Another Barrel Breakin Thread

Breakin new barrels or not

  • Yes I do

    Votes: 15 31.9%

  • No I don't

    Votes: 32 68.1%
  • Total voters
    47
  • Poll closed .
When the manufacturer recommends it I pay attention. It is a pretty simple, easy process. Does my Vanguard shoot better because of it? I can't say for sure, but it is very accurate.
 
I do the One shot-clean. Two shots-clean. Five Shots-clean. Ten shots-clean process. Then shoot it like you stole it. Recommended by my riflesmith.
 
I always break my barrels in. Does it make a difference?. Can't say have never not done it. IMHO It makes a world of difference.To not do it, to me is foolish. To the OP. I have used that method for all my rifles and it shows when i shoot. I guess it's like when i got a new motor on my boat.A few would say break it in like you are going to use it. Full bore all the time. The ones that do that (full bore). Those are the ones in 5 years ,you see them cranking away on the motor to get it started,won't idle for crap. runs rough.
Break your rifle in the right way and see the difference in years to come
 
Engine break in is worlds different than barrel break in.

Most say you need to put 500 miles of low RPM driving on a new car before you romp on it.

Any new engine is broken in in as little as 1 mile.

All it needs is good high heat cycle (read high RPM) to seat the rings properly. After that, there is no more break in required.

Seating rings is a lot different than "seasoning" a barrel. If you have to "season" your barrel, it was not manufactured properly. To me, the MFG suggesting a break in is just another way they can cover their own butt in case you get one of the really bad barrels...
 
Plenty of manufacturers recommend barrel break in. When i read it was a myth from Gale McMillan i said the hell with it, i'll never waste the time to do it again.
 
Man - now I'll have to buy a new rifle so I can have one that's been properly broke in.;)

Did anyone notice on that break in procedure link that their recommended hunting ammo of a 308 with 24 inch barrel was 100 grains?
 
Did you also notice they recommend using a nitro powder? Which is a "ball" type double base powder that typically is higher pressure. I'm curious as to why that would be necessary. And it is NOT used in most factory ammo like they say. Remington uses extruded powders in most of their loads.

And their discussion on not letting the barrel heat up etc. That seems to be covering up the "stress relieve" heat treatment done to most good barrels.

Barrels are "quenched and tempered" in the bar and then machined. The hardness "as quenched" is about 50 HRC (in 4140 alloy steel) and is too brittle and hard to machine so is "tempered" down to HRC 32-40 (at approximately 1000º F). THEN, using proper, industry accepted metallurgical techniques, the "rough machined" part is "stress relieved" at approximately 950º F. (slightly less then the tempering temperature) which will not lower the hardness but will remove the "stresses" put in during rough machining. The barrel is then "finish machined" (light cuts and little tool pressure) to final sizes. Rough machining (heavy cuts at high tool pressures) WILL put in residual stresses that can relieve themselves when the barrel sees later heat (shooting). Sorry if I bored you with all this.... :p
 
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Jim243 noted in a thread IIRC that most break ins are referring to smoothing out burrs in the barrel that was cut with a reamer with a dull throater, which is correct. Due to the dull throater instead of cutting clean sharp rifling it smears a burr up on the down wind side of the rifling. On most custom hand lapped barrels this isn't necessary as most barrel manufacturers tolerances are much tighter than factory. So how dull they let the throater on the reamer get is much less so to speak than factory.

http://www.6mmbr.com/gailmcmbreakin.html
 
I'd like to hear a metallurgist comment on the "don't allow the barrel to heat up" during "break-in" and the "home registration point"...

I can't find that terminology (home registration point) anywhere...

I'm calling BS on that one. I can't see any reason that heating up a barrel during break in causes any sort of permanent damage. How does the steel know whether it's the first ten rounds heating it up, or rounds 850-860?

Any metallurgists out there?
 
I'm no metallurgist but thin barrels are subject to change in POI when heating up. Thick contours such as MTU/AMU M40/M24 aren't really that subject to it. Frank Galil has a video of him shooting a 20shot group at 200yds with no change in impact in hot conditions. Now i can't say that i think he would be able to do that with my 700 KS Custom with a very thin sporter barrel on it.

I would call BS too i don't see how the barrel heating up would physically damage it. I mean reasonable heat, not continuous which can indeed damage the barrel. It's kind of like break in if someone could explain to me how running a patch with solvent or a regular patch through the barrel physically alters that barrel to shoot better i'd be sold
 
When i read it was a myth from Gale McMillan i said the hell with it
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Roger that. A point he added was that people use abrasive paste and other "remedies" to "accurize" the barrel. I would think the manufacturers would do anything they could to make their barrels more accurate and get an edge on the competition.

My break in process consists of a good cleaning once I get it home, shooting a factory box, then cleaning. Then I start to develop handloads.
 
I'd like to hear a metallurgist comment on the "don't allow the barrel to heat up" during "break-in" and the "home registration point"...

I can't find that terminology (home registration point) anywhere...

I'm calling BS on that one. I can't see any reason that heating up a barrel during break in causes any sort of permanent damage. How does the steel know whether it's the first ten rounds heating it up, or rounds 850-860?

Any metallurgists out there?

tobnpr
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Yes, I'm a retired metallurgist (for a heavy duty transmission company). See my post above. What I was trying to say (and maybe got too long winded) was that if the barrel is not given a "stress relieve" heat treatment during processing that heating it up from firing it can cause your point of impact to move because YOU are in fact NOW doing that stress relieve and the stresses from machining still in that barrel now relieve themselves instead of during manufacturing like they should be.

HOWA doesn't want you to heat up the barrel (which is NORMAL when shooting) and see your point of impact moving all over the place. I would say heat it up and then it's done moving! Heating it doesn't damage it. It just "stabilizes" it really.

My break in process consists of a good cleaning once I get it home, shooting a factory box, then cleaning. Then I start to develop handloads.
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This is mine also. :D
 
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Hell after finally telling myself "hey it's metal there's not much your going to do that will honestly hurt the barrel/rifling." hehe i don't clean until degradation in accuracy and as stated earlier don't break in at all. Same goes for my ARs right now. I bought tough equipment i'm going to run them hard clean them in the down time. Tired of spending so much time worrying about components that i bought in the first place to be extremely reliable.
 
Break in?

I checked yes but what I've done on my last 2 new rifles -Rem Mdl 7 .243 and SA NM M1a - clean barrrel, fire a couple of rounds, clean with solvent and brush then patch clean, 2 rounds repeat, for 10 rounds total. Then I shot 10 rounds at a sedate pace then cleaned. I've since cleaned after each trip to the range 40-60 shots each time through .243 and 20-40 through M1A.
I figure thats more like a final polishing. Its better than trying to use that polishing or lapping stuff some recommend. It also keeps me shooting at a more reasonable rate than just whamming away.
Most importantly I guess it just make me feel like I'm doing something to make it shoot better or last longer plus it gives me benchmark to compare what kind of copper fouling builds up down the road.
 
I do, but it's more of a holdover than anything else. Hammer-forged or button-rifles barrels should need very little in the way of break-in, the bores and grooves are so smooth already.

Hammer-forged barrels are not stress-relieved after manufacturing. If you heat them up, they go all over the place, and it;s always nice to have a straight barrel, for appearance sake if nothing else.
 
Hammer-forged barrels are not stress-relieved after manufacturing. If you heat them up, they go all over the place, and it;s always nice to have a straight barrel, for appearance sake if nothing else.
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In a video I have seen them straightening barrels after hammer forging. If they hadn't been stress relieved (and purposely warped) there would be no need to straighten them would there? I have never been in a rifle factory but I did see that video. I don't know if they all do that but I know they did. I'd better not say for sure it was Sako but it was a well known rifle manufacturer and it was years ago... The long steel bar stock was hardened and tempered before any work was done. :confused:

They all may not stress relieve them after hammer forging but they should...


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