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Topic: 6mm CM Barrel Replacement (Read 706 times) previous topic - next topic

Re: 6mm CM Barrel Replacement

Reply #15
This is just my opinion bob.. but as carbon gets built up theirs NO solvents that will get all the carbon out.. and through normal cleaning that burnt in hard carbon builds up a little more each time.. to the point you look in there after what you think was a good cleaning and you see all kinds of fire cracking and think well its about time for a new pipe.. when in reality that fire cracking is layers upon layers of carbon that is cracking.. i have started taking mine back down to bare metal every couple hundred rounds.. havnt been doing it long enough to see if it extends barrel life or not yet.. but one thing it has showed me is that i dont have to keep chasing the tune..
Grant

Re: 6mm CM Barrel Replacement

Reply #16
I agree with jerry.. it will take 15 or 20 rounds for it to come back in.. i didnt have to change my seating depth on the rifles i cleaned like that but they all had a long jump to the lands any way.. i find with a long jump that seating depth is more forgiving than being up there close to the lands..

Just hope it comes back in for ya and shoots good again for a few hundred more rounds..

I do have a question for ya bob.. you have probably told me before but what speed are you running this barrel..
 
 Needing ~20 rounds to come back in makes sense.  It usually takes 5-10 after my normal cleaning.  This is the 6CM that I'm working with on the 110g A-Tips which look to like a lot of jump, so don't expect to see much change....but will be watchful.  I've been running them at either 2930ish or recently at 3025ish.  I've been using RL-23 which I hear may be a bit dirtier.

I have a 600 yard NBRSA match tomorrow and seeing this got my attention.  So I pulled the two guns I plan on using tomorrow (6mm Grendel and 6.5CM) and checked them for carbon.  They look a lot better.   Some lite coloring but little to no firecracking and the land transition look clean.  So not going to do anything with them but will keep an eye out for any further build up.  I did check the other 6CM and it looked fine as well but it only has a couple hundred rounds down it.

This was a good exercise to know what to look for and steps to take. 
Bob
If everything seems under control......you're just not going fast enough

Re: 6mm CM Barrel Replacement

Reply #17
I've been mostly concerned about the carbon ring and no so much on the lighter carbon build up.  So do you recommend getting all of the carbon out at each cleaning or is some build up OK?

Seems that different barrels like different levels of “dirty”. Some barrels after a routine cleaning don’t truly settle in for 20-30 rounds. Others are ready to go after 3 foulers. That may be because of different starting levels of clean, but I believe it has more to do with a happy amount of coppering for that particular barrel. That may vary with the type of rifling and the particular bullet being used.

Re: 6mm CM Barrel Replacement

Reply #18
Bob based on your reports of how that rifle has performed, it doesn’t seem that you should consider a different cleaning protocol. Maybe just a very thorough scrub every once in a while.

Re: 6mm CM Barrel Replacement

Reply #19
Bob based on your reports of how that rifle has performed, it doesn’t seem that you should consider a different cleaning protocol. Maybe just a very thorough scrub every once in a while.
 
 Jerry, that is what I'm thinking as well.  After checking some other rifles, they seemed in good shape.  But at this level of carbon, the rifle was not shooting well.....so I learned something and interested to see if it comes back to shooting well.
Bob
If everything seems under control......you're just not going fast enough

Re: 6mm CM Barrel Replacement

Reply #20

 Needing ~20 rounds to come back in makes sense.  It usually takes 5-10 after my normal cleaning.  This is the 6CM that I'm working with on the 110g A-Tips which look to like a lot of jump, so don't expect to see much change....but will be watchful.  I've been running them at either 2930ish or recently at 3025ish.  I've been using RL-23 which I hear may be a bit dirtier.

I have a 600 yard NBRSA match tomorrow and seeing this got my attention.  So I pulled the two guns I plan on using tomorrow (6mm Grendel and 6.5CM) and checked them for carbon.  They look a lot better.   Some lite coloring but little to no firecracking and the land transition look clean.  So not going to do anything with them but will keep an eye out for any further build up.  I did check the other 6CM and it looked fine as well but it only has a couple hundred rounds down it.

This was a good exercise to know what to look for and steps to take.


The reason i asked about the speed was i thought you were using re23 in it and it does seem to burn dirty at the lower charges.. kick it up there and it will burn alot cleaner..
Grant

Re: 6mm CM Barrel Replacement

Reply #21
Can you imagine trying to understand the changes in this barrel without a bore scope?

Re: 6mm CM Barrel Replacement

Reply #22
impossible.... lol
Grant

Re: 6mm CM Barrel Replacement

Reply #23
Can you imagine trying to understand the changes in this barrel without a bore scope?
 
 I was thinking the same thing.  Being able to 'see' what is going on is invaluable. 
Bob
If everything seems under control......you're just not going fast enough

Re: 6mm CM Barrel Replacement

Reply #24
makes a guy wonder how many barrels get pitched when they really need a good deep cleaning..
Grant

Re: 6mm CM Barrel Replacement

Reply #25
Since I switched from JB to iosso I have found it takes much less elbow grease to get down to base metal...100 strokesis good but 200 is batter.
11X Grandfather
Part time Savagesmith

Re: 6mm CM Barrel Replacement

Reply #26
makes a guy wonder how many barrels get pitched when they really need a good deep cleaning..
 
 Exactly.  And how do you have a meaningful discussion around the topic without it just being speculation.  Without the pictures from the bore scope, this thread would have not been as useful.
Bob
If everything seems under control......you're just not going fast enough

Re: 6mm CM Barrel Replacement

Reply #27
i was going to start a thread on this a few weeks ago but figured i would get laughed off the forum... lol... so i called jerry instead to see if he thought i was crazy... lol
Grant

Re: 6mm CM Barrel Replacement

Reply #28
Just to jerk his chain, I told him he was crazy as a loon. Had him goin for a while. 😂 Told him it was a good thing he didn’t post that cause he would get laughed off the forum. Then I had a pang of conscience and told him the truth. Grants experience was a good reminder for me though and I’m glad he shared his findings.

I’ve been looking through some sort of bore scope since 2016 when I bought a Larry Willis. Shortly after getting it I sent some pics of what I thought was a severely fire cracked barrel to a gunsmith friend. He laughed at me and said there’s nothing wrong there that won’t clean up! He was right and JB has been my friend ever since.

Re: 6mm CM Barrel Replacement

Reply #29
Thanks for the post and the pictures.  Very educational.
Live with honor and ride with courage. Be friendly to all those you meet.  But always carry a knife in your boot and a gun on your hip 'cuz there are those that don't think the same as this.