New Barrel Break-in And Cleaning Methods

There is nothing wrong with bronze but bronze will give you a false positive with copper solvents and with some powder solvents. Not an issue with BT nylon brushes shown above or with Iosso Eliminator brushes.
Thanks. I was curious if the bronze could be over aggressive. I have been using bronze for years and wondered if I could be causing damage. I will give nylon a try!
 
I'm building an AR in 350 Legend specifically for plinking and hunting predators, using cast bullets. I chose 350 Legend, because of the AR calibers, it seems like a very good choice for cast bullet use.

I just slugged the new barrel. It was hammer the slug (tight), then push by hand, then hammer again, then push by hand, then hammer yet again, and then the slug fell out. (It's a relatively cheap "AR Stoner" barrel from Midway) So, several tight and loose spots in the barrel.

Sounds like I better hand lap the barrel, right??

Vettepilot
 
I'm building an AR in 350 Legend specifically for plinking and hunting predators, using cast bullets. I chose 350 Legend, because of the AR calibers, it seems like a very good choice for cast bullet use.

I just slugged the new barrel. It was hammer the slug (tight), then push by hand, then hammer again, then push by hand, then hammer yet again, and then the slug fell out. (It's a relatively cheap "AR Stoner" barrel from Midway) So, several tight and loose spots in the barrel.

Sounds like I better hand lap the barrel, right??

Vettepilot
Tubbs Final Finish if they make it in that chambering. If not a neconos kit should work - same process.
 
Thanks Len! Your method fits perfectly with insight I got from Proof Research a couple of years ago. They told me that usually, they only see problems with too much cleaning. They told me to clean after 100 to 300 rounds IF my groups loosen. I told them that it took about what you recommend for break in, and the barrel became VERY easy to clean. They said that they take great pains to produce the finest barrels.
 
Lots of good methods reading this
I have a question.
Pros and cons of bronze brush vs nylon brush?
Not only barrel break in but afterwards as well?
I use bronze brushes as a first step with a carbon cleaner. I happen to mostly use C4 but Kroil works well. I make sure there are no copper cleaning agents in contact with the bronze brush as it will shorten the life. I make a 20-25 stroke pass and patch it out with copper remover. I have done this for 20 or more barrels in the past 5 years and the barrels will hold the original precision until the usual life span. Do make sure you use a good bore guide and a rod with a freely rotating bearing handle. Most of my fellow competitors clean with bronze brushes.
 
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The same methods I use for my BR rifles, I use for my LR hunting and ELR stuff.

No break in, just shoot and clean as normal. It will take 100-150 round for the barrel to settle in no matter what you do.

Clean with Montana extreme copper killer. Its the best carbon solvent I have ever used. They just advertise it for copper, which it works well on too. It will not harm a barrel.

2 wet patches, 10 strokes with a bronze brush, repeat until clean. Usually only 2 or 3 times.

Clean every 50 rounds or so. A little less or more is fine, but don't go hundreds.

Replace brush often, it has to fit snug.

Finish with one patch wet with Montana extreme bore oil, follow with 2 dry patches with the bore guide removed. Then swab chamber with a shotgun patch over a .410 bore mop.

Simple.
 
Say you have a shooting session of 10 rounds or less --- Do you run a couple of wet patches and then dry patches to remove some of the carbon or leave it alone ? I'm not talking about a cleaning --- just about removing some of the carbon build up ?
 
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