Barrel break in and fire forming these days

HuntingBronco

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Love to get some input. I have 2 new 300WM to develop loads for. Goal is to shoot 205 berger hybrid elite hunter over H1000 lit by CCI250, starting with virgin Peterson Long brass. To conserve ammo, can I clean barrels and go straight to ladder or do I have to break in barrels? Am I kidding myself trying to shoot virgin brass? I have realistic goals of shooting 1 moa, but would like pretty good ES/SD.

1. Just get to shooting ladders in both guns? OR
2. Break in barrels and fireform brass with different components ? (I have some 150gr 308 bullets/other powders)

Thanks for your insight/thoughts in advance.

PS - rifles are nothing special - off the shelf T/C Compass II and Savage 110 variant.
 
If you have a magneeto speed, I broke in the barrel with about 10 shots on my RUM barrel just to get an idea of velocities. Started low and 1 gr increments up. I cleaned every third round back to steel. I wanted to see how high I could work before pressure signs.

Topped out and then backed off from there a few grains. Loaded up in .5 gr increments to find the load and was pretty comfortable knowing velocities and a good load I could go hunt with. Knowing the barrel would speed up after 50-100 rounds. I then started playing with other bullets, powders, and brass just because I like to fiddle. I worked through all the cases before adjusting/testing fire formed differences.

245gr Berger at 2832 FPS with good ES. Not the fastest, but cold bore and follow up are on.
 
Yes, one of the really not at all agreed on topics is rifle barrel breakin. Even the barrel makers and custom rifle builders don't agree. If I remember correctly an old article written by Gale McMillan even postulated it was a way for barrel makers to sell more barrels. I hope I am not mis-remembering.

Some people think you break in custom barrel differently than factory, etc. I think I have more than one 1/4 MOA gun but I am not good enough both reloading and shooting to see that commonly, so keep that in mind. I do tend to agree with comment about not using high quality ammo for break-in period, and I consider it a period. But if you have virgin brass it is a great opportunity to get it once fired.

In example I am breaking in a Sig 716i 308 and using some Australian ball ammo to do it. My method is kind of a hybrid of different methods. First time, swab the bore to make sure no oil or debris, fire between 20-50 rounds, never letting barrel get too hot (don't measure temps yet, device in transit). Then I clean but really focussing on carbon. Even in my older guns if they are shooting good groups I ignore copper. After the first time, I do the same thing one more time and I am done. So many people still believe in the shoot 1 clean shoot 1 method I have not gone all in on no breakin. But I think the other extreme is not the best use of my time, ammo as well as barrel life in barrel burners and I do not think I am risking my investments. One commonly agreed upon idea is that each time cleaning you are risking damage that can deteriorate the accuracy we all seek, so I think that also support my method. Or maybe I am just lazy and trying to justify it.

I do have a borescope but limited experience with it. In general I am not sure I am better off seeing a bunch of things in the bore I don't fully understand. The custom barrels look much better than factory but it has not always translated in accuracy.

Again, this is not a recommendation or anything I have a ton of data to support, it's just what I do.

JB
 
With the Peterson's .300WM Long brass (awesome choice), the fire forming is minimal compared to normal .300WM brass.

I don't break in custom barrels. And I barely break in factory barrels.
I say load a ladder and go for it.
 
I used to do the fire one and clean to steel for 5 shots, fire three and clean to steel for 3-5 cycles. Accidentally ruined a throat, by getting a patch stuck (smith scratched it up getting the patch out), and had to rechamber. That ended my break in ways.

I think that cleaning/break in regimen might be okay for factory mass produced barrels. For High end barrels, I now clean initially to remove debris and oil prior to shooting and clean after the first ladder to develop a load and then only as needed. My rifles seem to shoot better "dirty", so I only clean to steel if accuracy takes a slip and carbon removal doesn't seem to work. I clean carbon at the end of the season regardless. And I clean carbon if I notice a pressure/speed spike, if I was in a really wet/dirty environment, or if accuracy degrades.
 
I like to have as accurate a load as possible during fire forming, and have had some fire forming loads with good brass that were extremely accurate, as good as accurate reloads. Sometimes I even hunt on those first hundred or so fire forming rounds because I shoot all of those (except the one or two at an animal) through a chronograph watching for it to level off. So I am confident in my speed and accuracy. tight now I have one rifle I am fire forming brass for with cheap components and one that i am using the good stuff in, reason was parts availability for both.

Do what ever makes sense to you.
 
I'm glad to see these responses. Picked up a couple of rifles with hand-lapped barrels and was loathe to spend powder and primers doing break in.
 
I think the machining processes are so good anymore, that you would be hard pressed to find a custom barrel that "needed" to be "broke in" by alternating shooting and cleaning it. I think shooting it is the true "break in" to what it is purposely built to do.
 
Good point about machining processes. Maybe it's like cars. Anybody remember car or motorcycle engine break in instructions about max rev's, not sustaining one speed too long but changing it up and down, etc.? Don't have those anymore either.
 
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