Cartridge Advice Please!

[Lurchermiss]

I have just purchased a Mossberg 590 Mariner pump action on Sec.1. This is my first shotgun. I originally saw an advert for this shotgun in a shooting magazine with a southern dealer and registered my interest on a Section 2 version that I was told was available. I then went to the shooting show and saw the same gun that was in stock with a Northern dealer and put an immediate deposit on one, as I was waiting for my certificate. When I received this I rang the Northern dealer and said I was ready to collect, but was told they had made a mistake and it was only available in section 1. I then put in for a variation. I then had a call from the Southern dealer saying the Mariner was now in. I said in section 2, yes he said 5 +1 ????????????????. I did not pursue as I was buying elsewhere. Does anybody know what they are selling?? Now to the cartridges! My FLO said that as I am mainly shooting squirrels to get 2.3/4 26 load. When picking up gun I was sold / bought 250 65m Fibre. When visiting my local shooting ground I was told I should have 70m. On the 65m usually the last cartridge does not cycle and I have to remove and reinsert. This does not happen on the 70m. Is the length of the cartridge measured when it is fired? ie then longer. I am totally confused, and if someone could let me know what is best for my gun and the types of cartridge available and the difference in performance etc it would be appreciated.

[Blackstuff]

Pump-actions can be finicky with cartridges much shorter than the chamber length of the gun, i.e. if you have a gun with a 3" chamber you might struggle with 2.5" cartridges. Using 70mm/2 3/4" cartridges should work in most pumps without issue. And before anyone chimes in, yes SOME pumps will work with shorter cartridges, I used to have a Supernova with a 3.5" chamber and worked fine with 2.5" cartridges.

The case length is the fired length of the case. So if two cartridges are described as 2 3/4" / 70mm, they can still be different lengths in their unfired state

If you now know your gun prefers 2 3/4"/70mm cartridges, just stick with those!

[Lurchermiss]

Thanks Mark. I will use up what I have and stick to 70m.

[Kungfugerbil]

Stick to 2 3/4 - if for no other reason than the choice of cartridges carried by most gun shops will be greater than any their size... I have a Winchester pump and it loves 2 3/4 so I feed it them exclusively.

[ChAoS]

A "must view" video for those new to shotguns:

https://www.youtube.com/watch?v=auc-mVzTPV0

Regards,

Mark.

[Lurchermiss]

Thanks Mark for the link. That is really good! Bu

[ChAoS]

Thanks Mark for the link. That is really good! Bu

You're welcome. (While you're on YouTube, take a look at the "Forgotten Weapons" channel; *very* interesting stuff...)

Regards,

Mark.