9mm Bullet base differences

[mrcabinet]

For years I've seen both flat base and conical case pistol caliber bullets. I was thinking about it today and realized that I've always purchased the flat base - not on purpose but just because. I have an opportunity to pick up some 9mm jacketed round nose for a very good price, but they are conical base. Is there anything I should consider, reloading wise, before I take the plunge on them? Is the only difference a tad more room under the bullet? is there a performance difference between the two?

Your experienced replies are greatly appreciated.

[painter]

I like conical based bullets because they load easier on a single stage press without any belling on the case.

[SI VIS PACEM PARRABELLUM]

^^^This and they are plenty accurate as well. You have to work up your "pet" load with any bullet so there's no special consideration for conicals that's any different than anything else.

[DWARREN]

X-Treme has some conical based plated bullets that I have used and worked very well. Extra heavy plating and you can run them hard.

[Wobbly]

Please don't make us guess.

Supply a photo or provide a link to what you're talking about.

With 9mm pistol bullets you always have to consider the shape of the ogive in the CZ. Or are you talking about boat tailed rifle bullets ??

[mrcabinet]

I don't have any photos (yet). A guy at work has them and he said he'd bring them in sometime this week. I've never used a conical base before so I appreciate the info from those that have. Boattail in a 9mm? Now that would be interesting!

[1SOW]

I haven't seen "conical based" 9mm bullets, but I have shot thousands of "Hollow Base" 124 gr 9mm bullets.
The only issue when reloading is to realize that the bullet length doesn't give the "functional seating depth".
The recessed/hollow base ADDS space inside the case,  so the pressure build up will be slightly less than a flat base bullet at the same seating depth.

With the BRY 124 HBRN bullet,  the airspace added due to the bullet base recess is equivalent to more than 6 or 7 thousandths less seating depth.  Not a biggy.

Hope this makes sense.

[snakeye]

X-Treme has some conical based plated bullets that I have used and worked very well. Extra heavy plating and you can run them hard.

Really! Extreme has conical base bullets...I have never seen those there...I have seen and used their heavy plated concave base (HPCB) bullets before

[jameslovesjammie]

I haven't seen "conical based" 9mm bullets...

Me either.  Are we talking about bevel base bullets?

[mrcabinet]

Conical, bevel, hollow, cone - are these just different terms for essentially the same thing?

[painter]

Conical, bevel, hollow, cone - are these just different terms for essentially the same thing?

No.

A bevel based bullet, and a hollow base are different. For instance, the Berry's HBRN-TP is both a hollow base and beveled.

Do you have pictures of the bullet?

[jameslovesjammie]

Conical, bevel, hollow, cone - are these just different terms for essentially the same thing?

Bevel Base




Hollow Base




Base Guard, Cup Base, Dish Base, Flat Base

[mrcabinet]

Thanks for the photos James. I had no idea there were that many variations in bases, And no photos yet - he hasn't brought them in.

[SlvrDragon50]

Had no clue that many bases existed...

[IDescribe]

I've never heard anyone use the term conical base prior to this thread.  I'm sure he means bevel base.  Some bevels are more generous than others.  The bevels I see on XTReme plated bullets are so modest that I'm not quite sure whether or not to consider it a bevel base at all. I just examined a 200gr swaged semi-wadcutter from Zero, and it's advertised flat base, and even that has an ever-so-slight bevel.  If there were truly no bevel at all, it would be a sharp edge that would certainly deform when seating anyway.

The performance difference between flat base and bevel base is that flat base tend to be more accurate when shooting pistols over long (for pistols) distance.  If I see conversations where people are extolling the values of flat base bullet accuracy, they're talking about 50 yard bullseye shooting where they care about fractions of an inche at 50 yards.  No one shooting regular target practice or practical shooting events should worry about whether or not they're shooting flat base or bevel base. 

I can't imagine it makes a measurable difference out to 35 yards, and as we all know, it's between 35 and 50 where things fall apart.