Brass Buildup on Bolt

[rangeryo]

Hey guys, forgive me if this has been covered before but...

My Remington 700 has some pretty serious issues with brass buildup. There are two places where the buildup is occurring, the bottom of the bolt, which is clearly from the rounds in the magazine, and the bolt face. The buildup on the bottom of the bolt isn't too concerning to me. I'm sure this is due to excessive spring tension in my new AICS magazine. I'm betting that I could also resolve this by polishing or jeweling the bolt.

I am however concerned with the buildup on the bolt face. I've never seen this in any of my other bolt action rifles. I've noticed the buildup with multiple brands of ammo, so I'm sure it isn't a batch of bad brass or anything like that. I'm sure, that in a "precision rifle" this buildup, could potentially cause inconsistencies in accuracy, as the casing doesn't have the same contact with the bolt face with every round.

Does anyone know what causes this buildup, and if there is a way to correct it?

I'll post some pictures once I get home, if that will help at all.

 

[rangeryo]

After only about 20 rounds...

 

[thrusty]

Does seem like a bit more brass than what I typically see on my R700....especially after only 20 rounds. The brass shavings are typically from the extractor shaving off tiny amounts of brass, so maybe there's a bur on it that could benefit from polishing the extractor....is this a new gun or is this a gun that was otherwise showing typical amounts of brass and has all of a sudden started to build-up with brass?

I also see that brass on the underside of the bolt, and it is from rubbing the rounds that are still in the mag...pretty typical there.

I'm assuming that you were using only factory loads and not handloads? You seeing pressure signs on the brass anywhere? Sticky bolt?

 

[rangeryo]

I am using factory loads, and no pressure signs. This is also a new gun, which was purchased on black Friday 2012. It does have about 400 rounds down the pipe, but I've seen the buildup from the first box of ammo. I could try polishing the extractor, I haven't thought of doing that. I did shoot some steel cased ammo at one point, as I couldn't find anything else, and it's possible that it could have gotten worse afterwards.

 

[hdbiker1]

I see the same brass color on one rifle the I run a 0 chamber on and size my brass to the same. I just remove it with some solvent whenever I clean. I wouldn't worry about it unless you're getting shavings, then I would think about adjusting/tuning your extractor. You might check the headspace, it might be a little tight since it does it with factory ammo.

 

[drglock]

I once had a Remington 700 ADL 25-06 that did the same thing. I would just make sure that I cleaned the bolt face ever so often.

 

[MikeEzell]

The bolt face is rough as a result of the cheap factory finishing(or lack of) process. When you fire a round, it gets pretty tight in the chamber until the primary extraction cam breaks the seal between cartridge and chamber. During the initial bolt rotation, the bolt face simply turns against the case head, until primary extraction begins pulling it out of the chamber. Pretty easy to see how this happens when you think about what's going on during the extraction process that we take for granted. If not for that bit of primary extraction cam, we'd fight to get fired rounds from the chamber. Few factory Remingtons have enough from the get-go, and even less when trued without being timed to correct it.