thickness
.310" neck inside diameter
.332" neck outside diameter
2.101" overall lenght of case

And 5 new unfired PPU cases;

.0115" neck wall thickness
.306" neck inside diameter
.329" neck outside diameter
2.101" case overall length

[ukrifleman]

I assume that you removed any rags from the inside and outside of the cases before taking measurements?

I still stand by my previous statement that the cases could need annealing.

ukrifleman

[snayperskaya]

I assume that you removed any rags from the inside and outside of the cases before taking measurements?

I still stand by my previous statement that the cases could need annealing.

ukrifleman

Removed any rags?, what do you mean, why would I have rags inside or outside of the cases?.

I posted the dimensions I got for reference, the oal of the fired cases should be 2.100"......not 2.101" as I put down.

I don't doubt it when you say they may need annealing

[ukrifleman]

Removed any rags?, what do you mean, why would I have rags inside or outside of the cases[/i

I was referring to new brass, which frequently has ragged edges from the forming process.
ukrifleman

[snayperskaya]

Removed any rags?, what do you mean, why would I have rags inside or outside of the cases[/i

I was referring to new brass, which frequently has ragged edges from the forming process.
ukrifleman

Oh I see ...... The case mouths are all smooth, no ragged edges

[Alpha1]

Are the Lee loader dies the only set of dies you have for this caliber. If so I would suggest you invest in a full length sizing die and seater.
Three firings from a case is not good. You should not need to annile after three firings.
I have had several 7.62x54 rifles over the years and never had a problem with case life. In fact I still have a stash of Lapua cases I must have reloaded at least 10 times. I keep them in the hope of acquiring a Nagant sniper at some time in my shooting life time.
Neck sizing in military calibers is not all ways the best way to go yes the Lee loaders are a cheap option but military rifles don't all ways benefit from neck sizing. My preferred option for milsurps unless you are an experienced handloader is to full length resize.

[snayperskaya]

Are the Lee loader dies the only set of dies you have for this caliber. If so I would suggest you invest in a full length sizing die and seater.
Three firings from a case is not good. You should not need to annile after three firings.
I have had several 7.62x54 rifles over the years and never had a problem with case life. In fact I still have a stash of Lapua cases I must have reloaded at least 10 times. I keep them in the hope of acquiring a Nagant sniper at some time in my shooting life time.
Neck sizing in military calibers is not all ways the best way to go yes the Lee loaders are a cheap option but military rifles don't all ways benefit from neck sizing. My preferred option for milsurps unless you are an experienced handloader is to full length resize.

Yes, just have the Lee Loader for this one calibre as it is the only one I reload.I've not had a problem until now and have made some accurate rounds but can't get these cases to neck size.

Would I be correct in thinking that as they go into the Lee Loader they are sizing but when I tap them out the neck is springing back out, thus giving a larger neck diameter?.It is sizing once fired cases perfectly.