Deposits in bore causing loss of accuracy

[45stomp]

Hey cast boolit brethren.

I'm noticing a disturbing trend of streaks building up in the bore for the first few inches ahead of the chamber. There appears to be a corresponding loss of accuracy that accompanies this fouling. I'm wondering if anyone else has noticed this.

I'm using Eastwood powder, copper vein mostly, and pretty sure I'm cooking long enough. Minimum 400F, (tested with a thermometer) and minimum 20 minutes after wet out.
This is in 45 colt, with loads from mild to moderately wild.

Any thoughts? The deposits are a PITA to remove, more so than the minimal lead deposits I've dealt with from similar loads with conventional lubed boolits.

Stomp

[mehavey]

Using Shake`N Bake, I was having 1st-coat-coverage probems w/ Copper Vein.
(Took at least two coats)

Are you running one coat, or two?

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Earlier Post:

OVEN @ 400
Pure Copper Vein
Shake 5-8 min almost nothing looks like it's sticking
Bake anyway
Cycle 1: 30min Cold to finish
- Cool to RoomTemp

Shake again for 30-40sec. Total/rich coverage
Bake again
Cycle 2: 30min Cold to finish

[45stomp]

I'm coating twice. Single coat is thin, but nice coverage with 2 coats. Shake and bake.

Stomp

[Rcmaveric]

Prewarmed bullets helps a stubborn powder to coat better.

I have noticed deposit with PC bullets but they didn't affect accuracy any. Yes its a pita to clean out if you can. I cant get they deposit out of one of my 9mm and I don't feel like playing with harsh acetone.

Sent from my SM-N970U using Tapatalk

[charlie b]

I use Ed's Red formula for cleaning. It includes acetone so takes care of PC residue.

To me acetone isn't as harsh as many other solvents out there. MEK is another choice that might work for stubborn deposits of PC.

[Rcmaveric]

MEK is acetone in steroids. They make us wear respirator and those stupid thick chemical gloves when working with it. I watched a couple girls last month using it. They just got their nails done. The look on the faces when it dissolves their latex gloves then their nails started melting and popping off.

Sent from my SM-N970U using Tapatalk

[charlie b]

Yes it is. Works good as a paint stripper too.

[popper]

Acetone is absorbed through the skin and is hard on kidneys. Just be careful. Try some jacketed to remove the residue. If it is cured PC, very hard to remove and probably not completely cured. Try partial cure on first coat then fully cure second coat.

[prs]

The powder paints with metalic content are on my skeptical list. The good looks may be out weighed by abrasion and bonding to barrel steel. I had some deposits with a powder that has a gold metalic color, coated great and really pretty, but I tossed it. I did find a product that cleaned it well, it is a household product called Goo Gone. Apply with soaked patch, wait a few minutes and clean with dry patch. But, easier to use powders that work without bonding to barrel.

prs

[45stomp]

Thanks for the tips, guys.
I'll see if the Eastwood blue causes the same trouble.
Stomp

[GregLaROCHE]

Try a different powder to start to narrow down what the problem is.

[gnappi]

A wise viewer here suggested the mallet smash test on one of my bullets when I questioned my coverage and adhesion, have you tried it?
.

[Newboy]

I was getting some paint residue in my 9mm barrel when I started powder coating. Terrible to remove!

I went to a larger bullet (.358), and I stopped having problems.


Sent from my iPhone using Tapatalk Pro

[Tripplebeards]

I’ve never had this issue with Smokes PC. If it were me I’d try a different brand.

[45stomp]

Thanks for the suggestions guys.
Stomp

[Forrest r]

Ran into a similar issue with a 308w and coated bullets. When I started pushing the bullets 2600fps+ I started seeing black streaks/fouling in the bbl. I used bore-tech bore eliminator cleaner to get it out of the bbl, it did a fantastic job of removing the pc fouling.

What was more important way why did it happen to begin with? Narrowed it down to 2 things, the 1st being operator error. I was inconsistent with my pc coating technique. Along with unstable temps when pc'ing (winter/summer/wind/etc). Switched over to a pid controller and upped the cooking time to 20 minutes (15 minutes before) did wonders for getting consistent results with my pc coating's.

I was still seeing a little bit of black residue in the bbl (a lot less than before) after correcting my operator error/pc'ing mistakes. I like to use smokes john deere green pc and I believe I was seeing "friction" burns/small spots of black residue in the bbl still. I tumble lubed the pc'd bullet with a thin layer of 45/45/10 and haven't had the issue since.

There are no defects/rough spots in my bbl, any chatter can and will cause issues. The bbl I'm using for the 2600fps+/308w loads in a shilen select bbl that was bores scoped for defects before installation
I only had the issue when pushing the pc'd bullets 2600fps or faster in any caliber.
Pressure didn't cause this velocity did. 2600fps+/30,000+psi loads had issues. 2400fps/50,000+psi loads did not

I still check the bbl for wear along with how clean it is, bought this bbl to shoot cast bullets only. I don't like to do a lot of brushing cleaning in any bbl especially in the throat & leade area's at the chamber end of the bbl.
[IMG][/IMG]

Pictures are worth a 1000 words. The throat still looks crisp/shape edges as do the lands. There is also a small amount of lead streaking/build-up after the ends of the leade's. That is lead steaks from shooting traditionally cast/lubed bullets 2625fps, a couple more passes with a bore brush removed those streaks.

Don't know if any of this will help, just what I ran into and what I did to resolve what I was seeing.

[Petander]

An undercured coating is my worst nightmare.

It will bake in the barrel.

[igolfat8]

This will remove any PC or HT deposits!
https://www.midwayusa.com/product/2093155799