Test-Effect of Brushing Necks vs Graphite vs Both on ES

[Savage 12BVSS]

This is going to come across as sacrilege but I don't clean my brass at all. Haven't for 10 years. After annealing and resizing (I use the full length RCBS S type Bushing die and an expander mandrel) they are relatively clean. Once you put a little lube on them a decent amount of the carbon wipes right off. They are certainly clean enough to see defects in the brass, which is all I care about. I just never found it to do anything for me other than make the brass look good and consume time.

I've been afraid to admit this same thing about cleaning cause you see so much posted about brass cleaning and tumbling that it seems the only correct way. Now this is the second poster to say this right out for the world to see and know, so I'm coming clean (pun), I haven't cleaned brass anyway but hand for 19 years. The way the gunsmith who mentored me taught me, worked good for me and sure never hurt my accuracy at all. Won't get into the lubing technique I was taught but the lube removes all carbon when wiped off, just a little oooo steel wool around the neck is it. Nylon brush in and out of necks twice, recently no graphite in neck's at all anymore. Forster die's without expander ball and latest addition from some posters on here lee collet neck die's and or sinclair expander mandrel's. Saved a lot of money on equipment.

 

[Bingoc]

Thanks for all of the effort and time to gather the data. I have brushed the inside of the neck and then dipped the neck into a jar filled with No 71/2 lead shot smothered in graphite to coat the inside and outside of the necks before I seat the bullets. Anyone ever try that?

 

[jrock]

When I use my bushing die, I dip the case neck into imperial dry lube with ceramic media to coat. Its on my to do list to do this same check. Might be quite a while before I get to it.

 

[Bob Wright]

Tag

 

[Rflshootr]

Thought I'd do a little test this morning and share the results with you guys. After watching the video Shawn Carlock posted about reducing ES and the video by Annealing Made Perfect where they brush out the inside of a case neck and then measure seating force, I wanted to see what effect both brushing out necks and graphite had on ES in one of my rifles. I normally don't do either of those things in my reloading operation.

So, I took my 6.5 Creed and loaded up a total of 40 rounds. 10 control rounds (C) that are loaded the same as usual 10 where I brushed the necks with a single pass of a nylon brush in and out (B), 10 where I applied graphite to bullet base (via the Imperial graphite dry lube little ceramic bead applicator deal) prior to seating (G), and 10 where I both brushed the necks and then applied graphite to the bullet prior to seating (Bg). I then shot them over my Magnetospeed round Robin Style (I.E. 10 groups of 4 comprised of 1 of each CBGBg), at 30-45 second intervals between each round, so that the effects of barrel heat would be similar across all groups. The results were somewhat surprising.

ES was lowest in the brushed only group and went in the following order. B<C<G<Bg.

When I throw out the highest and lowest velocity shot from each group the ES' were as follows:
B:20
C:24
G:28
Bg:53

It was also interesting to see how a 40 round group printed. The rifle will pretty routinely shoot groups in the .2s and .3s at 500. I shot at 525. The group ended up being just over 1 MOA. I suspect this is due to multiple things, zero/POI shift due to heat being one of them, especially since the 1st 8 rounds impacted in essentially the same spot. That said it was a pretty educational morning. I don't think I'll be using graphite.

I'm going to load up 10-15 more where I brush the neck out and see if anything changes from an accuracy standpoint. If they shoot the same then that was a pretty easy way to improve the long range potential of a load.

.2's and .3's at 500? Really?

 

[Chase723]

.2's and .3's at 500? Really?

Here's a few groups I shot recently. The steel is 500/525 and the paper is 100. Groups in the .2s are hard to shoot...even at 100. The .3s aren't too bad.

 

[Alex Wheeler]

This was a good test.
I want to make a point about testing. For example, I have used colloidal graphite for years inside case necks testing for accuracy. It will win the "reloading bench match" every time, it has by far the best seating force reduction and consistency. It has never shot best on target in every rifle I have ever tried it in. Pay attention to how things play out at the bench and on the chrony, but always listen to the target.

 

[Rflshootr]

Here's a few groups I shot recently. The steel is 500/525 and the paper is 100. Groups in the .2s are hard to shoot...even at 100. The .3s aren't too bad.

Good groups, no doubt. But there is a big difference between .2 and .3 and 2" and 3". You really should take that rifle to a registered IBS match and see how it does at 600.

 

[new2mud]

Good groups, no doubt. But there is a big difference between .2 and .3 and 2" and 3". You really should take that rifle to a registered IBS match and see how it does at 600.

I think he's referring to .2 and .3 MOA. Which he is demonstrating with the 1.5-2" groups at 500 yds.

 

[GLTaylor]

That would be correct! Measure the group, subtract bullet dia and divide by 5 for 500 yd moa

 

[Chase723]

Good groups, no doubt. But there is a big difference between .2 and .3 and 2" and 3". You really should take that rifle to a registered IBS match and see how it does at 600.

Roger. Sorry. I meant .2-.3 MOA. Not .2-.3". My fault.

 

[ShtrRdy]

Check the image in post #9. One can eyeball an average from the for averages from the bottom of each series, or formally calculate by averaging the four.

I ran these through my calculator

	average	sample STDs dev	sigma
Control	2737.9	8.22	7.69
Brushed	2739.9	7.85	7.34
Graphite	2759	8.07	7.55

Brush & graphite 2744.6 19.38 18.13

 

[Blancoalex]

I recently shared with fellow F Class friend using Mica to dry lube case necks after cleaning necks with bronze brush. He used small container with #9 shot. He does have a K & M strain gauge to test this. His before readings was 40-50 and then with Mica down to 10-20. He did not chronograph but it was neat to hear of the 66% reduction. He will shoot a match coming up. This is for his Lupua 6.5 Creedmoor brass.

 

[Wedgy]

Any chance that the graphite is affecting the bore , not just the seating force ? Even if you just coat the necks it will eventually make its way down the rifling over a period of time, probably lowering the velocity. I dabbled in moly, graphite, etc. but now only use HBN in a couple rifles and it definitely lowers the velocity ~40-50 fps but I am coating the bullets and the bore.
Thanks for the testing !