Copper fouling location in barrel

What caliber and what MV? You may just slow it down a bit.

It's a 30-284...

With the 165gr interlocks, I was testing h4350 charge weights from 57.4g-59.0gr and had velocities from 2925 to 2990.

With the 180gr Speer hot cor, I was testing h4350 charges from 56.8 to 58.4 getting speeds up to 2875 I believe.
 
Might be worth a try to shoot some Sierra match kings for awhile, as a test.. Clean the fouling out and shoot a different bullet for awhile.

I have a number of Mullers, good luck with them so far. good luck.
 
Ok back down to a lower node and see if the copper fouling decreases. Many will shoot better at the lower node anyway.
 
Its pretty obvious that really rough throat is your problem, high or low node I seriously doudt its gonna matter untill your rough throat is addressed.
My 2 cents anyway
 
Its pretty obvious that really rough throat is your problem, high or low node I seriously doudt its gonna matter untill your rough throat is addressed.
My 2 cents anyway

Agreed. I just didn't know higher pressure could make it worse. I guess it make sense though that the harder you slam that bullet into the lands the more it might strip off
 
I mean you can try it but I think its a waste of time as far as trying to mitigate the copper fouling.
Before I did anything I would take care of the rough throat problem because if you dont you will never know if that is your problem with the flyers and you will just be chasing your tail wondering.
 
Yup I agree. I've done enough chasing my tail to want to avoid it.


Here's a few pictures of the throat now, after cleaning and giving it some JBs. A tight patch on a nylon brush with JBs. About 30-35 strokes in the throat. Repeated once with a fresh patch and JBs.

I'm not sure what the uneven almost pitted look is about. But, those lands are still really rough even with ~125 rounds down. It looks the same as the last time I JB'd it.

I think I'll probably go the tubbs route. I emailed him and he said he'd just do the TMS bullets, which is the grit #3. He said to shoot 7-10 of them initially and then a few every 300-400 to keep it in good shape.
 

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Appears to me if you put your original pics next to the ones you just posted theres a vast improvement. I would just shoot the thing now and see how bad it coppers. Understand you may not have to get the throat with every little machining mark out a borescope makes those maching marks look alot deeper than they really are.
 
Looking at your pics it appears the reamer had some very fine chips out of it, that reamer either needs to be reground or thrown away.
 
Looking at your pics it appears the reamer had some very fine chips out of it, that reamer either needs to be reground or thrown away.

Yea he said it was 40 years old. Why should I have to ask if his reamer is in good shape? Kinda ridiculous.

It does look a lot better than when new, but these pictures are after 125 rounds and the last time I shot it it coppered up horribly. I've used JB on it before with no improvement.

The only minor improvement I saw was after using a snug fitting maroon 3m pad on a brush and short stroking the throat. I know that sounds nuts, but I've used that on other rifles and it's worked well. I just didn't want to keep going on it because there is the possibility of easily screwing it up doing that.
 
Wow, 40 years old is ridiculous!
I dont know i just don't like putting impregnated bullets down a perfectly good barrel. However much it takes to clean the throat up that way will take just as much out of the whole barrel which will open up bore and grooves.
Personally I'd set the barrel back with a GOOD reamer, but thats me or I'd tell the smith to make it right
 
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