reducing hot load - neck expanding needed?


PDA






judaspriest
April 17, 2007, 10:41 AM
Hi,

I got a bit excited at a show and overbought the Olympic 7.62x54R ammo (details here (http://7.62x54r.net/MosinID/MosinAmmo035.htm)). When I got home, I read that it's actually a very hot load, so I'd like to reduce charges by, say, 5% (or maybe 10% even).

I have a Hornady collet bullet puller to remove the bullets, scales to measure the weights and RCBS full sizing dies. My question is whether I should try to expand the case necks before re-seating back the bullet? If so, how would I do that - remove the decapping pin from the RCBS dies and do the full sizing without decapping? BTW, these are berdan (though non-corrosive) primed

I am concerned that if I don't expand the neck a bit, I'll have a hard time seating the bullet back...

Any tips will be greatly appreciated.

Thanks!

If you enjoyed reading about "reducing hot load - neck expanding needed?" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
db_tanker
April 17, 2007, 11:10 AM
judaspriest,

That is how you would do it, but with it being a boat-tail bullet, you shouldn't have too much trouble with reseating the bullet back into the case.


With all things considered, I would suggest a 5% reduction and do 5 rounds.

The pressure will be reduced but not to dangerous levels...for this, it would REALLY help to have a chrony...

MTCW
D

USSR
April 17, 2007, 11:30 AM
judaspriest,

After pulling bullets from a case, you may have to resize the neck, but if you do, you would REDUCE the neck size, not expand it. Since you are in all likelyhood shooting this ammo in a bolt gun, chances are you will still have enough neck tension to hold the bullet.

Don

judaspriest
April 17, 2007, 01:33 PM
Thanks for replies

Yes, this is for bolt-action Mosin M44

Don't have a chronograph, but if I did, how would I tell the dangerously-low velocity threshold?

Don, I am confused, why would I reduce the neck before seating the same bullet? I thought I needed to expand a bit to make seating easier (though with the boattail, maybe indeed I don't have to), then reduce it a bit during seating it back... Would you please clarify?

Thanks again,

JP

Art Eatman
April 17, 2007, 02:04 PM
Think about it for a minute: In the usual process of resizing an empty case, you first over-compress the case neck a bit, and then the expander opens the neck to the proper size. The expander's work is the main deal to have a properly resized case mouth.

If you're going to resize a primed case to the usual "perfection", it must be empty, and the decapping pin removed.

Go to a reloading book. Look up the beginning load and the max load. After emptying the case of powder, use the starting load.

With a bolt gun, odds are that reseating the bullet will be okay, as said in an earlier post. Brass has a certain amount of springiness to it, and may well hold the bullet just fine. Again, as recommended above, just do maybe five rounds and test, insofar as any bullet setback from recoil.

If you get setback but still want to use a lighter load without resizing, single-load when shooting this batch.

Art

Afy
April 17, 2007, 03:32 PM
This is bedran primed ammo... so I dont know how you could safely remover the primer.

How much ammo did you buy?

Go ahead shoot it..as is. A Mosin is not an AI rifle I that would be worried about damaging.

or sell the ammo... and get something else. It certainly wouldnt be worth my while to re-work the load in 100 rounds or more.. but that is me.

snuffy
April 17, 2007, 03:50 PM
Anytime a bullet is seated in a ready to load neck, it expandes the neck slightly. If that bullet is pulled, it leaves the neck slightly oversized, the brass does NOT spring all the way back to the resized diameter. The bullets when seated in those slightly oversized necks, will be loosER than if the necks were resized in a full length die. They might be loose enough to move under recoil, while in the magazine, from recoil of a round being fired in the chamber. Also, they might not feed from the magazine, if they are loose enough to move when hitting the feed ramp.

If you are going to shoot them in a single shot mode, just seat them in the necks and go shooting. The looser necks will result in lower chamber pressures, so a reduction of powder charge will do what you want.

USSR
April 17, 2007, 04:29 PM
...why would I reduce the neck before seating the same bullet? I thought I needed to expand a bit to make seating easier (though with the boattail, maybe indeed I don't have to), then reduce it a bit during seating it back... Would you please clarify?

jp,

As snuffy pointed out, removing a bullet leave the neck in a larger diameter than when the bullet was originally seated. Seating a bullet does not reduce the neck diameter, it increases it.

Don

DWARREN123
April 17, 2007, 08:38 PM
I would either resell it or shoot it, should not hurt anything but may recoil a little more.

judaspriest
April 18, 2007, 10:03 AM
Thanks for all the replies.

I bought 300 rds, didn't want to damage my Mosin if I could avoid it.

If you enjoyed reading about "reducing hot load - neck expanding needed?" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!