I once saw these repro trench mags on sale for about $35 each, so I bought 2 of them.
They installed on a pair of Mauser 98s perfectly fine. A VZ 24 and a FR8.
Last weekend I shot an ORA Sporting Rifle event, which involves shooting a series of 10 shot shoots. The Snap and Mover allow about 8 seconds between exposures for reloading. Since a Mauser is only 5 shot magazine, and controlled feed, it means that after the 5th shot a new round has to be tucked into the magazine. If the rifle has a scope, this can be a bit awkward.
So I decided to try the trench mag with 10 rounds in it.
It worked perfectly. Or almost perfectly.
To make ammo feed properly, I found I needed to block the mag at the back. To do this I took the spring/follower out (the bottom of the mag comes out, too) and I glued (Dollar store contact glue from a tube) a plastic 5.56 stripper clip (1 ½ clips) up the back of the mag. I also glued a piece of stripper clip up the back of the rifle mag well.
The magazine follower needed a lick on the grinder wheel to shorten it a bit so it was a nice loose fit in the magazine.
The only failure was twice the round did not pop all the way up and the bolt passed over it. I saw/felt this happen, so was able to open the bolt, poke the round and then chamber it.
They installed on a pair of Mauser 98s perfectly fine. A VZ 24 and a FR8.

Last weekend I shot an ORA Sporting Rifle event, which involves shooting a series of 10 shot shoots. The Snap and Mover allow about 8 seconds between exposures for reloading. Since a Mauser is only 5 shot magazine, and controlled feed, it means that after the 5th shot a new round has to be tucked into the magazine. If the rifle has a scope, this can be a bit awkward.
So I decided to try the trench mag with 10 rounds in it.
It worked perfectly. Or almost perfectly.
To make ammo feed properly, I found I needed to block the mag at the back. To do this I took the spring/follower out (the bottom of the mag comes out, too) and I glued (Dollar store contact glue from a tube) a plastic 5.56 stripper clip (1 ½ clips) up the back of the mag. I also glued a piece of stripper clip up the back of the rifle mag well.
The magazine follower needed a lick on the grinder wheel to shorten it a bit so it was a nice loose fit in the magazine.
The only failure was twice the round did not pop all the way up and the bolt passed over it. I saw/felt this happen, so was able to open the bolt, poke the round and then chamber it.