Barrel break in and load development

[fuzzymarindave]

Sometimes the manufacturer will have a recommended procedure. I know that Weatherby has a method that they recommend for their rifles. Check with Savage.

 

[Point Man]

I am in the no need to break-in camp and that's after doing the break-in procedures many times before. It just lessens the life of your barrel more and burns ammo, especially with a 7 mag. Most can't even see the difference in accuracy, if there is any, because they simply can't shoot that well.

 

[JGRaider]

Barrel break in is a waste of time and components, IME.

 

[sveltri]

Barrel break in is a waste of time and components, IME.

Except how/when do you start load development knowing that barrel isn’t settled. I get not wanting to clean like crazy.

 

[Point Man]

Barrel settled?.....overrated.

 

[Pharmseller]

+1 on waste of time and components.

If it makes you happy, do it, but it will be like peeing your pants while wearing a dark suit.




P

 

[igethangry]

Did anyone answer the question of when you actually start working up a load after performing whatever break in procedure you follow? Do you send a predetermined number of factory rounds through the barrel first? Chronograph a specific load until velocities seen to stabilize?

I load for 223 now and am just getting into loading for 6.5CM and 7RM, but with the cost of components being substantially more for the larger cartridges I want to try to avoid wasting a bunch of money.

 

[JGRaider]

Barrel break in is a complete waste of time anyway.

 

[igethangry]

Barrel break in is a complete waste of time anyway.

So, do you just start load dev on an unfired rifle from the get? Your velocity/groups don't change after the first ~100 rounds? A 1-1.5 MOA load combo won't change after the initial barrel wear in? That's what I am trying to understand... I don't care about barrel break in unless not doing some form of break in is going to result in me having to redo load dev after 100 rounds... Should I just fireform 50-100 factory rounds and then start load dev?

 

[JGRaider]

I scrub the barrel clean and then apply Dyna Bore Coat to the barrel. I follow their directions, then start development. Works for me.

 

[fuzzymarindave]

So, do you just start load dev on an unfired rifle from the get? Your velocity/groups don't change after the first ~100 rounds? A 1-1.5 MOA load combo won't change after the initial barrel wear in? That's what I am trying to understand... I don't care about barrel break in unless not doing some form of break in is going to result in me having to redo load dev after 100 rounds... Should I just fireform 50-100 factory rounds and then start load dev?

Two types: There is the new barrel break-in sometimes recommended by a barrel manufacturer and then there is the second barrel break-in where the velocity may increase after 100-150 rounds. The new barrel break-in might consist of shot/clean regime for first 10-20 rounds depending on manufacturer. This is the procedure that some folks are talking about being a waste of time. Whether you choose to do this or not is up to you and but go ahead and work up a good load at the onset (or after 10-15 rounds) and then revisit the load for possible modifications after 100-150 rounds. It is best if you have a chronograph.

 

[WCB]

Barrel break-in doesn't hurt so why not do it.

Because in my experience it doesn't help and I don't want to spend the time and effort into it?

 

[Harvey_NW]

So, do you just start load dev on an unfired rifle from the get? Your velocity/groups don't change after the first ~100 rounds?

Yep, I start load dev on new barrel with new components, keeping 2 things in mind: 1st - the barrel could speed up by the 200 round mark, 2nd - pressure is usually higher with fireformed brass. If you're loading close to pressure with new components, expect to drop the charge on the 2nd firing.

A 1-1.5 MOA load combo won't change after the initial barrel wear in? That's what I am trying to understand... I don't care about barrel break in unless not doing some form of break in is going to result in me having to redo load dev after 100 rounds... Should I just fireform 50-100 factory rounds and then start load dev?

The precision usually doesn't change a measurable amount because the combo shoots how it will shoot, this is often misunderstood by small sample size and meaningless traditional load development methods. OCW, seating depth and powder or velocity nodes, and all the other things 3 shot reloaders look for don't actually exist and have never been proven to be statistically valid or repeatable, they're just small samples of random distribution of shots that fall within the true cone of fire. When you shoot 10+ shot samples these trends start to disappear because the group to group variability gets driven down.

My plan going forward will be to find a combo that shoots initially - use quality components with a bullet seated so boat tail is at neck/shoulder junction and shoot a 10 shot group at a mid book charge, probably 2gr below max. If it's not sub MOA, swap powder or bullet, repeat. Once sub MOA, I'm done. Finish loading the rest, dial everything in, and done. Once fireformed, shoot a short charge ladder in .5gr increments up to 1gr over book max from reliable source. Drop 1.5-2gr from pressure signs. Done, monitor velocity and brass. If barrel speeds up and pressure signs show up, drop powder charge to accommodate.

Here's an example, except I worked up to pressure and was 1gr below signs in high temps, so second firing was definitely spicy. Initial 10 shot group-


2nd firing test with sticky extraction-


Drop 1.5gr and get velocity data-


Painless for the win!

 

[doc holiday13]

break is 100-200 rounds. When new, wet patch and follow with 2-3 dry patches. Shoot 60 rounds. Wet patch to see if a bunch of copper comes out. If not copper filled, run 2-3 dry patches and shoot till another 40-140 rounds. Load 6 batches starting 1.5 grains below max. Go up in powder charge .5 grains. Measure all speed data and check for pressure signs. Don't proceed if you see pressure signs in one of the batches. Pick the powder charge beneath your pressure signs and mess with seating depth till your groups close up.