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headbangerJD
February 28, 2010, 11:25 PM
What are the pros and cons of these 2 bullet shapes? Does one offer better performance than the other?
I ask this because fmj 9mm and 45acp bullets are rounded, but fmj 40sw bullets always have flat tips, and i'm not sure why they're different.

Thanks,

Jd

railroader
March 1, 2010, 12:30 AM
I think the reason the 40 cal bullets are flat tipped is to fit in the mag. The 40 cal round was designed to fit in a 9mm size gun. Being the 40 case is longer than a 9mm case and both rounds need to fit in the same size mag a flat point bullet makes sense for 40 cal ammo. Mark

headbangerJD
March 1, 2010, 10:31 AM
That makes sense, but does the flat-nose have any effect on performance?

Walt Sherrill
March 1, 2010, 10:45 AM
No.

You're talking hardball (non-expanding) ammo, in either case -- and performance for them is whether they go where aimed.

(Hollow-point ammo is not round nosed, either.)

nefprotector
March 1, 2010, 10:50 AM
I think of it like this. Round Nose pierce through the target. The Flat nose punch their way through the target like a Hammer. Just my thoughts.

BlueTrain
March 1, 2010, 12:51 PM
There is at least one brand of .45 ACP available with a truncated cone profile (flat point). The difference in performance on either living or inanimate targets may or may not be significant but those few handgun bullets designed with ultimate penetration in mind have literally sharp pointed bullets.

rodwhaincamo
March 1, 2010, 01:18 PM
The flat nosed bullets will make a neat clean hole in paper.
I understand they also do better when a penetrating bullet is needed for hunting. The round nosed bullets may be deflected by bone from what I hear.

podrav
March 1, 2010, 01:32 PM
round nose
- better balistics, but not important at handgun ranges
- better penetration

flat nose (also called 'wad cutter')
- great target round since they make a clean hole in paper
- maybe a bit more wounding and reduced penetration (poor man's HP)

Webleymkv
March 1, 2010, 03:34 PM
Flat-nosed bullets are generally preferred as they cut cleaner holes in targets, have less tendency to ricochet, and wound better than round-nosed bullets. Both 9mm and .45 ACP do have factory loadings available with flat-nosed bullets. The reason that so many 9mm and .45 loadings still have round-nosed bullets is that these two cartridges are much older than .40 S&W and there are many older guns that will not function reliably with flat-nosed bullets.

Bud Helms
March 1, 2010, 04:38 PM
All flat-nosed bullets are not wadcutters. Both have a flat nose.

Norrick
March 1, 2010, 05:23 PM
flat nose probably lose velocity faster, but in a handgun, this is sort of a moot point anyway.

Accuracy should not be affected, as long as the bullet is symmetric about the central axis and has the rotation imparted on it by the barrel rifling.

There was a show I watched on TV where a guy was trying to recreate the myth of shooting a man down from a noose, and he switched from regular bullets to semi-wad-cutters and had better results.

My guess would be the flat edge provides a greater shear against some objects, whereas parabolic bullets sort of "squeeze" their way through targets.

SQUAREKNOT
March 1, 2010, 10:07 PM
Think a knife wound versus a hammer. The flat point "meplat" bullet does more damage. both can kill but the flat points have the shock power.

jrothWA
March 1, 2010, 11:22 PM
you're talking about "bearing area".
The RN will concentrate it energy on a point contact, the FP has a wide contact THAT should increase energy transfer.

Israel developed the FP, back in late 70' / early 80's, USDOD use early ammo for the 9mm acceptance test then had to redo as NATO spec didnot allow for the FP, as it may hangup on feed ramps.

Have use the Hornady 124gr FP for bowling pin shoots and they APPEAR to make the pins MOVE, when a solid hit, some RN don't seem the same.

Have last lot of the Hornady .45 230gr FP's, that I loaad up when hiking/ backpacking in the Cascades. I had talked with their tech and it was indicated that ammo should be good for black bear, if needed.

Only real good way to know, would be using a "ballistic pendulum" and see the results.

North Bender
March 2, 2010, 07:03 AM
Elmer Keith swore by the knock-down power of flat point bullets.

That guy was an animal mass murderer - he shot everything that walked, slithered or flew. Those were the old days. His "Keith" style bullet is still a gold standard in 45 Colt. Aside from the lube rings and weight, the flat point was essential to him.

1goodshot
March 2, 2010, 07:26 AM
40 cal bullets are like that so the over all lenght is the same as the 9mm.