test firing a rebarrel job - safety measures?

[chop house]

rc20 said: "Shoot it 5 rounds, clean it, see how things look, shoot another 15"

this bbl was described in an auction listing as new unfired takeoff. 204 ruger. it looked unfired, and even looked like it had never been in a receiver. Anyway, i attached the chrono, laid it on the bags, fired a couple rounds from the hip (so to speak) and measured the fired formed brass. i am here typing so nothing went wrong. i headspaced it tight and sure enough the factory brass grew less than 0.001 on my starting loads (w748, speer tnt 39 gr, jump 0.030", new hornady brass, 3600 fps chrono'd).

QD'd the scope back on, and through the next 4 rounds adjusted down 12" and over 4" from my .308 zero. Shot numbers 7,8,9,10,11 went into 0.400", with 4 of them into 0.275. i had an idea what components to use since 748 and tnt's work great in my .223, but to be that lucky is about insane.

What is all this about break-in?

[Ted_Feasel]

rc20 said: "Shoot it 5 rounds, clean it, see how things look, shoot another 15"

this bbl was described in an auction listing as new unfired takeoff. 204 ruger. it looked unfired, and even looked like it had never been in a receiver. Anyway, i attached the chrono, laid it on the bags, fired a couple rounds from the hip (so to speak) and measured the fired formed brass. i am here typing so nothing went wrong. i headspaced it tight and sure enough the factory brass grew less than 0.001 on my starting loads (w748, speer tnt 39 gr, jump 0.030", new hornady brass, 3600 fps chrono'd).

QD'd the scope back on, and through the next 4 rounds adjusted down 12" and over 4" from my .308 zero. Shot numbers 7,8,9,10,11 went into 0.400", with 4 of them into 0.275. i had an idea what components to use since 748 and tnt's work great in my .223, but to be that lucky is about insane.

What is all this about break-in?

Some barrels you are wise to break in as you will reduce how much ammo you go through.. some higher end barrels are lapped finely enough or hand lapped to the point they don't need broken in. Savage barrels tend to be alot rougher than some others.. if you look at the inside of the barrel with a magnify glass of a new savage barrel you will see the surfaced almost looks like a golf ball with just bunches a little bumps and dips and bumps and dips and as you fire that get slapped out but if you leave the carbon and copper in the dips it can pack in there and make it take a lot longer for all of that to polish out

Sent from my SAMSUNG-SM-G935A using Tapatalk

[Ted_Feasel]

Some barrels you are wise to break in as you will reduce how much ammo you go through.. some higher end barrels are lapped finely enough or hand lapped to the point they don't need broken in. Savage barrels tend to be alot rougher than some others.. if you look at the inside of the barrel with a magnify glass of a new savage barrel you will see the surfaced almost looks like a golf ball with just bunches a little bumps and dips and bumps and dips and as you fire that get slapped out but if you leave the carbon and copper in the dips it can pack in there and make it take a lot longer for all of that to polish out

Sent from my SAMSUNG-SM-G935A using Tapatalk

Then in the other hand you have shilen match barrels where they hand lap the last bit out so the surface is smooth as can be and you do have to really worry about lappi g out or breaking in the barrel... it all just depends on how the manufacturer bored the barrel what type of boar they used what type of finishing they did if any some of them do some hand finishing some of them just bore it and let the customer break it in and lap it out

Sent from my SAMSUNG-SM-G935A using Tapatalk

[chop house]

Ted:

yes, i am aware, was mostly kidding about the break in controversy. i am envious of guys i know with even criterion bbls, virtually wiping out the bore in a couple of strokes. meanwhile i pull out my borescope and butch's or some such. i have seen and recorded all sorts of tooling marks, embedded impurities, discontinuities in the bbl steel, chipped out lands, waffle iron patterns, and burnt out throats - Not talking strictly savage here.

one 700 in 243 i picked up used had an eroded throat, rounded lands, and even some pitting spanning two lands. it was intended for rebarrel, until i shot it. groups nicely, but pita to clean... abaolute pita!

[Ted_Feasel]

Ted:

yes, i am aware, was mostly kidding about the break in controversy. i am envious of guys i know with even criterion bbls, virtually wiping out the bore in a couple of strokes. meanwhile i pull out my borescope and butch's or some such. i have seen and recorded all sorts of tooling marks, embedded impurities, discontinuities in the bbl steel, chipped out lands, waffle iron patterns, and burnt out throats - Not talking strictly savage here.

one 700 in 243 i picked up used had an eroded throat, rounded lands, and even some pitting spanning two lands. it was intended for rebarrel, until i shot it. groups nicely, but pita to clean... abaolute pita!

Oh lol... there really are alot of folks that think break in is worthless :)

Sent from my SAMSUNG-SM-G935A using Tapatalk