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SHMACKITY2K
01-17-2013, 11:25 PM
Buying two mold cavities very soon. One .45 ACP and one 9mm. Both six cavitiy molds. The .45 ACP will be a 230 grain and the 9mm will be 124 grain bullet. My only dilemma is deciding between truncated cone or round nose. Can someone please explain the advantages and disadantages betweeen the two.

Bigslug
01-17-2013, 11:42 PM
There is also a kind of middle ground - the round-nose, flat-point. . .but to answer your question:

A round nose has the advantage in feeding reliably in multiple styles of firearm. The downside is that it is "streamlined" when passing through meat, blood, bone, etc. . . and tends to push tissue out of the way, making a clean hole.

A truncated cone has a flat point that will tend to crush and tear tissue at its leading end.

The round-nose, flat-point combines the desirable qualities of both. It's basically the profile of the round nose with the point cut off. The bits of the boolit that contact the feed ramp and 12:00 portion of the chamber have the same contour, so feeding is unchanged, but you get the sizable flat nose that can still deliver a decent terminal effect.

I just started casting with an Accurate Molds 45-230-F that fits this last category. You might want to give it a ponder. Their 35-125-B appears to be the 9mm equivalent. Both should run quite happily in a wide variety of pistols.

runfiverun
01-18-2013, 01:44 AM
i can't tell you much either, i also rnfp's in both guns.
the 45 was designed with a rn and the 9 was designed with the t/c.

MtGun44
01-18-2013, 01:47 AM
The H&G 68 SWC or clone is a super reliable feeder in .45 ACP. I use the Lee 356 120TC in
9mm with excellent results. IMO, the 'advantage' of RN for feeding is overrated.

Bill

Artful
01-18-2013, 03:48 AM
Depends what you want it for, Competition and best feeding and don't care about results in flesh - RN. For real world use against things that run or bite - I want a FN.

I still remember when I took a 38 spl loaded with 358311 RN 158 and shot my first game - unless you nailed the spine or head they just ran off - granted they probably died but not where I could ever find them.

fredj338
01-18-2013, 05:04 PM
As noted, RN are nearly 100% reliable feeding. They do punch small holes, even in paper. So if you are paper punching & your gun feeds them, I prefer TCFP.

SHMACKITY2K
01-18-2013, 05:07 PM
Thanks for the input everyone. I will take it all into consideration.

fecmech
01-18-2013, 09:31 PM
In the 9MM I have used the LEE and RCBS TC bullets with excellent results. In the .45 used the Lee TL TC with the same results. No feed problems (agree with MTgun44 on rn feed overrated) and great accuracy. Neither a RN or small meplat TC would be my choice for SD.

Cherokee
01-18-2013, 09:37 PM
I use the TC design in both 45 and 9mm. Completely reliable. 9mm TC is more accurate in my guns than the RN I also have/tried. SWC can work good on both cartridges.

DennisMcharold
01-20-2013, 04:33 PM
I use the TC design in both 45 and 9mm. Completely reliable. 9mm TC is more accurate in my guns than the RN I also have/tried. SWC can work good on both cartridges.

Had the same experience.

Multigunner
01-20-2013, 04:48 PM
The Browning style auto pistols were designed with round nose bullets in mind, and generally will feed either style with no problems. If the flat point of a Truncated Cone bullet catches on anything while feeding, its almost certainly due to some defect in the magazine or the charge.

The 9mm Luger cartridge used a truncated cone bullet till 1916, and was only switched to a round nose due to the Hague Convention concerns over excessive suffering, not due to feed problems.
The round nose 9mm ammo actually had more feeding problems in a Luger with worn magazine catch cut outs.
American cartridge manufacturers continued to use the truncated cone bullet into the 1930's.

The SuperVel ammo I used with my P-35 used a truncated cone hollow point, the profile being chosen for most reliable feed in the widest variety of 9mm handguns.