To brush or not to brush

[kwaynem]

How many run a brush down the neck of your brass before loading? I have tried both just curious what others think I have asked a few other members by text and it’s pretty much split

 

[Forgalspop]

yep

 

[rockchalk06]

If I trim/chamfer/debur then run the cases through corn cob, I don't. If I trim my bolt stuff and don't use corn cob, I do. I have a nylon 45 cal brush I run in and out to make sure no burs are left

 

[rickm]

nope

 

[magna19]

yes and no

 

[swampratt]

yes.
I anneal every time also but you did not ask about that.

Some of my Pistol cases do not get brushed.

 

[GC7]

To lube inside the neck or to clean any burrs?

 

[Ready_fire_aim]

I don’t. Should I?

Maybe for rifle stuff seeking maximum consistency. Pistol stuff? Nah

 

[mr ed]

If I shot the ammo and picked it up. No! If it was "range finds" then Yes! as it may have mud , insects or other trash inside.

 

[swampratt]

I looked at what many different benchrest shooters do in the brass prep area.
I read an article where a guy brushed the necks inside with a worn bore brush and 0000 steel wool and also had a plug of that wool in a socket and after trimming and chamfering the case it got ran into that spinning socket to slick it all up.

He said accuracy improved.
I was kind of new to reloading and was searching for any extra edge.
I did notice the bullets after I seated them would leave a bit of copper colored sparkles of gilding metal around the mouth of the brass sometimes.

I found a VLD chamfer helped that out and I decided to brush necks at the same time.

What I noticed is no more copper sparklies.
I also noticed my seating pressures were more consistent.

I was measuring Neck ID at the time with my dial calipers inserted into the case.
I thought HHHMMM If I spin this case while measuring I can feel the surface roughness.

SO I felt surface roughness of the case necks after cleaning and they were very rough.
I decided to brush the neck and feel again and was rewarded with a much smoother feel while spinning the case with my fingers and measuring with the calipers.

I thought smoother neck ID should treat my sizing stem much nicer.

It did and I then checked neck friction after sizing and then brushed it and checked again.

It is an eye opener.
Along those same thoughts I was expanding pistol cases for cast bullets and noticed that copper colored sparkle stuff after flaring the case mouth.

I removed the flaring stem from the die and noticed it had machined lines in it so It got polished to a super chrome finish.
Slicker than water on ice.
I no longer got any copper sparkles on my case mouths after flaring.

Now I ended up taking a Tavia mini valve spring pressure tester and placing my case with bullet on it and seating the bullet in my press and watch seating forces.

I did change the gauge to a smaller numerical scale so I could really see each pound of force needed.

I will leave a video for you to watch and you can see how much initial force is exerted and how much force to just continue to seat a bullet and if you watch the entire video you will see one bullet being seated and pressures jumping around.

Brush the necks and use a VLD chamfer and eliminate the jumping around and it will also aid in initial starting force.
Here is the video.



Now i took it even farther and wondered if seating forces really mattered.
Would different seating forces result in different pull forces once the bullet was in all the way.

I drilled a hole sideways through a bullet above where it was in the case and then seated it.

I then took a piece of wire and ran through the hole and clamped the base of the case in a vise.
I took my pressure gauge and ran the wire around it so when i tried to pull the bullet from the case it would compress the anvil in the gauge and give me a reading.

I found if it took 80 psi to seat it also took 80 psi to pull and 40 psi to seat took 40 psi to pull.

Obsess much? I see it as eliminating every variable that you possibly can and if you miss a target it was the shooter most likely.