Here is a copy of my old post with a couple added notes:

I bought my first B-Mag 3 weeks ago, looked nice, price was right. After owning it for 5 minutes I put a dent in the beautiful thumb hole stock from the bolt going down before it was ready to lock up. After looking at the bolt mechanism I immediately began thinking how to fix this bad design. It took me 3 days in the workshop to come up with something that works very well (listen up Savage it wasn't that hard).

First was to get a new bolt handle then make a polished steel bolt cap, this cap eliminates the round spring clip and holds new bolt handle very tight. Because the bolt handle no longer wiggles, this allows for a larger set screw point to be made to further reduce play (stock screw had .072" point, new one is .095"). These things alone help but will not stop the bolt from going down when pulled back.

The original bolt could have been modified but I wanted to keep all the original parts in case it didn't work.

I then cut a slot in the end of the bolt shaft so a hand crafted locking pin could lock the bolt from turning. Since there is no round spring clip anymore this clears way to drill a hole in bolt handle for a spring loaded push pin to activate the new locking pin.

The bolt now locks in the up position and has very little wiggle. When the bolt is pushed forward the lock is released and allows it to go down. I then fixed the dent in the stock and that will never happen again.

I also added a .005" shim on the bolt handle flat to take up slop.

If the bolt handles had a little more material (tapered part) where the locking pin was drilled a much simpler "U" shaped device could have been used instead of the more complicated modified machine screw I used. I had to have a larger hole on the front and a smaller hole in the back to keep the drill from coming out the side, not much metal there.




It's been working great since this mod and I now enjoy using it without damaging my stock.