• RIX Storm S3 Thermal Imaging Scope WINNER!

    Thank you to everyone who particpated!

    See the winner

Bore Paste vs. Lapping Compound...

RLinNH

Sergeant of the Hide
Full Member
Minuteman
Mar 23, 2019
355
208
I am having the "ring around the Bullet" issue, again. This time it's in a different caliber than prior. My Redding Competition seater hates my Lapua 139 gr Scenar-L bullets in .264. Anywho, on to my quesltion. I found via searching here where Erik Cortina uses Lapping Compound on his die and bullet in a lathe to try and alleviate the issue. He also states that Bore Paste can be used in a hand drill. I will be using a hand drill. I would like to use 280 grit lapping compound with a hand held drill. With this method, do you think the lapping compound is over kill? I always thought that Bore Paste was a lubricant...
 
"ring around the Bullet" can also be caused by too much seating force.
Are the bullets seating without difficulty?

Lapping compound should work just fine, me personally I would use a little finer grit.
 
"ring around the Bullet" can also be caused by too much seating force.
Are the bullets seating without difficulty?

Lapping compound should work just fine, me personally I would use a little finer grit.
I also thought that I may be using to much force during the seating process. I am doing my loading on an RL550, but I use it as a single stage as I don't trust the powder drop when it comes to my Long Range Precision cartridges. So, in order to get my .200 shoulder bump, my sizing die is set quite low. Hence, I am at cam over. I was thinking I am going to have to raise the sizing die some in order to get the over pressure off the seating die. It's something for me to try before I go the next step. The next step being lapping the sizing die...
 
Imperial graphite plus appropriate neck tension eliminates nose rings.
You're talking about Graphite powder, yes? So hit the inside of the sizing die with some brake cleaner, then apply some graphite powder? Seems odd to me as the Redding Sizing die has an internal moving piece. Hence, I did notice lube in that area... Then again, the powdered graphite would also be lubing that part. Interesting...
 
My apologies for being so dim, but inside the neck of the case prior to seating the bullet?

Yes - I use the Imperial neck lube application media, which is a bunch of little spheres with graphite on them.

What I do is dip the neck in the application media then wipe the outside of the neck to get rid of the graphite on the outside. You can charge/seat at that point, but I run them through the mandrel first.

 
  • Like
Reactions: Pvt.Donut
Before you charge the case.
This
I use graphite in a little make-up jar the wife gave me. It's about 3/4" deep and about 2" diameter with a good fitting lid. I filled it about 3/4 with #8 shot and some dry graphite lube. I replenish the graphite about every 1000 rounds. I use the white stuff and don't recall how small it is but it is SMALL (as in very miniscule diameter particles). After I reprime the case, I just dip the case mouth into the jar, give it a couple of twists and place it in the loading block. Makes all the difference in the world.
 
Does the mandrel come with the media?
No, you’ll need the separate die body to hold it and a separate expanding mandrel/turning arbor depending on your desired dimensions.

That said, a mandrel itself won’t eliminate the ring. It may if it changes the size of the neck, such as if it’s different than your expander ball leaves them, but if the mandrel and the ball are the same size already the mandrel will only make them more uniform between cases, not swing results wildly.

Lap the stem to sand down that sharp edge, provide an adequate chamber and deburr so the bullet slides in without getting scraped off on the case neck, measure neck tension and see how much interference fit between the bullet and the case mouth.
 
I also thought that I may be using to much force during the seating process. I am doing my loading on an RL550, but I use it as a single stage as I don't trust the powder drop when it comes to my Long Range Precision cartridges. So, in order to get my .200 shoulder bump, my sizing die is set quite low. Hence, I am at cam over. I was thinking I am going to have to raise the sizing die some in order to get the over pressure off the seating die. It's something for me to try before I go the next step. The next step being lapping the sizing die...
Is that a typo, .200 bump has to be. I don’t have an rl550 but how does the sizing die have any effect on the seating die?
 
Tried lapping compound once so far for what I needed It worked really well did not have to use with a drill or anything just rod , these plugs and a patch ran it through a couple of times got enough of what i wanted removed cleaner did the rest that was 2.5k round ago no problems since . Good luck finding the answer that works for you .
 
  • Like
Reactions: GrumpyOleFart
Hold a small piece of 600 sandpaper on the bullet on the contact area and spin the stem on it then lap it.

Measure a sized case neck vs a case with seated bullet to check your bullet retention.
Too much can goober up bullets.
 
Tried lapping compound once so far for what I needed It worked really well did not have to use with a drill or anything just rod , these plugs and a patch ran it through a couple of times got enough of what i wanted removed cleaner did the rest that was 2.5k round ago no problems since . Good luck finding the answer that works for you .

Huh?
 
  • Like
Reactions: Aftermath
Is that a typo, .200 bump has to be. I don’t have an rl550 but how does the sizing die have any effect on the seating die?
Yes. Typo. I meant .0200ish. More like .0150 of a shoulder bump with my set up. In order to achieve this on my press, I am in a cam over situation. The sizing die is seated very low. I am wondering if me camming over is also adding to my bullet ring. So, I have some 800 grit lapping compound on the way. Next time I seat my 6.5 Creedmoor Lapuas (no ring on my 130 gr Bergara Tacticals), I am going to lap the bullet seater, back the seating die off so that I am not in a cam over, and also use the Redding dry lube inside the necks. Crossing my fingers. And THANK YOU for all the recommendations.
 
Yes. Typo. I meant .0200ish. More like .0150 of a shoulder bump with my set up. In order to achieve this on my press, I am in a cam over situation. The sizing die is seated very low. I am wondering if me camming over is also adding to my bullet ring. So, I have some 800 grit lapping compound on the way. Next time I seat my 6.5 Creedmoor Lapuas (no ring on my 130 gr Bergara Tacticals), I am going to lap the bullet seater, back the seating die off so that I am not in a cam over, and also use the Redding dry lube inside the necks. Crossing my fingers. And THANK YOU for all the recommendations.
That’s still ten times too much bump.
Also, why would you cam over your seating die?
 
That’s still ten times too much bump.
Also, why would you cam over your seating die?
My before resizing size is 3.5675(using a comparator and headspace cartridge. I don't zero out, I just do the math). After I bump the shoulder, I get to about 3.550ish.

I need to have my seating die set that low in order to get my shoulder bump. That's as low as I want to go as the base of the die touches the ram...
 
My before resizing size is 3.5675(using a comparator and headspace cartridge. I don't zero out, I just do the math). After I bump the shoulder, I get to about 3.550ish.

I need to have my seating die set that low in order to get my shoulder bump. That's as low as I want to go as the base of the die touches the ram...

Man, that's way too much bump. You still need another zero in front. .001-.002 is what you're looking for, not .010
 
  • Like
Reactions: RLinNH
Man, that's way too much bump. You still need another zero in front. .001-.002 is what you're looking for, not .010
I just looked at the brass case prep sticky here again, and you sir are 100% correct. I have been doing it wrong with my 6.5 CM brass for 4 firings now...:mad: Well, thanks for not pushing my face in the mud at this embarrassing juncture.
 
My before resizing size is 3.5675(using a comparator and headspace cartridge. I don't zero out, I just do the math). After I bump the shoulder, I get to about 3.550ish.

I need to have my seating die set that low in order to get my shoulder bump. That's as low as I want to go as the base of the die touches the ram...
You’re way, WAY over sizing your brass. Like, WAY.
Your next thread will be, “why am I pulling the heads off my cases.”
 
  • Like
Reactions: RLinNH
You’re way, WAY over sizing your brass. Like, WAY.
Your next thread will be, “why am I pulling the heads off my cases.”
just looked at the brass case prep sticky here again, and you sir are 100% correct. I have been doing it wrong with my 6.5 CM brass for 4 firings now...:mad: Well, thanks for not pushing my face in the mud at this embarrassing juncture.
 
I just looked at the brass case prep sticky here again, and you sir are 100% correct. I have been doing it wrong with my 6.5 CM brass for 4 firings now...:mad: Well, thanks for not pushing my face in the mud at this embarrassing juncture.

With 4x firings on brass that's been sized that much I would section a case and look for thinning around the web before loading again, just to be safe.