Why factory ammo for barrel break in?

[RidgeTop]

Asking about barrel break you'll get 100 different responses.

I don't do any break in. If it's a shooter it's a shooter. I've never had a barrel settle and shoot better groups after so many rounds down it. I'm not shooting F class, keepnin mind. Proper load development will allow for the barrel speeding up after 150 plus rounds. That's a lot of shooting for a big magnum.

Shoot it and have fun! If you're doing load work up, do a proper OCW to account for velocity swings.

What's OCW?

 

[RidgeTop]

For good results, always follow the barrel manufacturer recommendations.

 

[LongWalker]

What's OCW?

The Optimal Change Weight method for load development.

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I started using it when I first started reloading as I only had 100 yards so not enough range for a good ladder test. It's worked so well for me I've stuck with it. I've never had an issue with a load that once I confirmed at 100 and 300 I couldn't walk out to 500, 800, 1000 consistently.

 

[B P Shooter]

Should you ever buy factory ammo and plan to re-use the cases for reload, buy as many as you are able to , so as to have the same lot number (hopefully, check lot number on box) for the cases. ie; buy, say 200? Doing so, hoping the cases are oh the same factory stamping.

 

[GLTaylor]

I loaded light loads for 458 Win Mag (45-70 loads) and didn't use magnum primers. I got a lot of unburned powder, burning powder blasting out of the barrel and charred powder residue in the barrel.

The savings on primers wasn't worth the wasted powder & the mess I had to clean up.

Like I said earlier. It doesn't always work. Let your rifle tell you. In your case, the 458 definitely didn't like LR primers. It told you so.

 

[cabelasken]

I've got a new 300 WSM build in the works and have already assembled all the components dies, projectiles, etc (save 215M primers) and started looking for factory ammo for barrel break in when it eventually shows up.

Started looking for factory ammo and as expected not a ton of choices available and not cheap. To boot the Norma bond strike which is the most plentiful doesn't get glowing reviews for accuracy.

That got me thinking why not just use quality components I already have a just do a middle of the road load for the first 25 or so and then start load development.

I'm thinking and hoping I'm just stuck behind the curve and most folks already use this option. I use the same style load to fire form brass after barrel break in already so there can't be some magic to factory that makes it the best choice for a new rifles first shots.

Or is there......

I've always used long for caliber bullets to get as much bearing surface against the barrel to maybe accelerate the break in and shorten the amount of shots needed. My 300 WSM needed 150+ shots before it settled in with initial groups being over 1 1/4" and by 150 rounds was below 1/2". This was with a shilen SS select barrel.

 

[2buffalo]

This is the only reason to buy factory ammo....for the brass....if itnis good brass. But buy enough (5 boxes of the same lot) to get your 100pcs of brass you will be using.

If you buy 5 boxes of the same lot does that mean that the brass that went into making the ammo was the same lot of brass? I have never really thought about it but figured you may know.

 

[lancetkenyon]

If you buy 5 boxes of the same lot does that mean that the brass that went into making the ammo was the same lot of brass? I have never really thought about it but figured you may know.

Supposedly....
Just like lots of powder, bullets, brass, primers.
All SUPPOSED to be from a single run, meaning HOPEFULLY they are consistent.

 

[2buffalo]

Supposedly....
Just like lots of powder, bullets, brass, primers.
All SUPPOSED to be from a single run, meaning HOPEFULLY they are consistent.

I was just curious. Seems like in a mass production loading environment they wouldn't put the effort into making sure everything matched up. For example I bought a box of Nosler ammo to start shooting a new build because I didn't think I would have components in time. Loaded them in my new rifle roughly 1/3 of them were fine, 1/3 had hard bolt closure, and 1/3 you couldn't close the bolt. I'm not sure if it was different lots or terrible QC from the same lot of brass.

 

[lancetkenyon]

Honestly, if you have a good custom rifle, and it doesn't shoot well within 30 rounds, change something. No way would I pursue a combo that didn't shoot sub 1/2 MOA within the first 18 shots from a new barrel with just a quick charge weight test. Not even joking a little bit.

If it takes 100-150 rounds for a barrel to "settle down" and shrink groups from 1.5MOA to .5MOA, there is something wrong. Either you didn't find the right jump initially and had to erode the throat to get the jump it liked, or had a crappy lapping/chamber job, or something.

I have had numerous rifles that put shots 4-6 into .2s (1-3 were for sighting in).

 

[QuietTexan]

I see it now

 

[2buffalo]

Who's talking about groups getting smaller? It's a verifiable fact that velocities change significantly for a period of time, who's actually seeing group sizes change?

Waveslayer said he can tune a load in a new barrel that handles a 150FPS increase, he's the one who brought up group size changes?

Post 48

 

[RidgeTop]

I bought a set of lapping compounds of 3 different grits. A glass slide was included to roll the bullet in the compound before loading. Once loaded, firing the bullet would lap the barrel. I have not used it but think it is a good idea - possibly on a heavily fouled barrel.

 

[MKWas]

Like I said earlier. It doesn't always work. Let your rifle tell you. In your case, the 458 definitely didn't like LR primers. It told you so.

Yes. fighting reality is a losing proposition.