Problem with Browning BAR and Federal FUSION 7 Rem. Mag.

[Onty]

Friend has Browning BAR, 7 Remington Magnum, earlier model, and tried Federal FUSION 175 grains. Rifle wouldn't cycle. According to him, rifle will eject case and bring a new round into chamber, but wouldn't close the bolt, wouldn't rotate fully. Looks like that bolt doesn't go back far enough to gain momentum and slam forward to finish the cycle.

He also tried Winchester 175 grains, rifle cycles perfectly.

Any idea what's wrong? Has BAR any way of adjusting gas cylinder? Is something wrong with Federal ammo?

Thanks

 

[TSchwab25]

The gun might need cleaning or some bullets just dont work good.

 

[Seedy Character]

The Fusion is normally, very good ammo.
Not a fan of the 175gr, though

I would give gun a good cleaning.
Use a Sharpie to color a bullet
Try to chamber, see if it is rubbing.

The 160gr always worked better, for me.
My preference was 139gr Hornady Ballistic Tip

 

[351 WINCHESTER]

Being an older gun I would suspect the gas system is gunked up. I would take it to a gunsmith for a deep cleaning.

 

[Onty]

Rifle just came from gunsmith, it was cleaned. What puzzles me why it works perfectly with Winchester ammo, but wouldn't with Federal? Could be that Federal is loaded on less pressure!?

As for 175 grain bullet, rifle will be used on wild boars, generally up to 300 lbs, however, occasionally we have even 400 lbs ones.

 

[jmr40]

ALL semi-autos are designed to function with ammo loaded to within a fairly narrow range of pressures. Too much, or too little and you get issues. Very few people use semi's in those cartridges and most ammo manufacturers are making ammo with bolt guns in mind. If the rifle doesn't like Federal, but does like Winchester, then use Winchester.

 

[d2wing]

ALL semi-autos are designed to function with ammo loaded to within a fairly narrow range of pressures. Too much, or too little and you get issues. Very few people use semi's in those cartridges and most ammo manufacturers are making ammo with bolt guns in mind. If the rifle doesn't like Federal, but does like Winchester, then use Winchester.

This

 

[CarJunkieLS1]

If it is fully chambered but the bolt doesn't lock closed, IMO thats not a pressure issue with Federal I believe its a brass size issue with the federal ammo.

 

[Sebastian the Ibis]

What JMR said, find a load that works and stick to it. In 30.06 a BAR is tuned to Garand loads, no idea for 7mm. Those older semi hunting rifles are finicky and need a specific load. But, don’t worry about the pigs, they are not nearly as picky — they will take what you give them without any complaints.

Also, give the locking lugs a deep deep clean to remove any old rust/grease/cosmoline or anything else that might be in the way. I had an old semi I picked up at an estate sale that wouldn’t behave until I gave the lugs an acetone bath to get 20 years of gunk out.