Beeman R7 Tight Breech

[cabellero59]

Hello, I'm new here and I'm learning about the nice, old, Santa Rosa R7 that I purchased.  I think the barrel has a problem because the breech has a very tight choke and once the pullet is perhaps, 6 inches past the breech face, it becomes very loose with perhaps a very light choke at the muzzle, but still much less choke than at the breech.  Is this normal for an R7?  This seems very wrong to me. If I carefully start a pellet at the muzzle, the choke seems perfect and engraves the pellet nicely.  Wondered what the experts thought about this?

The best group I can get with a Leupold 4x at 25 yards with Crossman premier domed pellets is .5 and I think it should do a little better.  JSB's Exacts and Beeman pellets don't shoot at all.

[Zippy]

Sometimes a barrel will get choked when installed into the breech block and have a tight spot. Had a D34 like that that gun was a problem due to this. Polished out the tight spot with JB paste and it did help. If your shooting CPL at 25 yards and getting .5 groups I'd say leave it be, the choke at the end of the barrel is doing it's job still. Push a pellet through the bore if it still meets resistance at the last inch still it's ok in my book due to the way it's shooting. My D34 shot like &^^& with all pellets till I did the bore I'm talking 1.5 at ten yards.

[cabellero59]

JB bore paste it is.  I realize that it won't remove choke but it may polish a bit.  Thanks.