Originally Posted by David_Walter
Thinking of this or a 300 BO.

Pros and cons of each?

Mags now are quiet a bit better than they were 8-10 years ago but some may need a little tweeking. Make sure the spring supports the follower front and rear. You can always bend the feed lips up a small amount to to make the bullet tips hit higher on the feed ramps.
Over-gassing has always been a problem. Mid gas barrels work better but an Adj gas block will help barrels that cycle too quick. If you are shooting super sonic the 7.62x39 will be 100-150fps faster than the 300 and the ammo will be cheaper.

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