A guy wants me to cut down his BAR barrel to 20 inches. Anyone done this? And if so what about functioning issues? It's a 338 win mag and has a 24 inch barrel now.

There is no reason (regarding functioning) not to cut down the barrel. One looses a little velocity.....possibly 20'/sec per inch.....

I'll agree with Vapodog, I don't see any function problems. I have a (bolt action) 338 Win, Mannlicher stocked, with about a 21" barrel. Make sure he understands there will be a little more muzzle blast. I don't see it as being a serious issue with my rifle, but it will definately be more than he is seeing with the 24" barrel.

he will need ear protection

I totally agree with the fellas above, personally I'd let er rip.

It is one of the rigs I wouldn't mind myself!

MD

I was worried about the gas pressure due to shorter barrel in a semi auto. I've seen some problems with Remington semi's when the barrel is shortened and they short cycled. Usually opening up the gas port helps but I was unsure if this would happen on a Browning Auto Rifle. It's one of the older ones without adjustable ports.