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View Full Version : Heavyweight 9mm JHPs. Poor choice for compacts?


Dannicus
10-01-2011, 1:57 PM
looking at various online sites it looks lt looks like 9mms at 147gr are doing over 900fps out of short barrels (3-3.5") Shoudn't that be plenty fast for expansion?

PRonyan
10-01-2011, 2:15 PM
Pow'r ball 100 grain will get almost 1,200 fps out of the same barrel

Dannicus
10-01-2011, 2:18 PM
Pow'r ball 100 grain will get almost 1,200 fps out of the same barrel

Yeah, but that's not the point.

paul0660
10-01-2011, 2:35 PM
Pow'r ball 100 grain will get almost 1,200 fps out of the same barrel

I would hope so.

den888
10-01-2011, 8:02 PM
One thing about the heavier bullet weights is that recoil is noticeably heavier. You would definitely feel the difference between, say, a 115gr jhp and a 147 jhp.

M. D. Van Norman
10-01-2011, 8:11 PM
That depends on the powder load.

InGrAM
10-01-2011, 8:14 PM
You should be fine.
I use Golden Saber 147 gr JHP in my P-11. They have less felt recoil than with my Federal 115 gr FMJ rounds and lighter defensive bullets.

bussda
10-01-2011, 9:12 PM
looking at various online sites it looks lt looks like 9mms at 147gr are doing over 900fps out of short barrels (3-3.5") Shoudn't that be plenty fast for expansion?

Let me put on my flame suit...

There is a big controversy about expansion and muzzle velocity. If you look at the expansion tests, they are usually done with 4.5 and 5 inch barrels. That is then applied to shorter barrels and the same results are expected. Expansion does not reliably occur, however. And there are exceptions.

Choose your round. See how the muzzle velocity for your choice corresponds between test data and your weapon. For example, I want 1200 fps for a 124gr. hollow point. I do not know the minimum speed for a 147gr. hollow point, but think about 1000 fps may be good.

Californio
10-02-2011, 10:05 AM
I like the Speer Gold Dot Short Barrel Load. It groups very tightly with a magazine dump, which is important to me, out of a 3" barrel.

http://www.midwayusa.com/viewproduct/?productnumber=216634

I am more concerned about multiple rounds hitting in the same area than what one round will do.

Gryff
10-02-2011, 3:56 PM
looking at various online sites it looks lt looks like 9mms at 147gr are doing over 900fps out of short barrels (3-3.5") Shoudn't that be plenty fast for expansion?

I thought 1,000fps was considered the general minimum speed for reliable expansion?

Dannicus
10-02-2011, 6:30 PM
I thought 1,000fps was considered the general minimum speed for reliable expansion?

Can you provide a reference?

Lone_Gunman
10-02-2011, 6:46 PM
I like the Speer Gold Dot Short Barrel Load. It groups very tightly with a magazine dump, which is important to me, out of a 3" barrel.

http://www.midwayusa.com/viewproduct/?productnumber=216634

I am more concerned about multiple rounds hitting in the same area than what one round will do.

Just fired some of this through my LC9 last night. Plenty accurate and the lack of muzzle flash was very noticeable.

DRAB_81
10-02-2011, 6:53 PM
I thought 1,000fps was considered the general minimum speed for reliable expansion?

It all depends on each manufacturer's bullet design. A 147gr Gold Dot is more likely to expand at a lower velocity than a 147gr XTP, due to cavity size and jacket construction.

From what I've read, the 147gr JHP's don't vary much in velocity whether it's a 3" or 5" barrel. The lighter 9mm bullets, especially +P, seem to have a more drastic drop in velocity with a short barrel. The Kahr PM9 camp seems to favor the 147gr JHP's for this reason.

G60
10-02-2011, 7:11 PM
When it comes to ballistics questions, i'd look someplace where people actually know what they're talking about.

check m4carbine.net terminal ballistics forum, pistol-training.com forum, specifically posts by DocGKR.

Tier One Arms
10-02-2011, 7:14 PM
Your best bet is to go with a 124 gr +p round such as the Speer Gold Dot

DRAB_81
10-02-2011, 7:53 PM
Your best bet is to go with a 124 gr +p round such as the Speer Gold Dot

Why?

zfields
10-02-2011, 7:54 PM
Why?

Higher velocity out of a shorter barrel.

Dannicus
10-02-2011, 8:50 PM
Your best bet is to go with a 124 gr +p round such as the Speer Gold Dot

It's the safe "bet". It's a middle weight round, pushed with +P pressure. Unless it has exceptionally disruptive recoil, which it might.

Dannicus
10-02-2011, 8:56 PM
It all depends on each manufacturer's bullet design. A 147gr Gold Dot is more likely to expand at a lower velocity than a 147gr XTP, due to cavity size and jacket construction.

From what I've read, the 147gr JHP's don't vary much in velocity whether it's a 3" or 5" barrel. The lighter 9mm bullets, especially +P, seem to have a more drastic drop in velocity with a short barrel. The Kahr PM9 camp seems to favor the 147gr JHP's for this reason.

Looking at the tables from here:
http://www.ballisticsbytheinch.com/9mmluger.html,

The lightweights do vary by more fps, but they're screaming fast anyways. What's a couple hundred fps when you're in the neighborhood of 1300?

2nd Shot
10-03-2011, 8:40 AM
It may seem strange, but I believe heavier bullets retain more of their long barrel velocity in a shorter barrel, than light bullets of the same caliber. I've definitely found this true when I was shooting 10mm loads over a friends chrono, and I believe 9mm is no exception.

I use 147 grain HST's - they test very well in scientific tests, have a huge cavity up front, and long pre formed cuts through the jacket and core going into the cavity to get the petals started.

DRAB_81
10-03-2011, 11:33 AM
Higher velocity out of a shorter barrel.

That's true, but higher velocity does not always mean better expansion/penetration. In 10mm for example, a 180gr JHP @ 1300fps will smoke a 135gr JHP @ 1700fps when it comes to internal ballistics.



The lightweights do vary by more fps, but they're screaming fast anyways. What's a couple hundred fps when you're in the neighborhood of 1300?

What 9mm ammo are you using that gets 1300fps after losing a couple hundred fps?

A couple hundred feet per second can be a HUGE deal. Each bullet is designed to expand within a certain velocity window. If that velocity is not achieved because of the short barrel, you might as well be shooting FMJ's.

I chrono tested RA9124TP (Ranger 124gr +P) out of my G26 a while back. Winchester advertises 1180fps (4" test barrel), and I had a 10 shot average of 1181fps of my G26's 3.46" barrel. It proved to be fine as far as velocity goes, but take another 1/2" off the barrel length and it may change things. Next time I get a chance, I'll chrono some RA9124TP out of my PM9. Here's a link to my chrono thread: http://www.calguns.net/calgunforum/showthread.php?t=342134
.
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Dannicus
10-03-2011, 6:43 PM
i was just referring to the data on Bullets by the Inch. Off the top of my head the 90gr 9mms were hitting around 1500 fps.

DRAB_81
10-03-2011, 9:07 PM
i was just referring to the data on Bullets by the Inch. Off the top of my head the 90gr 9mms were hitting around 1500 fps.

That makes sense. I just assumed you were referring to a 124gr round, mainly because nobody really recommends anything lighter than that.

Another interesting thing that ballistics by the inch showed, is the velocity difference between the 3" Para & the 2.9" Rohrbaugh. I wouldn't have guessed that 1/10" would eat up 100fps. I guess it just goes to show that velocity can also drastically vary from gun to gun, even with basically the same length barrel.

VulpesVafrae
10-03-2011, 9:54 PM
disregarding bullet expansion. What about accuracy? 9mm is right in between super and sub sonic, (transonic?) or goes from first to second. I heard that trajectory can be affected when an object transfers those speeds. Would it be more accurate to keep a load below super sonic? IE, heavier grain at lighter charge?

Not that I have an issue making 1000 yard + shots with my 9mm :rolleyes: , I was just more curious on the physics stand point.

PRCABR4Christ
10-03-2011, 9:58 PM
You should be fine.
I use Golden Saber 147 gr JHP in my P-11. They have less felt recoil than with my Federal 115 gr FMJ rounds and lighter defensive bullets.

I run 147gr in my P-11, it doesn't like 115gr :facepalm: