Ballistics Question

[SJG 253]

What do you think is a high-velocity  9mm target round that can be fired from a 9mm AR style rifle?

[Scorpio64 5,153]

If you are looking for a high BC 9mm round for a carbine, I don't think they exist.  Otherwise, +P+ ammo is pretty hot.  A carbine chamber will probably handle the extra pressure but you should confirm with the barrel/gun maker.

[GRIZ 3,369]

The 9mm round with the best ballistic coefficient is probably a tapered point fmj.  The extra velocity from a +P or a +P+ really doesn't give you a lot when it comes to velocity or better ballistics in a 16 inch barrel.

There is also many types of 9mm parabellum ammo that will slow down in a carbine barrel compared to a handgun.  Subsonic rounds often do.

What are you trying to do?  I shoot mostly 9mm NATO in my 9mm carbine.  Just about every 9mm ammo I've shot groups 3-5" at 100 yards. That's about 2.5" high at 50, zeroed for 100, and drops 5"  at about 125.  As you can see that's far from flat shooting.

[PK90 3,570]

[Scorpio64 5,153]

1 minute ago, PK90 said:

Seems like a 14.5" bbl with a comp would be ideal.  Was looking at some 9mm Luger bullets, interesting, there are heavy for caliber boat tail bullets available.  9mm carbine could be a lot of fun for experimenting with load development but as a practical matter it defeats the purpose of being able to share ammo between carbine and pistol.  A slightly slower burning powder would keep those pills accelerating all the way out.

[GRIZ 3,369]

A boat tail bullet really doesn't have much benefit until the range gets past a few hundred yards.  It has less benefit with a 9mm bullet that has a low bc compared to rifle rounds to begin with.

I've seen results of guys experimenting with slow burning powders in 9mm carbines.  Yes they did increase velocities.  Not enough to make any big difference AFAIC.  It seems like a lot of experimenting just to prove it can be done.  Not to produce a very useful benefit.  If it's because you like to experiment that's another story.

You can easily surpass any improvement you make with a 9mm carbine by getting a 357 Magnum carbine.  Lever action only but gives you a significant increase in performance with a 35 caliber bullet.

[SJG 253]

Chart helps. Thanks

[Scorpio64 5,153]

8 hours ago, GRIZ said:

You can easily surpass any improvement you make with a 9mm carbine by getting a 357 Magnum carbine.  Lever action only but gives you a significant increase in performance with a 35 caliber bullet.

Honestly, pistol caliber carbines are crap for anything over 100 yards, and 100 is really pushing it.  I loved the Tommy gun but my dad, a WW2 vet, told me they were shit for anything other than city fighting.  Most of the deer hunters I know that hunt with 357 or 44 mag usually wont take a shot past 75 yards. Pistol caliber carbs are great for a very specific role, but, like a golf club, you have to use the right caliber for the job. 

I was kinda surprised to see a boat tail bullet for a pistol caliber.  But, like I said, it could be interesting to mess around with.  With hand loads, half the fun is load development.  Pushing a bullet to it's max performance.

[GRIZ 3,369]

1 hour ago, SJG said:

Chart helps. Thanks

Go to ballistics by the inch.

1 hour ago, Scorpio64 said:

Honestly, pistol caliber carbines are crap for anything over 100 yards, and 100 is really pushing it.  I loved the Tommy gun but my dad, a WW2 vet, told me they were shit for anything other than city fighting.  Most of the deer hunters I know that hunt with 357 or 44 mag usually wont take a shot past 75 yards. Pistol caliber carbs are great for a very specific role, but, like a golf club, you have to use the right caliber for the job. 

I was kinda surprised to see a boat tail bullet for a pistol caliber.  But, like I said, it could be interesting to mess around with.  With hand loads, half the fun is load development.  Pushing a bullet to it's max performance.

A 45 230 fmj only gets to about 1000 fps in a carbine barrel.  Maybe about the same in a sub gun.

You might get a 124gr  9mm to 1500 fps.  A 357 can get a 158 gr to 1700 fps in a factory load.  A 357 125 gr carbine can easily hit 2000 fps.  I have some factory 125 gr 357s that do over 1700 fps in a 6 1/2" Blackhawk.  I haven't chronoed them but I'm sure they would do 2000+ in a carbine.

One of the issues in loading an expanding pistol bullet to super velocities is the the bullet will expand and fragment early.  I've seen gel results where the 357 carbine penetrated less than the same load in a handgun.

I agree 50-75 yards is about max range for 357 or 44 magnum on deer.That's got more to do with the ability to place those rounds than the energy.  Those pistol caliber carbines aren't far behind a 30-30 that's taken a gazillion deer.  If you make an entry and exit wound all that extra pent ration doesn't do anything for you.

Reloading for maximum performance takes two forms.  Accuracy and power.  Usually your more accurate loads are far off from the highest velocity loads.  I've been reloading about 45 years and side for accuracy over velocity.  I've never been much for rhino roller loads.  If I need more than a 357 I'll use a 44, more than a 44 and I'll use a 308 or 30-06.

If your thing is seeing how hot a load you can make up without blowing up your gun  that's fine.  It's not mine.

You're never going to improve a 9mm parabellum much by handloading.

[Parker 213]

Hornady's 147 gr. bullet has a B.C. of .212. That's slightly better than a softball. 

[GRIZ 3,369]

4 hours ago, Parker said:

Hornady's 147 gr. bullet has a B.C. of .212. That's slightly better than a softball. 

Correct. And for the record that's not a boat tail.  It's a taper to allow easier starting in the case.

[High Exposure 5,664]

I don't understand this thread....

What's the intended use here? What do you want this "high velocity" 9mm to do?