For my .308 BM. With a locked 10 round mag I can take it to cali? Correct?
Thanks.

Found them at DSA....

I made mine from an aluminum 20 rounder.  Cut down and bend new floor plate retaining lips.  

I would make it out of a standard 20round fal mag.

I wouldn't cut it down, I would limit it to 10 rounds.

It doesn't matter the length of the mag, provided it could hold only 10 rounds.

If you limit a 20 round mag to 10 rounds, you will get the proper look of the 20 round, no0t the neutered look of a short mag.


Options:

1. Take a piece of small diameter rod and weld it to the floorplate, but in a position that allows you to finagle it back on to the mag.  If it works properly and limits you to the 10 rounds, then weld the floorplate to the bottom of the mag.


2. Modify the follower.   Using some small diameter metal rods, weld 2 to 3 pieces to the follower.
You can weld a piece front & rear.....  or    front, rear, & center.....  or maybe just center.
You can start off long and trim them down until you can finally fit 10 rounds.


3. You can put two rivets through the center of the mag body.  Figure out where you need to put them in order to give you your 10 round limit. Drill through the mag (side to side /left/right).  AK-47 rivets or cut down 1919 rivets might work out nice.    

BM ilsts 5 & 10 round  for 31.95 ea. alot easier than modifying.