What happens to the bore of a new barrel during the first thousand shots?
I believe it takes 2 bricks of 22lr downrange through a new barrel,
before you can confirm the capability of the barrel to produce predictable results.
Problem....as was pointed out, all I'm basing my opinion on is anecdotal evidence.
It's true, no documentation of barrel wear during what we refer to as break-in.
How to accomplish that, eh?
New year, new project....document the effects of the first thousand rounds
through the bore of a brand new 22lr barrel, using a borescope.
Purchased a 26 inch rigid Teslong USB 5 mm borescope.
Ordered a brand new CZ 455 Varmint barrel in 22lr.
Instead of offering an opinion, I'll offer images of target results and the interior of the barrel.
We can draw our own conclusions based on what can be seen.
Started by building a jig to hold the barrel and borescope
so as to be able to duplicate image capture locations.
The rod of the borescope is marked at 1/4 inch intervals.
Images are captured at referenced intervals, down, left, up and right, inside the bore.
That way a comparison can be made of the same spot at different times in the process.
96 images documented, each time, before and at 100 shot intervals for 1000 rounds.
Here are a few before images...
The leade, reamer cut marks visible
Deposits of some sort left in the barrel from the factory
Rough edges left on the lands
Circumferential patterns left from the hammer forging of the barrel
Link to the entire 96 images taken of the bore as shipped from the factory,
after cleaning with Hoppes 9, patches and a nylon brush.
I believe it takes 2 bricks of 22lr downrange through a new barrel,
before you can confirm the capability of the barrel to produce predictable results.
Problem....as was pointed out, all I'm basing my opinion on is anecdotal evidence.
It's true, no documentation of barrel wear during what we refer to as break-in.
How to accomplish that, eh?
New year, new project....document the effects of the first thousand rounds
through the bore of a brand new 22lr barrel, using a borescope.
Purchased a 26 inch rigid Teslong USB 5 mm borescope.
Ordered a brand new CZ 455 Varmint barrel in 22lr.
Instead of offering an opinion, I'll offer images of target results and the interior of the barrel.
We can draw our own conclusions based on what can be seen.
Started by building a jig to hold the barrel and borescope
so as to be able to duplicate image capture locations.
The rod of the borescope is marked at 1/4 inch intervals.
Images are captured at referenced intervals, down, left, up and right, inside the bore.
That way a comparison can be made of the same spot at different times in the process.
96 images documented, each time, before and at 100 shot intervals for 1000 rounds.
Here are a few before images...
The leade, reamer cut marks visible
Deposits of some sort left in the barrel from the factory
Rough edges left on the lands
Circumferential patterns left from the hammer forging of the barrel
Link to the entire 96 images taken of the bore as shipped from the factory,
after cleaning with Hoppes 9, patches and a nylon brush.
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