Dressing a barrel

Got this .25 barrel that I want to dress and clean up. Looking at 11 degree muzzle setting. Is there a better angle for a .25 muzzle? Looking for input on machining the clean up angles on the tranfer port and breech end.
Tim

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If the outside and generally machining & bore follow suit ? ... don't waist you time.

Said ... careful dressing up with a dremel using small stones or burrs is a good start.
From there general barrel prep practices that are well covered in like threads.
Crown has no issue being at 90* cut being it is touched up via the brass screw & lapping compound or using a Cratex point in the dremel tool.
 
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Here's s pretty detailed discussion on the topics of crowning, cutting a leade, etc.

 
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As far as the seating chamfer goes, concentric, clean and smooth is the key. The chamfer can be 10° to 15°. But the chamfer should be "on...the barrel centerline" (concentric is the key word). As noted, it should also be smooth, burr free.


As far as the other end !
Angles aren't any sort of big deal...at all. You can ever put a "round" crown at the end of the barrel if you like. A lot of work to do well, but...

Chamfer Accuracy / concentricity...IS a big deal ! If the chamfer (crown !) is not square to the barrel centerline, neither will be the flight of the pellet.
The gas (air in this case) NEEDS to leave the barrel evenly with and around the pellet. If the chamfer is offset, or angled, the air will not leave with the pellet squarely and "evenly", and most likely push the pellet off center.

Mike
 
If the outside and generally machining & bore follow suit ? ... don't waist you time.

Said ... careful dressing up with a dremel using small stones or burrs is a good start.
From there general barrel prep practices that are well covered in like threads.
Crown has no issue being at 90* cut being it is touched up via the brass screw & lapping compound or using a Cratex point in the dremel tool.
“If the outside and generally machining & bore follow suit ? ... don't waist you time”.
Not understanding,
tim
 
“If the outside and generally machining & bore follow suit ? ... don't waist you time”.
Not understanding,
tim
Exterior finish, throat and crown look like crap .. bluntly stated :cautious:
If the bore is of equally poor quality ? .... don't waste you time trying to correct it was the gist of that statement.

Honestly the machining quality is dismal. Viewing shredded o-rings is telling the receiver is equally in need of some clean up / deburring.
 
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Adding to what Motorhead said. On some crap barrels, when setting them up in a lathe, hopefully your machinist will tell you if your barrel isn’t worth messing with. Whether he dials in externally, internally or both like I do, he will know just how close he can get to perfect. I recently have been working on a quite expensive LW barrel. It came off another gun. I noticed when I scoped it, the leade had more tooling marks on half of it. When setting it up to cut my own leade for slugs, I found out why. She’s a little off. It shot pellets just fine but I can’t have this for slugs. But you still have to wonder what you left on the table even with pellets.
 
Here’s an update on the barrel from what I’ve learned in this post I did the flashlight test and also did some mic checks. The first flashlight test is at the Leeds the second one is at 4.5 inches in and the last one is 1.5 inches from the muzzle. Input please. Please this is a Hatsan and not a 3000.00 full house custom. I am not looking to do more than make it an acceptable field gun.
tim

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Very sufficient. I’m still on the fence about very aggressive rifling marks on a pellet and how that translates into pushing pellets out to their max range. Does their drag stabilization overcome the large bites from the rifling? Reasonable pellet distances, I’m sure it doesn’t matter. If your machinist isn’t going to whack you real hard, it’s always fun to see what a run of the mill cheapo barrel is capable of when it’s done right. Not in a mass production assembly line. You might also consider taking him a couple of the pellets you plan to shoot out of the gun.
 
As far as the seating chamfer goes, concentric, clean and smooth is the key. The chamfer can be 10° to 15°. But the chamfer should be "on...the barrel centerline" (concentric is the key word). As noted, it should also be smooth, burr free.


As far as the other end !
Angles aren't any sort of big deal...at all. You can ever put a "round" crown at the end of the barrel if you like. A lot of work to do well, but...

Chamfer Accuracy / concentricity...IS a big deal ! If the chamfer (crown !) is not square to the barrel centerline, neither will be the flight of the pellet.
The gas (air in this case) NEEDS to leave the barrel evenly with and around the pellet. If the chamfer is offset, or angled, the air will not leave with the pellet squarely and "evenly", and most likely push the pellet off center.

Mike
Well said......