Don't own a Barra 400, but I have shot one. It's a well made gun, fun to shoot. About as accurate as you can expect from a smoothbore BB rifle. Good short range casual plinker.
I converted a select fire Marui Steyr AUG from 6mm Airsoft to .177 BB. It's an electric spring piston gun like the Barra. Machined a new .177 barrel liner, altered the gear ratio and mainspring to be better suited to the heavier steel BB's, and modified the magazine to feed .177. Works well. Accurate enough to plink soda cans on semi auto out to 20-30 yards. Getting around 500 fps with a full auto cyclic rate of 800 rpm. Magazine holds 300 rds, and I get around 4000 shots per battery charge. Uses an 8.4v NIMH battery pack. I'm very much a traditional springer guy, but a little full auto action from time to time is great fun.
View attachment 425433 My next project is to convert this electric 6mm Classic Army FN M249 to .177 BB.
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