Powder coat questions

fiver said:
cause the trailing edge ain't all jacked up.
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NOT buying it.

The "trailing edge" becomes the front end of the bevel now. When gas escapes between bullet and bore, it happens at the front edge of the bevel and STILL is subject to the same effects.

The BASE is not the problem, the last part of the bullet to exit the bore IS.

On a bevel base, all the same SH....TUFF is happening, it's just happening on a different part of the bullet at, a different time.
 
Jeff.
lead goes somewhere when it's moved by sumthin.
now if your junk ain't dead on straight going into the mush zone stuff is crooked.
it's crooked clear down to the bottom and shoved more off at one side than the other.

if that mushed stuff is hidden in a hole, rather than hanging off the back....
 
fiver said:
Jeff.
lead goes somewhere when it's moved by sumthin.
now if your junk ain't dead on straight going into the mush zone stuff is crooked.
it's crooked clear down to the bottom and shoved more off at one side than the other.

if that mushed stuff is hidden in a hole, rather than hanging off the back....
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I get that, fiver, BUT...

It does not change the fact that the front edge of a bevel becomes the point at which the gas escapes between the bore and bullet.

A bevel-base bullet does NOT alleviate the "fins" having an effect on the escaping gasses at the base, it just changes where/when the "base" is on the bullet.

Gas is not going to wait until the base passes, it's going to escape the second it CAN, which is when the front edge of a bevel base leaves the muzzle.

There is STILL going to be displaced metal at the point where the bullet is no longer touching the bore.
 
My new MP mold, 135gr SWC has the BB. So far it's been very easy to get shooting in everything I've got. The Lyman 358091 shoots good and easy to find loads for also. That little 135gr MP HP NLG is one of my trials in life. It doesn't shoot well with my RMR/Range lead amalgamation but does ok with straight RMR lead. It's my 1st NLG mold and I've only purchased 2 other NLG molds since with about the same issues. I wish I'd had a clue about buying BB molds when I bought those. a383ea0b-fed3-4a39-bbf2-a69285464443.jpg
 
Jeff.
you got a 35 cal lever rifle?

i think i might still have a mold i could cast some bullets from and send to you for a little test.
 
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Jeff H said:
I get that, fiver, BUT...

It does not change the fact that the front edge of a bevel becomes the point at which the gas escapes between the bore and bullet.

A bevel-base bullet does NOT alleviate the "fins" having an effect on the escaping gasses at the base, it just changes where/when the "base" is on the bullet.

Gas is not going to wait until the base passes, it's going to escape the second it CAN, which is when the front edge of a bevel base leaves the muzzle.

There is STILL going to be displaced metal at the point where the bullet is no longer touching the bore.
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You're forgetting thay lead displaces differently coming off of a 45⁰ base angle or angled bottom driving band than from a 90⁰ trailing edge.

A flat base bullet will cup on the bottom with a star-shaped set of radial ridges that can run all the way to the center. The trailing edge of the engraves can actually curl. These are weak areas that might blow off, or not, or just some of them at muzzle exit and cause tipping.

A bevel based bullet will simply extrude the cone slightly after being engraved. There won't be sharp 'tails' on the ends of the engraves, either, just little crescent-moon bulges.

Ultimately what makes the difference is the STRENGTH of the trailing edge surface which exits the crown, and plain/flat based bullets have the lowest strength in that area off all three base designs we're discussing here.
 
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I'm stealing my thread back. Powders showed up today with UPS. Saved one of those big Costco sour cream tubs from the garbage and next time I'm at the shop I'll set up and attempt to bake some bullets.
 
Ian said:
You're forgetting thay lead displaces differently coming off of a 45⁰ base angle or angled bottom driving band than from a 90⁰ trailing edge.

A flat base bullet will cup on the bottom with a star-shaped set of radial ridges that can run all the way to the center. The trailing edge of the engraves can actually curl. These are weak areas that might blow off, or not, or just some of them at muzzle exit and cause tipping.

A bevel based bullet will simply extrude the cone slightly after being engraved. There won't be sharp 'tails' on the ends of the engraves, either, just little crescent-moon bulges.

Ultimately what makes the difference is the STRENGTH of the trailing edge surface which exits the crown, and plain/flat based bullets have the lowest strength in that area off all three base designs we're discussing here.
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OK, that makes sense. I can't say I've witnessed it, because I haven't looked too hard at recovered bullets and only shoot one which has a bevel base. I also can't say that the fins on a flat base have ever caused me any grief, but I shoot plain-base so slow and not too far, so I'm not putting them to much of a test.

fiver said:
Jeff.
you got a 35 cal lever rifle?

i think i might still have a mold i could cast some bullets from and send to you for a little test.
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I do, Fiver. I've not talked much about it, because I'm not pleased with it and I know I complain enough as it is. Don't want to wear everyone out with grousing about that too. This is a new Ruger-Marlin 357 Mag "Trapper." Nicest-made new Ruger I think I've pulled out of a box but heavy and bulky for what I need.

Which mould? Maybe I have it.

Are YOU looking to learn something or looking to teach ME something with the test? I'm game either way, but I'm having a hard time getting any shooting done, so it might be a while.
 
Shoot a bunch of all three designs in different calibers and speeds and you'll see a pretty obvious trend. I have VERY few plain-based bullet moulds anymore, most are either bevel base or gas check designs.
 
I do believe a BB will shoot more accurately than a FB but culling the BB is tough. I solved the problem by removing most of the GC shank on a rifle mold. Had to use a hard alloy but pushed 30cal 14 gr PB to 2100 fps and accurate. HV gas leaves the muzzle at a high angle for FB, any 'error' in base is magnified. The 'sharp' edge is the weak point. Angle is lower - more aligned with bore for BB and tougher base. If you stand them during PC cook, coating may be thicker toward the base but doesn't add to toughness of the base.
 
well.
it's something so obviously wrong you'd think there ain't no way.
but then it does,,, up to a point.
however there is a lesson.

i can guarantee even if you have the mold,,, you ain't got this version of the mold.
i'll have to dig through the drawers to see if i still have it.
it's one of my geeze what was i thinking to learn when i started doing that to a brand new 50$ [1980's 50$] mold.
 
Ok my head hurts so a BB will allow the smushed lead a place to go and is a flatter surface than a FB that gets smushed lead tendrils on the edge?
So a BB potentially has a better ability to go straighter?
 
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yes and no. I think a lot has to do with the type of crown you have. Look at how the crown is chamfered. Every maker does it different and different angles and depth of the chamfer. And I think the deeper the chamfer the more it could effect the gas getting around the base tilting the bullet as it exits.
 
Got all my stuff today. Using the prismatic blue mentioned earlier in the thread, black BBs and a sour cream container. This is after 3 minutes of shaking. Doesn’t look right to me….

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Maybe add a bit more powder. One thing that helps me is to put the basket of bullets on top of your oven and get a little heat into the bullets. Not too much. Just up past room temp.
 
Use a larger container and fewer bullets. They are rubbing the powder off. Possibly too many BBS. I couldn't get the coolwhip thing to work, got some bigger WM tubs that work fine. Swirl, don't SHAKE! Shaking just distributes the powder, doesn't add any STATIC.
 
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There have been crown studies from 90 to 45 degrees and it makes absolutely no difference whatsoever to j-bullet accuracy.
 
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