pb bullet bases

[black44hawk]

Hats off to this forum. I am always impressed with the wealth of knowledge. Anyway, I just recently purchased the Lee 158 RF for my 357 and (mea culpa) did not realize that it has a beveled base. It just seems so counter-intuitive: how does a beveled base seal off the chamber? How do BB bullets obdurate? And finally, why don't I just save my money and buy a Keith mold?

[fecmech]

I've used the bullet in my .357 rifle, pistol and .38 spl pistol and it works fine. Accuracy is good out of all of them and leading is not a problem. I bought it to try in the rifle but discovered that my 9MM 150 2R is the best for that gun. If I had it in a 6 cav I would use it more, I just can't make them fast enough with the 2 cavity.

[Buckshot]

..............A good BB slug will shoot alongside a flatbased slug, given the same care in loading, etc. Apparently the issue is that it's harder to get a perfect BB then it is a perfect plain or flat base.

I have a couple articles, one being from "Handloader" mag I beleive, but both reports were fairly extensive in trying to prove the accuracy potential of one design over the other. The author had a couple revolvers of known accuracy shot from a Ransom Rest. The moulds were from H&G's and of the same design with the exception of one being a BB and the other a PB.

He could prove no statistical difference. He sent an unidentified lot of each to Speer for a further test in their ballistics lab.

They also found no difference in accuracy potential.

...................Buckshot

[454PB]

I only own one BB design mould, but it seems like a solution to non-existing problem. Mine is the Lee 230 gr. .45 TC, and they shoot fine, but are a PITA to size and lube, leaving a ring of lube at the bevel base.

[Bullshop]

Question, will a BB cut drag (raise BC) on a long range BPCR boolit?
For some odd reason Lyman has made thier 43/44 cal rifle boolits with a slight BB. I have two, one an Ideal and one a Lyman and both are BB.
I have a Victory mold for a long Postell style boolit but was cut for a GC. I want to have the check shank milled off but what would become the base band is a BB. I am not sure weather I should go past the BB or leave it. If it would raise the BC then maybe it would be better to leave it. Thoughts please.
BIC/BS

[DonH]

This is just an opinion because I haven't tried it to verify but I think if the bullet is cast from a typical BPCR alloy (20-1, 25-1, 30-1) and fired with black powder that post-obturtion there won't be much bevel left on the bullet base. A significant amount of bevel like a boattail form would be different of course. Only one way to see if it will work. Or one coould go to the MSN BPCR forum and post the question for Dan Theodore who is on th ecutting edge of bullet design for that type of rifle.

[DonH]

BTW, the bevel base on the H&G #68 I shoot from my .45 ACP match gun has never seemed to hurt accuracy one bit. It does save aggravation in bullet seating when loading in quantity as well as damaged bullet bases.

[44man]

Funny this just came up. I just tested this yesterday. I have the Lee 358-158-RF mold. I could not get it to group so I cut the BB out of the mold.
The first target is the best I could do with the BB. The second is the flat base. I worked loads and accuracy was best with the same load for both boolits.
I was shooting Creedmore and the low shot on the right target was called low because the barrel slid down my blast shield getting the front sight too low and the gun went off before I could correct it. I had been shooting my cap and ball from it and I never washed the grease off. Ever shoot off a greasy shield?
Remember, these were shot at 50 yd's.

[arkypete]

I only own one BB design mould, but it seems like a solution to non-existing problem. Mine is the Lee 230 gr. .45 TC, and they shoot fine, but are a PITA to size and lube, leaving a ring of lube at the bevel base.


A question:
I have a Redding 135-140 grain SWC 357 bullet that has a bevel base that has proved to be accurate. Like you I will get a lube ring around the bevel base. Normally I will use a towel to wipe off excess lube then seat the bullet.
I've gotten lazy on occasion and didn't wipe off the lube. There was no diference.
Aside from being messy and maybe having powder stick to the base of the bullet, what is the down side of lube on the base of the bullet?
Jim

[SharpsShooter]

A question:
I have a Redding 135-140 grain SWC 357 bullet that has a bevel base that has proved to be accurate. Like you I will get a lube ring around the bevel base. Normally I will use a towel to wipe off excess lube then seat the bullet.
I've gotten lazy on occasion and didn't wipe off the lube. There was no diference.
Aside from being messy and maybe having powder stick to the base of the bullet, what is the down side of lube on the base of the bullet?
Jim

The downside is the potential for powder contamination resulting a squib load and a bullet stick in the bore. Some lubes claim to have no effect, but if you have a clump of powder imbedded in the excess lube, it will not ignite correctly.



SS

[Sundogg1911]

I always hated bb boolits when I was using a Lyman 450 sizer. I got tired of wiping the lube off each one of the bases. I never saw a need for a BB when loading with my Dillons. Now that I have Star sizers I don't have the lube issue so I have quite a few bb moulds for my Master Caster that I picked up used. They seem to shoot fine, but I would still prefer plain base when givin the choice.

[leftiye]

If your pressures are high enough with a bevel base or a cast boattail boolit to deform the base (obturate, or overpower the strength of your alloy) of your boolits, then your accuracy will go South (or just away). Plain bases will also possibly deform in this situation, but as they are supported by the chamber/ barrel they will not deform as much nor as readily.

I don't like plain bases, but you can see why I like bevel bases even less. The bevel base acts like the nose of a boolit loaded upside down would, and just crushes- with nothing controlling what shape it will take. Therefore, forget a square line at the outside of the base happening.

[44man]

I like the way you explained it. My thoughts exactly. I consider the bevel base an abortion. Someone figured it out for mass production speed loading. If it hits the hole in the brass, it goes in.

[Cherokee]

I have a 6cv Lee 358158 FN bullet. Cast easy, sized great in the Star. Shoots little groups at 25 yd from my S&W 686 with HS6 and cleans the deck at the pin shoot. Works for me. OTOH, I have some BB bullets that I size in the 450 or 4500 and if I keep the lube pressure at a reasonable level, I don't have the lube ring on the base. I use Thompson Red hard lube and a heater.