im building a 7mm ultra mag and was wondering if the AI mags could be modified to work with it. i havent decided on a stock yet but if i can get the mags to work then an ax chassis would top the list
Gunsmithing 7mm ultra mag
- Thread starter Ragin_cajun
- Start date
Re: 7mm ultra mag
It is somewhat dependent upon which bullet you're shooting. The easy answer is yes and no.
The case shines with 180-200gr bullets and those suckers are LONG. At RUM case length and reasonable freebore lengths with the heavy 7's you're going to quickly run into a mag length issue but this is nothing new to those who shoot big 300's and 338's.
You can get the RUM cases to run in AICS mags but it takes a little work. The changes are not only at the feed lips but also the bead that runs vertically on the magazine. The shoulder on the 300RUM case will get in the way with that bead and cause stack issues. I don't know offhand if the 7 RUM case shoulder is in the same location as the 300 RUM & 338 Edge (338/300 RUM) but if it is you'll need to remove that bead in the mag wall.
There are some threads floating around that show how to do it.
It is somewhat dependent upon which bullet you're shooting. The easy answer is yes and no.
The case shines with 180-200gr bullets and those suckers are LONG. At RUM case length and reasonable freebore lengths with the heavy 7's you're going to quickly run into a mag length issue but this is nothing new to those who shoot big 300's and 338's.
You can get the RUM cases to run in AICS mags but it takes a little work. The changes are not only at the feed lips but also the bead that runs vertically on the magazine. The shoulder on the 300RUM case will get in the way with that bead and cause stack issues. I don't know offhand if the 7 RUM case shoulder is in the same location as the 300 RUM & 338 Edge (338/300 RUM) but if it is you'll need to remove that bead in the mag wall.
There are some threads floating around that show how to do it.
