Tuning Scope shots of chamber/port area ...I wanna see em if ya got em.

[Jaxjax]

Reason for post is I want to see the percentage of not so pretty, chamber/port areas of people's barrels. What in the heck process are manufactures doing to get these sorta results ? I suspect something quick & dirty. Maybe it doesn't matter but it sure seems it would.....

 

[nervoustrig]

Looks pretty good to me for an as-machined finish, presumably from a reamer. An abrasive treatment of some kind--Cratex point, wet sanding, etc.--would be the prescription.

As for whether there should be an expectation it was done by the factory, I would say that depends on the price paid.

 

[Motorhead]

CRATEX Points are the BOMB !!! being very useful in barrel prep and finish work , crown & leade work.

 

[Jaxjax]

Those Cratex bits are where I need to be going for pre lands, the only worry is were the transition to lands. Why does that reamer work even have to be done.? Is it because they need to clean off edges of inside of port for no sharp edges.?

 

[Motorhead]

Those Cratex bits are where I need to be going for pre lands, the only worry is were the transition to lands. Why does that reamer work even have to be done.? Is it because they need to clean off edges of inside of port for no sharp edges.?

You need/want a taper leading into the rifling LANDS so that the lead of the pellet/slug is having the land PRESSED INTO the lead and not CUT into the lead.
For a pellet / slug that is chambered into a Non-Taper start of rifling will trend to get looser and looser at it travels towards muzzle because the lead where at contact with each & every land has been removed there becomes very little radial tension within the bore / pellet fit. When the pellet/slug has the Lands PRESSED in there is a tad more radial tension as it moves towards muzzle.

** Then there is the resulting CHAFF of lead pieces shaved away during loading the further those little pieces of lead can foul bore as not all is blown out and the next & next are going over these pieces of lead potentially burnishing them onto the bores land/groove surfaces.