Shown below are step by step photos of blocking a .308 Rem 700 magazine to allow the shorter 6BR (6mm BR Norma) to feed out of a Remington 700 action. I've done this conversion many times and it works well. The only magazine that I've done like this that wouldn't feed was for a .20 BR which is shorter than the 6mm BR. The .20 BR needed a longer magazine block. I figure the block from a .221 Fireball and .221 Fireball mag spring would have worked on it. --Mike Bryant, BryantCustom.com

Support Your Site

On the left, is a Remington 700 .223 magazine. On the right, is a Remington 700 .308 magazine
The rear of the .308 magazine has been cut with a Dremel cut off wheel to make ears similar to those used on a .223 magazine to hold the magazine block (the metal spacer at the rear of the mag, visible in top photo).
Here is a photo of the .308 magazine with the ears bent over.
This shows the .308 magazine with the block from the .223 magazine in place.
We cut the rear of a .308 follower to fit in the blocked .308 magazine. The rear of the follower is also beveled to allow the bolt to close without having to push the follower down.
Here is the finished modified .308 follower in place in the blocked magazine. A magazine spring from a .223 magazine is used instead of the .308 spring.