Gunsmithing Cartridge quality for barrel break-in

[Sugarbug]

I know there's a lot of argument about barrel break-in, so let's forego any discussion and just assume that I'm right and it's something you should do.

Now that we're all correct, I was wondering if cartridge quality is of any concern. I know guys that won't let anything buy handloaded match rounds touch their barrels. But is that necessary for break-in? Can I go buy a box of cheap rounds to fire threw the barrel or do I need to use my actual rounds?

I apologize if this is an amazingly asinine questions, but please humor me.

 

[T2CH]

You know, to be honest, I've never heard one way or the other. And I don't think I've ever seen this question asked. I think most use their match ammo because that's all they have.

 

[maccrazy2]

I would start with what I intend to shoot. Barrel life is finite so why waste it.
Also same answer for questions about practice ammo.

 

[pawprint2]

FM 23-10 agrees with Sugarbug regarding break-in. Although no mention is given regarding the type of ammo one should use. As the barrel will be cleaned after each round, the "make and model" of the bullet may only have an effect on the lead of the chamber. For one that is going to properly break in a barrel, the time and trouble is worth far more than the few dollar difference between "cheap ammo" (if there is such a thing anymore) and match grade. Years ago in a European publication, some bench-rest shooters did some testing on the lead angles and breaking, they concluded jam seating with mid power loads, building up to full powder loads (at all times jam seating) had the best effect on the steel. The article was accompanied by some electron microscope photos etc. Interesting as hell, but the effect was so small, I don't think it ever caught on. So I guess, my two bits worth is, it doesn't make much difference, however; if you buy match ammo, you'll have good once fired brass when you're done.

 

[DAVETOOLEY]

I know there's a lot of argument about barrel break-in, so let's forego any discussion and just assume that I'm right and it's something you should do.

Now that we're all correct, I was wondering if cartridge quality is of any concern. I know guys that won't let anything buy handloaded match rounds touch their barrels. But is that necessary for break-in? Can I go buy a box of cheap rounds to fire threw the barrel or do I need to use my actual rounds?

I apologize if this is an amazingly asinine questions, but please humor me.

The price of the ammo has nothing to do with the process. It's an abrasive process so any bullet works. I take my loading press to the range with me. I use the time to establish a max powder charge, seating depth with several bullets and powder types.

 

[Sugarbug]

Good idea, Dave.

 

[E. Bryant]

I've done break-in and functional testing with some of the random left-overs from previous load workups. If something doesn't work (such as a starting load that is well under the pressure limits of the round), the leftovers get set aside and eventually end up shoved to the back of the ammo cabinet. Use your brain, obviously - don't start with those abandoned loads that were a couple grains over the max book limit, shoved deep into the lands, and cratered primers the last time they were tried.

All that being said, how many rounds are actually necessary to break-in a barrel, and when does its "real use" start? To be honest, with a new rifle, I'm putting a few rounds downrange to obtain and confirm a zero, and then it's pretty much game-on from that point. Each to their own, of course.

 

[JB02]

To be honest, with a new rifle, I'm putting a few rounds downrange to obtain and confirm a zero, and then it's pretty much game-on from that point. Each to their own, of course.

^^^ Well said! ^^^

 

[pawprint2]

For those that believe the U.S. Army have learned a thing or two regarding weapons over the years, FM 23-10, 2-12:
d.

Barrel Break-in Procedure.

To increase barrel life, accuracy, and

reduce cleaning requirement the following barrel break-in procedure must

be used. This procedure is best accomplished when the SWS is new ornewly rebarreled. The break-in period is accomplished by polishing the

barrel surface under heat and pressure. This procedure should only be done

by qualified personnel. The barrel must be cleaned of all fouling, both

powder and copper. The barrel is dried, and one round is fired. The barrel

is then cleaned again using carbon cleaner and then copper cleaner. The barrel

must be cleaned again, and another round is fired. The procedure must be

repeated for a total of 10 rounds. After the 10th round the SWS is then

tested for groups by firing three-round shot groups, with a complete barrel

cleaning between shot groups for a total of five shot groups (15 rounds total).

 

[insight3b]

In a new barrel/new rifle I use once fired LC MG cases with a start charge of the powder I have the least of with the cheapest bullets I have on hand. I use it to get on paper and break in but its more important to me to have the brass for the next trip when accuracy testing actually begins. Before using MG fired LC I made sure that I used brand NEW brass but over the years I have concluded that it matters as much as concentricity pertaining to small groups on paper