6Br throat wear

[provarmint]

Probably been asked before so I'll apologize now, how much wear would you expect a 6Br to have in the throat (smoothing out the lead ) in the first 600 rounds ? I have measured 14 thou in 626 rounds in a Pac nor SS S match barrel, 4 groove 1-8, Vit powders exclusively used.
Regards
PV.

 

[bdale]

I measure about 10 to 12 thousants in my 8 twist Brux after about 700 rounds

 

[expiper]

expect .001-.003" per hundred rds,,,,it depends on brand of bbl.--type/amt. of powder--bullet wt./vel.--rate of fire --rounds between cleaning--cleaning methods--etc.........Roger

 

[fm1947]

I'm glad you posted this I'm curious about my wear on my 6br , what and how do
I figure this out first I would need to know what it was new, right?, what do I have to do?

 

[provarmint]

I'm glad you posted this I'm curious about my wear on my 6br , what and how do
I figure this out first I would need to know what it was new, right?, what do I have to do?

http://www.6mmbr.com/catalog/item/1433308/977259.htm

Use this, keep a control bullet (so ogive to base is the same when remeasuring ) and you can measure after your chosen round count.

 

[fdshuster]

I keep a log book for each barrel, and along with round count, the bullet seated to touch length is recorded. Depending on the cartridge, take a length measurement every couple hundred rounds and record that dimension in the book. It's then a simple matter to subtract the length to touch when the barrel was new, from whatever the most current dimension is.

 

[mikecr]

It won't make any difference when you lose an inch of rifling -if the barrel still shoots
I've yet to see where adjustment beyond initial load development setting, is needed for it.

Accuracy will leave when bore constrictions arrive

 

[johara1]

+1 Mike, I don't either....... jim

 

[fm1947]

provarmit, I must have had a brain fart, I have all those tools and log book back to day one on this barrel I have .012 in wear , when I first got it , it would shoot 1/4 moa at 200 yards and under with best at .19 and all 5 shot groups, now I am strugling to get .4 or .5 moa, I guess that is still good but the Sierra's not shooting as they did. Thanks for info

 

[Forum Boss]

expect .001-.003" per hundred rds,,,,it depends on brand of bbl.--type/amt. of powder--bullet wt./vel.--rate of fire --rounds between cleaning--cleaning methods--etc.........Roger

Interesting stats. After 800 Rounds in my PacNor 3 groove, I have .005" of erosion. Barrel is cleaned with wet patches and Wipe-out. Has never been brushed (neither nylon nor bronze brushes ever). Accuracy is same as new. Load mostly Varget with 105 Scenars. Some testing with Norma 203B and H4895.

 

[johara1]

It almost the end of the season and my guns are doing better than the start,maybe a little throat erosion helps but it sure don't hurt and i'm still using the same dozen brushes i had in 1996, so they didn't wear out to many barrels..... jim

 

[provarmint]

provarmit, I must have had a brain fart, I have all those tools and log book back to day one on this barrel I have .012 in wear , when I first got it , it would shoot 1/4 moa at 200 yards and under with best at .19 and all 5 shot groups, now I am strugling to get .4 or .5 moa, I guess that is still good but the Sierra's not shooting as they did. Thanks for info

We all have those days........