BAR problem

[gunrunner100]

I have 2 magnum BAR's in the shop and they are starting to give me fits! Has anyone heard or experienced the degeneration of accuracy with these things? Normally, the BAR shoots extremely well. I have seen one magnum BAR with a broken bolt carrier, which would explain this, but these 2 are not in that category that I can tell (short of magna-fluxing). Both barrels are going to be cleaned for copper, but this doesn't seem like a copper problem. I have swapped scopes, mounts etc...
Any suggestions would be appreciated.
Chris

 

[Dosing]

Indeed usually the BARs are pretty solid. Problems I saw included inconsistent lock-up, barrel fouling and gas tube fouling. The gas/lock up issues were usually the first thing I took care of with BARs and 7400s. Since you have worked the mounts etc, I am sure you are positive it isn't those. Have you tried various loads? The forestock isn't giving you any pressure point issues is it?

 

[madtrapper143]

Forestocks can be an issue in Magnum BARs. I had a .338 that would not shoot well until it developed a crack in the forend then it settled down and started to shoot. A liitle accraglass linked the crack and it was good. I guess a fore stock replacement may have worked also.

cheers Darryl

 

[gunrunner100]

I have tried handloading for the 300 Win Mag, haven't tried for the 7MM yet. I have replaced the timing latch as the original was causing it to short cycle. I'll give it a good cleaning and then try the forend. I did notice that the 7 was vertically stringing on a warm day. My thought was forend.

 

[billybob]

delete

delete

 

[p-17]

How many rounds through these things, by the way? Magnum rifles burn their barrels faster than most people think, and accuracy goes downhill.

 

[gunrunner100]

The 300 has a low round count, but the 7 had been "handloaded" by the previous owner. I have checked the p/o's loads and found them a little hot for the rifle. Max loads in an autoloader don't make for good times...