Does anyone have experience with Aquila brand 5 MM
Remington Magnum ammo. I have a Remington model
591 rifle that I bought 40 years ago. With Remington
brand ammo it will often shoot 1 1/2" groups at 100
yards. As Remington brand ammo is no longer made,
and Aquila is the only other source of 5 MM ammo, I was
curious if somone could comment on it's accuracy? Any
input is welcome.

Yes, my father has a Remington M592 which had a broken extractor for many years. Once the new ammo came out, we searched around until we found the parts needed to repair the extractor problem (which was no small task either). Once getting the rifle back to spec, we test fired it with the new Aquila ammo. The gun worked for about three shots, then the new extractor started to fail as well. The empty brass coming out of the rifle was really, really dirty. I think it burns so dirty that it makes the empty cases stick in the chamber. We cleaned the rifle and tried again. Same thing happened after about three or four shots. The empty cases stick in the chamber so bad, the extractor end just slips over the rim, and the bolt comes back without the empty case. We did not have any original Remington ammo to try the new extractor since the repair. For the six or eight shots we did get out of it, the Aquila ammo shot fine, just dirty. I would be interested to hear from other shooters as well. Maybe it is the ammo, but it also could be we just don't have the extractor problem completely cured.

Shop around old hardware stores, a long time ago when I lived in San Francisco there was a hardware store that had ammo in stock that nobody bought and they must of had 20 boxes of 5mm ammo. Anyway I think new old stock might be your best bet.

Good luck

Troy