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Can you break in a barrel with light loads?

18 Oct 2017
@ 03:23 pm (GMT)

Thomas Kitchen

HI guys.
Just got my 6.5 rem mag back from Grant.
I need to fireform the brass I made, just wondering if I should follow break in procedure with trailboss loads.
I got 20 to shoot.
Might be a case of just check after each shot etc.


18 Oct 2017
@ 11:13 pm (GMT)

Warwick Marflitt

Re: Can you break in a barrel with light loads?
Hey Thomas. Ring or text Grant in the morning and ask him. Cool another one to play with. .... 6.5 magnus of Remingtus!!!! Sounds like a Geek god? Enjoy it mate.
19 Oct 2017
@ 03:24 am (GMT)

Bryan Webster

Re: Can you break in a barrel with light loads?
Realy, I cannot see what if any difference it will make, other than you may not see the grouping tighten as the bore gets treated. I would clean between each shot, for a bit at least.

When I broke in my 7mm Rem Mag with its Benchmark barrel I did not use weak loads but they were not full ones and it took about 15 rounds with cleaning between the first 5 rounds then every 5 rounds after that. It has 5R rifling and was well lapped so did not show much fouling from the start, but the groups tightend right up as the 15 shots were made.

I am interested in your experience with this rifle, keep us posted.
19 Oct 2017
@ 09:46 am (GMT)

Nathan Foster

Re: Can you break in a barrel with light loads?
You can Thomas, just a bit slower sometimes and may not give a full indication of fouling.

Take note that with the passage of time and learning, TF now have well established procedures and the barrels do not take much to break in. There will be a few minor burrs from chamber reaming but thats about all. To this end, we have to be careful not to take polishing too far. For example, the first few shots may produce heavy fouling and make us think that the throat needs harsh work. But what you may find is that the throat needs only very basic work and that after the first few shoot 'n' cleans, the fouling suddenly drops right away and that you may not defoul for another 100-200 rounds. In other words, take it easy on the throat work. Do what needs to be done based on what your eyes are telling you when observing the muzzle versus difficulty of copper removal, but do not go too far.

Otherwise, some full pressure test loads will be useful. You can intermix these formed cases with your current unformed foulers as tentative preliminary accuracy test loads while studying bore progress.

Am currently working through a similar process with another forum member. The goal is to take a Sendero and have it done and dusted in a few precise chess board moves based on the Accurizing book. But in this case, we are fast tracking for the sake of time / hunting seasons (rigid mount bed instructions from book). This versus the current internet banter about how the factory Remington's are very poor quality. The rifle has now had 9 rounds (unformed) through it and is already just under the MOA mark. It was purchased less than a week ago. The methods are slightly different to how you will approach this lapped barrel. Somewhat harsher, the intent and actions are more aggressive, direct. Hopefully this continues to plan. I could be wrong, there is always this possibility / reality but for now, we stick to the plan. In either case, the rules are the same - Address the fundamentals of the platform, then let the barrel do the talking.

19 Oct 2017
@ 12:00 pm (GMT)

Thomas Kitchen

Re: Can you break in a barrel with light loads?
Thank you guys and thank you Nathan.
I'll just follow your steps and let the barrel talk to me.
The videos have been a great help with understanding this more.

At the moment I only have 20 formed cases and the guns sitting back in the converted military stock.
Forming has been a lesson in itself, hopefully will just by some bertram brass when it becomes available.

This rifle is going to be a real honey to shoot with its no5 profile barrel.

On separate not Hornady just released a 6.5prc round 147grain at 2910fps think I'll beat it by roughly 100fps but none the less it's good to see something with bit more grunt then the creedmoor
20 Oct 2017
@ 06:17 am (GMT)

Bryan Webster

Re: Can you break in a barrel with light loads?
Nathan's post is right on. While I did not follow it exactly here is the link to the Benchmark barrels break-in. Note that their barrels are very smoothly lapped etc and I just used JB Bore Bright to do the throat even if they never mentioned it. Never went to town on it however.


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