12 Gauge Shell length?

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Twmaster

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I hope this is not too silly of a question...

I recently got my hands on some shotshell reloading components and tools.

Just for grins I was playing with a paper hull. It had the mouth pretty ragged from a loading or two.

The short of it is I loaded the shell with powder, an overpowder card, 3/8 felt wad, 7/8 oz of #8 shot and an overshot card. I cut the ragged end off the hull and roll crimped the case. It looks great.

But it's only 2.1" tall. I'm loading light for an antique 12 ga with a 2-3/4 chamber.

I'm assuming these will shoot safely being short.

12garoll.jpg

Thanks.
 
What type of shtgun is it: damascus, single shot, double?
What powder and how much.
The length of the shell does not tell the whole story. If you put 50 grains of bullseye, an over powder wad, and 7/8oz shot; there would be a problem.
 
15 grains of red-dot. I'm crazy. Not THAT crazy though...

Just concerned about shell length. in the gun.

The gun is a 1919ish German Geha bolt gun. As I said I'm loading light...
 
No problem or issue with the shorter shell from a length standpoint unless it interfers with feeding . Firing the shorter shell in the chamber is a non issue.
 
I was just looking at Alliant's web site and they have reloading data; only a few loads for Red Dot 7/8 and the pressures were anywhere between 6500 psi and 9000psi with 16grs in modern plastic hulls. The primer, shell, wad stack, shot, over shot card, and compression can make huge differences.

With it being a shotgun built after a Mauser, I wouldn't be bothered by bulk 12 ga from Wal-Mart but that is just my first reaction, I don't know anything about these guns.

If the length of the shell was 5 feet and the chamber pressure was 5psi, you would probably be good, if it were 1/2" and 20,000psi...
 
Chamber length represents length of fired case not loaded one. If I were you I would order some low pressure loads from RST Ltd. These are not that expensive and I think you can mix/match your order. I'm NOT saying that gun you have is safe to shoot with any low pressure ammo, but chances of KABOOM are less if your shells are manufactured by professionals. All guns especially real old ones would have to be examined by gunsmith familiar with type before they're shot with live ammo.
 
70mm
sorry, but it's easier to remember and measure that way.
as for actual length, consider, you shoot 'regular' length 2 3/4" in a 'magnum' 3" barrel
AND
they make shorty rounds that are like 1.5"
 
No problem or issue with the shorter shell from a length standpoint unless it interfers with feeding . Firing the shorter shell in the chamber is a non issue.

+2 for this.

When my 2.75 shells wear out and split, I cut them to 2.00 shells, stuff them with a euro-wad and 6 pieces of .311 shot, and in the reserve they go.

They function fine in my mossberg 500.
 
Just remember the shell length is the FIRED shell length - not before firing. Shooting a shell shorter than the listed chamber length is typically OK to do, (as long as you haven't loaded some uber-power zombie slayer to shoot in that old gun :D)
 
Actually, the greater potential problem is in using modern ammo with a star crimp. The fired hull is considerably longer than one with a roll crimp which was near universal when this shotgun was manufactured. Therefore it's chamber will probably be too short for the fired hull from the star crimp which can potentially cause some pressure problems. In the event you want to use off the shelf ammo, insert a fired hull into the chamber. If it goes in smoothly, you have no problem.

I load a lot of black powder shotgun ammo where powder compression is mandatory so in order to use a lighter charge without having to use a lot of wad, I cut the hulls to a shorter length. I even made a jig to facilitate straight and accurate cuts. But I haven't done this with smokeless loads.
 
You have a 1919 Geha with 70mm chamber? Strange.

But as said, shotshell lengths are measured fired with the crimp straightened out.
15 gr Red Dot - 7/8 oz isn't much.
 
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