Design Differences

[rodwha]

What is the functional differences between a typical SWC, truncated cone, RNFP, and Keith style FN bullet?

When I look at them I see very little difference in meplat sizes, but it seems everyone has their favorites.

[RickinTN]

I've cast, loaded, and fired some of each. I know sometimes in a semi-auto one style will feed better than another. I'm curious to see what the others who have more experiences than I do have to say.
Good question,
Rick

[btroj]

It often isn't the meplat that matters.

I like bullets that smoothly taper from nose to body diameter with no leading band. I think they center in the bore better.

The flat nose does the work on impact but the shape of the nose matters for accuracy, feeding, and how much weight is outside the case.

[RickinTN]

"I like bullets that smoothly taper from nose to body diameter with no leading band. I think they center in the bore better."

I agree with you fully and am currently learning this in 30 cal bullets in my '06's and 308's. They all have a fairly gentle leade.

Rick

[tazman]

The meplat size really only matters when you are trying to kill what you are shooting at. There are lots of boolit designs that people think are better than another because of some small detail in the form.
As long as it feeds in my pistol reliably and hits what I aim at, the size of the meplat means nothing to me. I am just as satisfied with a round nose if it meets my first 2 criteria.

[rodwha]

I mostly hunt, and like a wide FN design. This is in revolvers so feeding isn't an issue.

I'm considering having a few cavities hollow pointed, which reminds me of the old "flying ashtray" bullets for the .45 ACP.

btroj: By smoothly taper do you mean as in a TC/SWC?

[btroj]

http://i1348.photobucket.com/albums/p733/Btroj/image_zpsf1334105.jpg (http://s1348.photobucket.com/user/Btroj/media/image_zpsf1334105.jpg.html)

I mean like this. A TC is an entirely different beast.

[Grump]

typical SWC,
Like the H&G 200-gr SWC
102235

Note the sharp shoulder where the transition is from the bore-hugging cylinder portion to the nose cone. Give you nice clean holes in all targets, though printing your own on high-quality copy paper can lead to some tearing on one side. Longer cellulose fibers in that stuff. Targets are typically printed on short-fiber papers.

truncated cone,
102237

Note no shoulder. Technically, TC profiles are really geometrically a truncated cone atop a cylinder.


RNFP,
102248

again, no shoulder, but you see the nose profile is not straight like a regular SWC or a TC, it's rounded. Used to be very common with the black powder cartridges--nice because they would not light up the primer of the round in front, in a tubular Winchester-type underbarrel magazine.

Think of it as a truncated round nose...

and

Keith style FN
102238
This one is more like I remember them being, before commercial casters in the 1980s popped up like daisies in the springtime and were getting their automated moulds from who knows where.

Note the variations on this photo of three, all of which are probably called "Keith" SWCs.
102240

Back to having a shoulder. I think some go too far towards the wide meplat thing, making them too close to being just super-long full wadcutters (cylindrical, often with a small "button" raised up on the nose, like 1/16-inch high and almost to the edge).

I will leave it to the purists to define what is REALLY a Keith SWC.

[leeggen]

I want to thank all of you, the idenity of the 4 types are very simular and I was never realy sure how to Id them. When together it is easy to see. Thanks again from another wondering mind.
CD

[rodwha]

Indeed a typical SWC has that shoulder mentioned, though some don't. It all seems like a similar idea, and I'm not sure how a Keith style bullet differs much from a typical SWC design, though the meplat seems a bit wider as some of the SWC's have.

What does a wider meplat Keith type SWC have over a WFN?

Myself, enjoying hunting, like a wide FN design as I want the largest wound channel I can achieve, and from a revolver, the overall design doesn't play a significant role.

I am a bit curious, though, how a non expanding WFN differs from a broad head. It seems a broad head creates an ever greater wound, though plugs it with the arrow shaft.

btroj: I tend to gravitate to that sort of design myself.

[RobS]

I'm in the camp of a smoother transition profile and put together LFN style designs. I've shot truncated, swc, round nose, Keiths, WFN & then LFN styles with both a secant and tangent nose profiles. I also don't like a front drive band that has a shoulder and my preference especially for revolvers are to design a LFN style boolit with a tangent nose profile and a meplat around 74-75%. I do have a combo design for lighter 45 Colt and heavier 45 auto with a weight of 235 grains but runs with a bit smaller meplat to feed well in the auto.

[deerspy]

RobS what mold is it that has 235 grain that would work for 45 colt, I am wanting to start to load for 45 colt du you have pic of bullet
Thanks

[RobS]

RobS what mold is it that has 235 grain that would work for 45 colt, I am wanting to start to load for 45 colt du you have pic of bullet
Thanks

Here you go:
http://www.accuratemolds.com/bullet_detail.php?bullet=45-235R-D.png

If you are going after only a revolver boolit in that weight I also put this one up:
http://www.accuratemolds.com/bullet_detail.php?bullet=45-230X-D.png

A little heavier, this one is really a nice one too however I didn't design it but have a very similar mold:
http://www.accuratemolds.com/bullet_detail.php?bullet=45-250E-D.png

[deerspy]

thanks RobS

[GaryN]

My GP100 really like the 359640 Mihec boolit that looks exactly like Brad's drawing. But then my Super Blackhawk really likes the 429421. I just try them all and see what the gun likes.