Why size only top half of revolver brass?

[ghh3rd]

In a list of loading tips, someone mentioned sizing only the top half of brass used in revolvers. Does this practice help promote accuracy somehow, or case life, or both?

Randy

[Shiloh]

I've heard both reasons. I've never tried it. I have .38 brass that is almost as old as me. When it splits, it gets scrapped.

Shiloh

[shooting on a shoestring]

Yes especially if your chambers are large. For instance I have a .45 Colt Blackhawk that has very large chambers. I size the brass only where the boolit seats, leaving the rest of the case large to fill up the chamber and center my boolit. If I full length sized, then my boolit would be resting on the bottom of the chamber, several thousandths off center of the throat.

Additionally, brass hardens when fired (expanded) sized (swaged down) and that promotes case splits. You have to work the case mouth and boolit seating area, but you don't have to do the rest of the case. Now that all changes if you plan to fire the cases in multiple guns. Then you'd better just full lenght size and not get cute.

[ghh3rd]

And I was just thinking (dangerous) of whether the decapping pin could even be adjusted that far out.

[dominicfortune00]

I've heard both reasons. I've never tried it. I have .38 brass that is almost as old as me. When it splits, it gets scrapped.

Shiloh

You could anneal your brass to overcome the work hardened case splits.

[NSP64]

I use Brass only for one gun. I only size the top third. They fit the chambers better.

Don't know if it matters, but why FL size if you don't have to.

[gon2shoot]

I have a couple guns with large chambers, I size the neck/upper 1/3 to have boolit tension. Is it better than full length resizing? I dont know, do what ya feel comfortable with.

There is no magic answer (no matter who tells you) to what works for your gun. Experience will tell.

[ghh3rd]

So from what I gather, it's more to match the size of your chambers, so your boolit is potentially more centered to the throats - makes sense now. So does eliminating some of the stretching and resizing.

Thanks

[runfiverun]

the base is better fitting.
sometimes the bigger boolit to fill the front also to keep things centered is worth looking at.
for instance in my 30 carbine revolver i use 32-20 brass the rims help keep things straight some the short sized brass helps too, then a 313 diameter boolit helps fill the cylinder up.
amazingly ths little revolver shoots like a lazer.
now take my 41 hunter wait it fits like that too with 412 boolits i bout have to shove the things in the cylinder and 413's won't fit unless i turn necks which isn't necessary.

but a tapered case ain't gonna help in a cylinder, a more stepped shape will.

[243winxb]

Sizing only the top half of brass was in the RCBS news letter many years ago. I tried it. Does not work in autos. In revolvers it works till one day the brass no longer will chamber. Then you will be pulling bullets. I do not size completely to the bottom most part of the web area. Placing a nickle between the carbide die and shell holder/shell plate when setting/adjusting the FL die works for me.

[44man]

Works fine for accuracy but as soon as they get sticky to chamber I just FL once the next time I load them.

[Jack Stanley]

Sizing only the top half of brass was in the RCBS news letter many years ago. I tried it. Does not work in autos. In revolvers it works till one day the brass no longer will chamber. Then you will be pulling bullets. I do not size completely to the bottom most part of the web area. Placing a nickle between the carbide die and shell holder/shell plate when setting/adjusting the FL die works for me.


I've never tried sizing only half a case but I could see the cases acting just this way if I did . It would be my luck that one of the chambers would be just far enough off to mess up the whole game and then where whould I be ?:groner:


Ya know I got this mental image of the cases and ammo that shooting on a shoestring has to deal with . Imagine ammo for a 45 colt that has a case body that reminds you of a 44/40 :-PIt'd be enough to make me bang my head on the loading bench , but hey , if it works for ya ........ Come to think of it I think I had a Blackhawk like that once , the cases took a lot of sizing .

Jack