Is there an aftermarket +1 mag floorplate for the M70 long mag action? To be used with stronger spring of course.

I haven't seen one, but replacing the factory magazine spring on my Model 70 .375H&H allowed me to increase capacity to four.

George

George what did you replace it with?
What brand?

I believe it was a Wisner magazine spring.

George

My 338 is made from an 30-06 Classic. Its an early one, don't know if thats got anything to do with it but after opening the box to seat 250 Noslers to the base of the neck she holds four 375 H&Hs down. I've used this gun for about 10 yrs. and an always thinking of makeing it a 375.

I don't see how replacing factory mag spring with another will get another round. Who knows, maybe, most replacement springs are stronger for one reason or another. The Wisner stronger spring is designed to be used with a drop floorplate and they told me I'd realize no benefits of any kind by using it in a stock mag. The factory is a real light thin job. The other spring option is the 10% stronger mag spring from Brownells.

A drop in 1+ plate may not exist. All the +1 setups I've seen are designed to work as a unit with a new guard bow, spring and it's +1 plate.

quote:

Originally posted by MTM:
My 338 is made from an 30-06 Classic. Its an early one, don't know if thats got anything to do with it but after opening the box to seat 250 Noslers to the base of the neck she holds four 375 H&Hs down. I've used this gun for about 10 yrs. and an always thinking of makeing it a 375.

That one wouldn't still hold 4 if you convert. Just buy a M70 in 375.

quote:

I don't see how replacing factory mag spring with another will get another round.

The M70 magnum (or at least mine) has a hump in the bottom rear of the spring. (I don't think the non-magnum has the same hump.) When you replace the magnum with a spring without the hump it allows the follower to contact the floorplate. With mine swapped in my 7stw the 4th is very tight but you can get the bolt to close over it. A little file work and it would be perfect. If I use the same rifle and load 375H&H cases in it 4 will fit fine because of the increased taper.

Showbart, all I would change is the barrel. It would work fine. As i said it takes 4 H&Hs in the mag now and ejects them like any factory CRF rifle.

quote:

The M70 magnum (or at least mine) has a hump in the bottom rear of the spring

Exactly.

George

Yeah, it is a short spring too. OK.

The space occupying hump-spring is changed to a flat spring in the M70 300 RUM, and that helps get the box deeper for the 300 RUM cartridges. Windowing the box adds the needed extra width in the cartridge shoulder area.

The old Pre-64 M70 .375 H&H has a slightly wider box and a flat spring with no space wasting hump. It is perfectly designed for 4 down in .375 H&H.

quote:

but replacing the factory magazine spring on my Model 70 .375H&H allowed me to increase capacity to four.

Anybody try this with a .375 Ruger case in a M70 classic ?

My Win (2000 mfg) 70 in .375 wouldn't feed properly, and Winchester warranty repairs just made it worse. If ever a company deserved their fate...

My gunsmith installed a new mag box, he said it was a Winchester part but i don't know what it was originally designed for. Mag now holds 4 easily, could probably force in 5 but the top round would need to be chambered to close the bolt.