Powders and carbon ring in 20P

[AWS]

I have a really troublesome rifle that forms carbon rings rapidly. I'm leaving brass longer and it doesn't seem to help. My load is 40gr NBT and AA-2230 powder. Do you think changing powders, 3031, Benchmark, might make a difference?

My other 20P 32gr Nos HP and 2230 doesnt seem to have this affliction.

 

[Coyotefurharvester]

Primer change ?

 

[Hal]

I wonder if that 223 CFE would help you ?

Hal

 

[L.Sherm]

I have a really troublesome rifle that forms carbon rings rapidly. I'm leaving brass longer and it doesn't seem to help. My load is 40gr NBT and AA-2230 powder. Do you think changing powders, 3031, Benchmark, might make a difference?

My other 20P 32gr Nos HP and 2230 doesnt seem to have this affliction.

I use AA2230 in my 20P and do see any carbon ring any faster than other powders.

 

[jpx2rk]

I use AA2230 in my 20P and do see any carbon ring any faster than other powders.

Do or do not ??

 

[L.Sherm]

Do or do not ??

I do not

 

[L.Sherm]

Do or do not ??

Are you running the 40's slow? FPS?

 

[jpx2rk]

I'll have to pull my notes, etc. and post up my load data. I do remember getting some 3900+ and over 4000 fps during some testing, but I don't like those speeds and didn't go back there. LOL

 

[JLT]

I'll have to pull my notes, etc. and post up my load data. I do remember getting some 3900+ and over 4000 fps during some testing, but I don't like those speeds and didn't go back there. LOL

With the 40s, that's a little too spicy. Like, deprime-with-your-fingernail spicy.

 

[L.Sherm]

I'll have to pull my notes, etc. and post up my load data. I do remember getting some 3900+ and over 4000 fps during some testing, but I don't like those speeds and didn't go back there. LOL

Just curious because some powders can be dirty running light loads.

 

[searcher]

Yeah - no concern of having underpowered load there. I run Accurate LT32 in my rifle, though down around 3,500 fps. with the 39's and 40's. No carbon issues after running it many thousands of rounds. I tend to run my rifle around 150-200 rounds, if there are many critters, only running a bronze brush in and out maybe ten times with solvent and give about ten twists to attack any neck carbon with a non-rotating shorter rod with a chamber brush. A few more solvent patches, a few dry patches - and done for another 150-200 or until a thorough cleaning at the end of the day which entails more than a bore clean and a bolt wipe down. I consider that pretty high use on the barrel before cleaning, so the barrel isn't getting what most would call "babied" treatment. But this format has not allowed any carbon rings to form when I adhere to that protocol. There had been days when the shooting was so crazy, I just shot way beyond the point of needing a good cleaning. I did get carbon rings on those occasions, which then required a bit of abrasive paste to get it all out. I guess it also depends on how many rounds you are firing before experiencing these rings. There is also a big difference between a visible black ring and one which actually is elevated from the surface to a point where it does anything. Afterall, those rings start to form on shot number one, however lightly.

 

[SeabeeKen]

The OP needs to post his load info. Like L Sherm said, light loads can burn inefficient/poorly and cause much more than normal carbon. Hard to help without proper info. Some powders just produce excessive carbon also. Reloder 16 was one such powder in a few of my rifles.

 

[cb186]

N133

 

[AWS]

I load 25.5gr 2230, 40gr NBT. I get about 30-40 rounds before accuracy drops off and it's leaving a ring around the bullet.

 

[L.Sherm]

I load 25.5gr 2230, 40gr NBT. I get about 30-40 rounds before accuracy drops off and it's leaving a ring around the bullet.

Your load is about exactly what mine is with a 34 gr. bullet. Have you tried backing it down and seeing what happens.
Whats your 32 gr load?

 

[AWS]

26.5gr with the 32gr Nosler HPs the 40s are being shot out of an X-calliber barrel and the 32s out and f a Criterion barrel. Bothe appear to be pretty mild in my rifles I went a full grain over these but this was the most accurate load.

 

[jpx2rk]

With the 40s, that's a little too spicy. Like, deprime-with-your-fingernail spicy.

Looked at my notes/targets, those speeds I mentioned were for the 32g vmax with H335 powder. So not relevant to this discussion. LOL